Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: SCTusk on May 08, 2010, 01:06:47 AM
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No criticism intended here, just a hope for improvement; had a look at the aircraft stats for the WW1 tour just ended:
WW1 Tour 2 Statistics for all planes/vehicles/boats
Plane Name Kills Deaths Kill/Death Ratio
D.VII 10397 11066 0.94
Dr.I 16877 12533 1.35
F.1 4943 7181 0.69
F.2B 2297 3734 0.61
Totals 34514 34514 1.00
The Kill/Death ratio tells the story... as it stands the DR1 is almost twice as effective as the Camel. I don't think this can possibly be accurate, and when you consider the Camels' Vickers have twice the firing rate of the DR1s' Spandaus (yep, it's modelled as per the real deal - I bet that answers a few questions lol) well, that just screams 'problem with flight model'. Here's a few extracts from Wikipedia (possibly not the most accurate reference but it'll do for now).
On the Camel:
"In the hands of an experienced pilot, its manoeuvrability was unmatched by any contemporary type. Its controls were light and sensitive. The Camel turned rather slowly to the left, which resulted in a nose up attitude due to the torque of the rotary engine. But the engine torque also resulted in the ability to turn to the right in half the time of other fighters,[3] although that resulted in more of a tendency towards a nose down attitude from the turn. Because of the faster turning capability to the right, to change heading 90° to the left, many pilots preferred to do it by turning 270° to the right.
Approximately 5,490 units were ultimately produced. The Camel was credited with shooting down 1,294 enemy aircraft, more than any other Allied fighter in the First World War."
And the DR1:
"Compared to the Albatros and Pfalz fighters, the Dr.I offered exceptional maneuverability. Though the ailerons were not very effective, the rudder and elevator controls were light and powerful. Rapid turns, especially to the right, were facilitated by the triplane's marked directional instability. The triplane had to be given up because although it was very maneuverable, it was no longer fast enough. Postwar research revealed that poor workmanship was not the only cause of the triplane's structural failures. In 1929, National Advisory Committee for Aeronautics (NACA) investigations found that the upper wing carried a higher lift coefficient than the lower wing — at high speeds it could be 2.55 times as much. The triplane's chronic structural problems destroyed any prospect of large-scale orders. Production eventually ended in May 1918, by which time only 320 had been manufactured. The Dr.I was withdrawn from frontline service as the Fokker D.VII entered widespread service in June and July.
Frontline inventory peaked in late April 1918, with 171 aircraft in service on the Western Front."
So, my 2 cents worth; if the DR1 was half the fighting machine we see in the WW1 arena they would have made them by the thousand. What we have at the moment is a slick little grass height uber flat turner which can balloon up and get a firing solution on anything that comes in high. And there's no significant speed difference either, not enough to extend safely. As a Camel driver I have two options, kill quickly on or after the merge (and the HO is apparently unchivalrous, while hard flat-turning and then shooting you in the back is ok) or chuck a few evasives until help arrives or the battle damage brings you down.
I'm not asking for much, just a bit more of that legendary torque induced right turn capability to force the Tripe pilots to fly instead of drive (that's DRIVE with an R) when I do the honorable thing and allow them to sail past on the merge unscathed.
(hunkered down and standing by for incoming fire... as usual)
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The Dr 1 has the same type of torquey rotary engine as the Camel, so that's not the issue.
Mechanical failures, IE: The triplane's chronic structural problems...
, are not modeled in AH2, so that's not an issue either.
What it comes down to in game, I believe, is visibility. You can see out better in the Dr 1 than in the Camel, especially forward/up.
You can't shoot what you can't see to maneuver behind.
wrongway
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See Rule #4
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Thanks for chipping in wrongway but I think you'll find the standard DR1 powerplant was 110hp while the standard Camel rotary was 130hp. The reputation as the quickest right turner is, I believe, accurate. Also, you pointed out:
What it comes down to in game, I believe, is visibility. You can see out better in the Dr 1 than in the Camel, especially forward/up.
You can't shoot what you can't see to maneuver behind.
I genuinely don't have that much of a problem with visibility in the Camel, and neither apparently did the pilots in WW1 ("The Camel was credited with shooting down 1,294 enemy aircraft, more than any other Allied fighter in the First World War." - Wikipedia)
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Wrongway.
"THAT'S PAINT!"
Out.
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The Kill/Death ratio tells the story... as it stands the DR1 is almost twice as effective as the Camel. I don't think this can possibly be accurate, and when you consider the Camels' Vickers have twice the firing rate of the DR1s' Spandaus (yep, it's modelled as per the real deal - I bet that answers a few questions lol) well, that just screams 'problem with flight model'.
You are making a very flawed assumption.
In some mid-war scenarios the Hurri2C retains a much higher K/D against more advanced and versatile planes like the Fw190A-5 or the Bf109F-4. Does this mean the Hurri2C is overmodelled as well?
The Aces High in-game K/D has absolutely nothing to do with the FM.
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Does this mean the Hurri2C is overmodelled as well?
Sounds like you think so.
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In answer to your post Kweassa, I haven't flown AH WW2 for about a year, so I don't want to project any of my assumptions into those arenas. Perhaps the Hurricane 2C is flown by only a few top guns, maybe the K/D ratio it enjoys mirrors that achieved in WW2, or perhaps it's over modelled. It's even possible that modelled correctly it still over performs due to the differences between the game and the real world, and the way the game is played as opposed to the way pilots might behave in real situations, in which instance there might be a case for modifying it. I don't know what the problem is there. You would have to address that issue seperately.
In the WW1 arena the majority of players seem to be flying the DR1, which rules out the 'top gun' aspect, I think we're seeing a reasonably accurate 'average' result there. Interestingly the Camel drivers (the ones who stick at it - a very small minority) tend to be persistent and committed, which would suggest at least competent. So unless the Tripe was twice as effective in WW1 as the Camel, it's a fair bet that one if not both of these aircraft has been modelled incorrectly. And when I give the Camel a crack with the whip, she drops her port wing a few inches and carries on ponderously through the turn with complete disregard for gyroscopic effects (i.e. precession). I'm not sure if those are even modelled in AH, if not I presume some simple workaround could be attempted, it's the outcome we're after not necessarily the pure science.
If something isn't done, we're virtually flying in the face of history in there. The sky is full of DR1's (wrong) and the Camels have a terrible combat record (wrong). Add that to the constant rushing around in circles cutting the grass and we're not far off becoming the arcade game laughing stock that other sim afficionados seem to think we are :( That would be a shame because it has so much potential.
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No offence SCTusk, but it's somewhat hard to take you seriously when you obviously quote the best possible things you can find on the Camel and worst possible things you can find on the Dr.I. All selective quoting like that proves is your obvious bias. Also a flight model/aircraft model can't really be based on subjective quotes like that. Hard data is needed. And lastly the effects of the gyroscopic forces acting on the Camel are also acting on the Dr.I. The engine weights are similar and when it comes to the virtues and vices of the effects that rotary engines causes to the flight characteristics, Camel doesn't really have anything special that other rotary engined fighters don't have and vice versa.
The gyroscopic effects are very much modelled in AH. There's quite the difference between Camel/Dr.I and D.VII/F2B. Actually, I haven't flown a sim where they are as beliveable modelled as they are in Aces High. If you can't notice those effects then the fault really isn't in the sim...
The WWI arena hardly is an exact representation of WWI aerial warfare. The low altitude furballing setup and excessively long shooting distances greatly favor more maneuverable fighters.
Having said all that...
Yes I do think there might be one thing that causes some of the discrepencies. Dr.I speed is commonly listed as 115mph at sea level but it most probably is overly optimistic for the production plane with 110hp Oberusel. If Dr.I would be 5-10mph slower I think that could change things quite a bit.
Here's some speed data for the Fokker Dr.I collected and calculated by KACEY from aerodrome.com forums:
(http://i273.photobucket.com/albums/jj213/kcib2u/aeroplane%20stuff/FokkerDrI.jpg)
Very interesting thread on the speed of Dr.I here: http://www.theaerodrome.com/forum/aircraft/34238-fokker-dr-i-maximum-speed-6.html (http://www.theaerodrome.com/forum/aircraft/34238-fokker-dr-i-maximum-speed-6.html)
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hard to take you seriously when you obviously quote the best possible things you can find on the Camel and worst possible things you can find on the Dr.I.
All selective quoting like that proves is your obvious bias
Wmaker, please provide alternative quotes with references in which DR1 shot down 1,294 Allied aircraft, was manufactured in large numbers, was generally considered to be the quickest turning aircraft, and where the Camel was so poorly designed as to limit its' production to just 320.
Yes I am biased, based on the information. If I'm misinformed then post your evidence.
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Wmaker, please provide alternative quotes with references in which DR1 shot down 1,294 Allied aircraft, was manufactured in large numbers, was generally considered to be the quickest turning aircraft, and where the Camel was so poorly designed as to limit its' production to just 320.
Yes I am biased, based on the information. If I'm misinformed then post your evidence.
<sigh> Ok, my point whizzed about 3 feet above your head.
Plane's service record in the real war is irrelevant when it comes to Aces High's WWI arena. When Mosquito won't stand up to it's loss per sortie record of the WWII in the LWMa arenas, are you gonna claim there's something wrong in the modelling then aswell?
You think something is wrong with the modelling and you post vague subjective quotes that really don't bring any backing to your claims. With one table I brought more factual data on this thread than you have yet posted to support your claim.
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<sigh> Ok, my point whizzed about 3 feet above your head.
Wmaker, I find your presumption of my inferior intellect very informative.
you post vague subjective quotes that really don't bring any backing to your claims
Numbers manufactured, numbers of nme a/c shot down, numbers in service.... subjective?
With one table I brought more factual data on this thread than you have yet posted to support your claim.
That was a table? Sorry I thought you'd posted a screenshot of some of your kills. I was going to ask if the green one was me.
Surely we'd all like to see the WW1 arena improve, and most people I've asked seem to want more historical accuracy. I'm not entirely sure why you're on my six here.
What is it they say these days?.... chill bro :cool:
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Numbers manufactured, numbers of nme a/c shot down, numbers in service.... subjective?
Depending how you use them: Yes.
Numbers of aircraft built or number of kills are no "hard data" in regards to FM. The combat environment in AH is totally different from a real world one, both for WWI and WWII.
Just because a plane XY got Z kills in real live doesn't prove that it's over- or undermodeled. WMakers Mossy argument is quite a good one - in "real life" it was far more "successful" in terms of K/D as in AH.
You can't simply say: It's got soandso many kills in RL, so torque in Ah is wrong.
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Wmaker, I find your presumption of my inferior intellect very informative.
That wasn't my intent at all!
Sorry! My apologies.
That remark just stemmed a bit from frustration. I didn't mean to imply anything to do with intellect...I just think that you aren't looking to this issue from the same angle as I am and therefore didn't understand my point. That is what I meant.
Numbers manufactured, numbers of nme a/c shot down, numbers in service.... subjective?
Well, those numbers are irrelevant when it comes to actual, raw, physical performance of an aircraft, yes.
That was a table? Sorry I thought you'd posted a screenshot of some of your kills. I was going to ask if the green one was me.
I assume you having some kind of joke on me which I don't quite get but...can you see the Dr.I speed chart I posted?
Surely we'd all like to see the WW1 arena improve, and most people I've asked seem to want more historical accuracy. I'm not entirely sure why you're on my six here.
Totally agreed. The ease of long range shooting is something I'd like to see getting a looksee. I did a bit of testing and noticed that the dispersion of the WWI mgs at any given range is about the same as the dispersion of the 109 7.9mm cowl mgs.
Camel right now in the game has its gyroscopic effects modelled and as far as I can tell, turns clearly better to the right than it does to the left. I don't really see any problem there.
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Well whatever the reason the problem is too many players flying the DR1 simply because you typically can't survive in a Camel once the DR1's start their flat turns. They just creep around behind and game over. Breaking out of the turn generally kills you even quicker, I realise that the obvious tactic is not to get sucked into it in the first place but the Camel should be up for it, and then some, at least in a right hand turn.
I guess we could search for performance data for both a/c with reference to turn rates, whether such data exists (or even ever did exist) I don't know. It certainly would make interesting reading. In the absence of data I can only go with a lifetime of anecdotal evidence which suggests that the Camel was unbeatable in the right turn, due largely to the "placement of the engine, pilot, guns and fuel tank within the front seven feet of the aircraft, coupled with the strong gyroscopic effect of the rotary engine." (Wikipedia)
Whatever the reason, the fact remains that the WW1 arena is dominated by the Dr1. I guess the introduction of more a/c could make this a moot point, but I have no idea when or even if that will happen.
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I flew the Camel almost exclusively for the first week or two of WWI.
I think a big part of the problem with it's k/d is that you can't get the nose stabalized to take a shot. By that I mean that, with the Camel, there's a noticable dead area in the center of my stick and any attempt to correct my aim causes an over-reaction in the planes nose once I finally get it to move. This, in turn, never allows me to align a shot and spray and pray is the best I can hope for. None of the other WWI or WWII aircraft display this tendency, at least not to the extreem degree the Camel does. The Dr1 by comparison has a very stable nose and is a solid gun platform, even though it's also a radial.
For that reason, I gave up on the Camel and, in large part on WWI. I really wanted to fly and like the Camel but that dead area in the stick was just too frustrating.
Other than that I think it flys as described by most accounts, both on it's own merit and in comparison to the other AC modeled. It's quite cabable in any type of engagement and it does display a strong preference for right vs. left turns.
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You might want to actually fly WW1 before you make a fool of yourself.
Exactly what are you speaking of?
Both A/C have rotary engines so torque effects are similar. So, as I said before, it's not the torque in this case as opposed to the Dr 7 which doesn't suffer from the turning mass of a rotary engine.
As I also stated, you can move your head enough to pretty much see around the top wing on the Dr 1 where in the Camel you can easily lose sight of the enemy once they cannot bee seen through the "hole" in the upper wing.
Anything I've gotten incorrect?
Just based on my, albeit, limited flying in the WW1 arenas.
wrongway
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Sorry to hear about the deadzone problem BaldEagl, I'm wondering if that might be an issue with your stick or something as I don't have any problems with the Camel as a gun platform.
On the turning question, you said:
it does display a strong preference for right vs. left turns.
Again I don't see that; not even on time trials. Possibly I'm abit ham fisted and don't notice, but if there is a difference, is it significant enough to justify this:
Because of the faster turning capability to the right, to change heading 90° to the left, many pilots preferred to do it by turning 270° to the right.
(Wikipedia)
If that anecdote can be believed, there must have been a huge advantage to turning right rather than left. I'm just not seeing it in the FM.
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Dr.I's and Camel's wingloadings are very close to each other but Dr.I's wings have higher lift coefficients. Therefore, is hardly suprising that Dr.I has a smaller turn radius than the Camel.
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Oh..."torque." I misread the thread subject. Guess the wife's right that I *do* have a dirty mind. :devil
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Dr.I's wings have higher lift coefficients. Therefore, is hardly suprising that Dr.I has a smaller turn radius than the Camel.
I'm sorry Wmaker but aerodynamics is a complex business, lift coefficient (even with reference to wing loading) alone doesn't prove anything. Even what appears as a simple question like 'which a/c turns better?' requires further definition. We'd need to consider whether we're asking about turn radius, rate of turn, immediate or sustained, etc so it's no wonder these issues are often clouded by misunderstanding. Usually the best turn rate is achieved well above stall speed, while the smallest turn radius requires a speed just above the stall.
I'm suggesting that the legendary turn rate of the Camel when turning right due to gyroscopic effects (not sustained, just immediate) be properly modelled if possible. If not, then your own suggestion of reduced speed in the Dr1 would probably be a good workaround.
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AWwrgwy said, and I quote
"Exactly what are you speaking of?
"Both A/C have rotary engines so torque effects are similar. So, as I said before, it's not the torque in this case as opposed to the Dr 7 which doesn't suffer from the turning mass of a rotary engine."
How is the Camel supposed to have a huge advantage in a instantaneous turn to the right over the Dr1 when then both have similar motors with similar torque?
Compared to the DVII both the Camel and the Dr1 do have a very tight initial right turn.
But there is no huge advantage to the camel compared to the DR1.
That brings it back to what everyone else said.
Basically that a few mph slower for the DR1 is offset by its excellent views. After all at even 5mph it takes a long long time to go from 300 yards to over 800 yards and get out of effective shooting range.
It might be that if we could get the fights to start up around 8 - 10k that you would see a different outcome.
I suspect you'd see a lot more Dr1's with ripped wings until they learned how to fly it up there.
But you really can't complain about the modeling when you really have not proven that there is anything wrong with it.
Your just not seeing the big super advantage that you thought you'd see.
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I'm sorry Wmaker but aerodynamics is a complex business, lift coefficient (even with reference to wing loading) alone doesn't prove anything. .... We'd need to consider whether we're asking about turn radius, rate of turn, immediate or sustained, etc so it's no wonder these issues are often clouded by misunderstanding. Usually the best turn rate is achieved well above stall speed, while the smallest turn radius requires a speed just above the stall.
<sigh> What exactly did I say? Which was I talking about, rate or radius? I think I distinctly said, smaller radius because that's what more lift per weight will give you. Aerodynamics indeed is complex business, I suggest you take even a small clance into that direction.
Again, they both have similar weighing rotary engines turning into the same direction. Just because few books happen to specially mention Camel doesn't mean that it has some magical properties the other rotary engined fighters of the era didn't have.
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Aerodynamics indeed is complex business, I suggest you take even a small clance into that direction.
Wmaker I took your advice and had a small glance at one of my old photo albums. Several old black and white photos of a couple of aircraft I designed and built (and one of which I test flew) back in the early 80's. I was also inspired by your comments to revisit some of the books in my aviation library concerning aerodynamics. I thank you for that. I also thank you for the benefit of your clearly superior knowledge on the subject.
I'd like to add, that in respect to the Camel, the literature (including pilot anecdotes) suggests an unusual ability to turn to the right rapidly (I cannot find reference to whether this was sustained or initial, but I suspect initial) due to the placement of most of the mass in the first seven feet of the fuselage combined with gyroscopic effects; that the peculiarity of the design, which concentrated the centre of mass close to the centre of gravity caused an instability which made the aircraft difficult, even dangerous to fly yet gave it remarkable manoeuvrability. Such a potent ability that turning left 90 degrees was often performed by turning right 270 degrees. There is a similar amount of literature on the Dr1, none of which mentions such an ability, or the accompanying vices, but does mention a predisposition to regular tight turns and generally pleasing handling characteristics (i.e the Dr1 does not appear to have had the unusual instability required to produce the aforementioned ability).
I don't know any Camel or Dr1 pilots; I only have what little information there is in a 'few books' as you say, and my own experience in aviation which goes back well over 40 years. There is obviously some opposition to my suggestion, fair enough it's just a 'wish', posted I believe in the correct forum. I have no problem with that. Neither do I have a problem with anyone who chooses to presume that they know the truth of the matter (I think I've made it clear that I'm referencing historical material here and am open to new evidence). The thing I have a problem with (apparently) is communicating the main points of my argument, unless what I've seen here is deliberate obstinacy, in which case (as I'm sure you're aware) nothing I say will make any difference.
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Wmaker I took your advice and had a small glance at one of my old photo albums. Several old black and white photos of a couple of aircraft I designed and built (and one of which I test flew) back in the early 80's. I was also inspired by your comments to revisit some of the books in my aviation library concerning aerodynamics. I thank you for that. I also thank you for the benefit of your clearly superior knowledge on the subject.
Considering this backround of yours, I'm truly baffled of the angle you chose to approach this issue. :headscratch: Considering your backround, I would think you would have first tested both aircraft in the game to determine their turning radius to both directions. Then found out the liftcoefficients, wingloadings and put them through the lift equation just to see if the things are in the right ballpark...instead of saying: "Because so and so many Camels were produced and they shot down this and this many enemies it must turn better to the right in the game and better than Dr.I does."
As I said, I truly am baffled. :confused:
I also thank you for the benefit of your clearly superior knowledge on the subject.
My knowledge or the lack of is actually pretty much irrelevant here. Just reply to what I post and when I'll do the same, our backrounds are irrelevant.
...that the peculiarity of the design, which concentrated the centre of mass close to the centre of gravity caused an instability which made the aircraft difficult, even dangerous to fly yet gave it remarkable manoeuvrability. Such a potent ability that turning left 90 degrees was often performed by turning right 270 degrees.
I don't quite see how this kind of layout helps aircraft to have faster turn rate or radius in a sustained turn. Except small benefit of keeping the moments arms between center of lift and center of gravity as small as possible (almost non existant?). The stability helps the aircraft to respond quicker to control input and therefore helps to intiate the starts of the maneuvers quicker (ie. instantanius turn rate) but again, I don't see how it helps once the turn enters into the sustainable region. I think you are drawing wrong conclusions from these anecdotes. This type of instability definately adds to the 'percieved' maneuverability through keeping the controls light and very responsive but it basically does nothing to make the sustained turning radius smaller for example.
I don't know any Camel or Dr1 pilots; I only have what little information there is in a 'few books' as you say, and my own experience in aviation which goes back well over 40 years.
None of this alone really helps to determine weather something is modelled wrong or not.
There is obviously some opposition to my suggestion, fair enough it's just a 'wish', posted I believe in the correct forum. I have no problem with that. Neither do I have a problem with anyone who chooses to presume that they know the truth of the matter (I think I've made it clear that I'm referencing historical material here and am open to new evidence). The thing I have a problem with (apparently) is communicating the main points of my argument, unless what I've seen here is deliberate obstinacy, in which case (as I'm sure you're aware) nothing I say will make any difference.
The opposition comes from the fact that flight models aren't changed with the whim of an opinion. Your wish makes about as much sense as me asking Bf109 to do everything better than all other Aces High fighters because it scored the most kills in WWII out of all fighters that took part to the war.
Also, nowhere have I said I know "the truth" of the matter. I just said that considering the variables involved the percieved turning radiuses of both of these fighters seem very believeable in game. If you think something is wrong it's your job to do in game testing and point out any discrepencies you can find against hard data. HTC doesn't pull these flight models out of thin air.
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The stability helps the aircraft to respond quicker to control input and therefore helps to intiate the starts of the maneuvers quicker
Here I course meant to say instability, not stability. Sorry.
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I think I read the AH Camel has the most common engine fitted to the aircraft, the 130hp Le Clerget. However a lot of Camels had 150hp Bentley BR-1 engines instead. I believe almost all the RNAS' aircraft were so equipped. In the interests of balance wouldn't an easy fix for the Camel's lack of competitiveness in the MA be another 20hp?
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I think I read the AH Camel has the most common engine fitted to the aircraft, the 130hp Le Clerget. However a lot of Camels had 150hp Bentley BR-1 engines instead. I believe almost all the RNAS' aircraft were so equipped. In the interests of balance wouldn't an easy fix for the Camel's lack of competitiveness in the MA be another 20hp?
I too believe that Camel is currently powered with its most common engine, the 130hp Le Clerget 9B. Personally, I always would like to see every plane in its most common configuration when it comes to things like powerplant and armament. I've understood that the Bentley engined planes were "relatively" rare...I mean compared to the 130hp engined ones.
I still think that another look to the top speed of the Dr.I and the dispersion of the WWI mgs in general might go a long way of at least relieving the issue a bit.
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In the absence of 'hard data' on the real Camel with regard to this phenomenon the issue moves away from a numbers game and becomes one of judgement. I'm sure HiTech and his team are far more capable and experienced at in game research, development and testing than I am. Hopefully they might take a quick look at the problem (Dr1 dominance), the possible cause (lack of or insufficient gyro effects in Camel) and decide (based on the anecdotal evidence) to tweak the FM a little, not so much perhaps as to induce Camel drivers to turn right 270 degrees instead of turning left 90 degrees; I think too much realism would deter even more players from flying it. But just enough to give it a bit more of a fighting chance.
I don't quite see how this kind of layout helps aircraft to have faster turn rate or radius in a sustained turn. Except small benefit of keeping the moments arms between center of lift and center of gravity as small as possible (almost non existant?). The (in)stability helps the aircraft to respond quicker to control input and therefore helps to intiate the starts of the maneuvers quicker (ie. instantanius turn rate) but again, I don't see how it helps once the turn enters into the sustainable region. I think you are drawing wrong conclusions from these anecdotes. This type of instability definately adds to the 'percieved' maneuverability through keeping the controls light and very responsive but it basically does nothing to make the sustained turning radius smaller for example.
Ok Wmaker if you own a gyroscope feel free to try this, if not I guess you'll just have to take my word for it. Spin the mass and hold the device arm outstretched such that the mass is turning clockwise from your perspective looking at it from 'behind' (along the axis of rotation). This corresponds to the rotation of the rotary engine in the Camel. Now move your arm stiffly right and left. You should notice some tendency for the device to pull or twist up when going left, and down when going right. This moderate effect known as precession replicates the type of reaction we see in a rotary engine aircraft configured normally, i.e. the engine is way out the front well clear of the centre of gravity, which has been moved rearward by the various other large masses being spread around to create a CG roughly one third the chord back from the leading edge of a wing (pair of wings CG position more complex especially if staggered) situated appropriately further back along the fuselage.
In the case of the Camel however, most of the mass was packed into the nose. The wings were well forward to compensate (bringing the wings to the CG as it were) so much so that the aircraft flew generally 'tail heavy'. So the mass is concentrated close around the CG. To replicate the gyroscopic effects in this situation run the experiment again but this time turn the device right and left using your wrist. You will notice a much more powerful tendency for the device to twist up when going left, and down when going right. Now hold the frame of the device from the side, such that you are looking across the axis of rotation with the left side of the mass moving toward you (i.e. replicating looking down on the Camel from above). Spin up and twist the device clockwise and anticlockwise using your wrist. Notice that the left side of the device pulls or twists down (away from you) when turning the device anti-clockwise, and up (towards you) when turning clockwise.
So the combined effect of the gyroscopic phenomenon in the Camel would have been a tendency to go outside wing high in the turn (which assists in both directions) but nose high in a left turn forcing adverse control input in pitch (stick forward) and extra input in yaw (left rudder) to hold the nose. In a right turn there would have been a requirement for extra pitch input (stick back) and adverse yaw input (left rudder) to hold the nose, but in this case the 'adverse' yaw input is actually a misnomer as it would actually result in simply less right rudder input, and you would generally be wanting the nose to stay down anyway to maintain your speed.
The overall result then is to produce somewhat clumsy turns to the left but rapid turns to the right, and on second thoughts I do believe these would have been sustainable. So long as the motor is still spinning the forces would continue to apply. I doubt very much if hard data existed back in the day (WW1 pilots would have paid scant attention to them anyway), the effect was pronounced enough to have given the Camel a reputation as a dangerous machine for the novice, and induced many of its' pilots to turn right 270 degrees rather than turning left 90 degrees fighting the stick. The Dr1 spinning a lighter mass placed further away from the CG albeit at similar rpm would likely have experienced significantly less of this effect, much like the initial experiment with the gyroscope at arms length, which would explain why the effect seems never to be mentioned in respect of the Dr1 in the available literature.
So I guess the question remains, has this been modelled accurately, or even should it be? Clearly that's not my decision to make, but I suspect that anyone who takes the time to fiddle with a gyroscope and look closely at the evidence will have some thinking to do.
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In my experience the AH Camel turns better to the right (and drops its nose in the process) and turns worse to the left (and raises its nose to the point of stalling easily). I agree with BaldEagl that the Camel is like a bobble-head in terms of gun stability. I cannot hit much of anything except in a continuous steady right hand medium g turn (i.e. the stick is not centered). If I try to line up on a target by actually moving the stick, the thing reacts slowly then overshoots. I even find it hard to hit targets that are flying straight and steady. I don't know why it does this nor do I know if it is historically accurate, but it is annoying enough that I gave up on the Camel and on WWI.
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Ok Wmaker if you own a gyroscope feel free to try this, if not I guess you'll just have to take my word for it. Spin the mass and hold the device arm outstretched such that the mass is turning clockwise from your perspective looking at it from 'behind' (along the axis of rotation). This corresponds to the rotation of the rotary engine in the Camel. Now move your arm stiffly right and left. You should notice some tendency for the device to pull or twist up when going left, and down when going right. This moderate effect known as precession replicates the type of reaction we see in a rotary engine aircraft configured normally, i.e. the engine is way out the front well clear of the centre of gravity, which has been moved rearward by the various other large masses being spread around to create a CG roughly one third the chord back from the leading edge of a wing (pair of wings CG position more complex especially if staggered) situated appropriately further back along the fuselage.
In the case of the Camel however, most of the mass was packed into the nose. The wings were well forward to compensate (bringing the wings to the CG as it were) so much so that the aircraft flew generally 'tail heavy'. So the mass is concentrated close around the CG. To replicate the gyroscopic effects in this situation run the experiment again but this time turn the device right and left using your wrist. You will notice a much more powerful tendency for the device to twist up when going left, and down when going right. Now hold the frame of the device from the side, such that you are looking across the axis of rotation with the left side of the mass moving toward you (i.e. replicating looking down on the Camel from above). Spin up and twist the device clockwise and anticlockwise using your wrist. Notice that the left side of the device pulls or twists down (away from you) when turning the device anti-clockwise, and up (towards you) when turning clockwise.
So the combined effect of the gyroscopic phenomenon in the Camel would have been a tendency to go outside wing high in the turn (which assists in both directions) but nose high in a left turn forcing adverse control input in pitch (stick forward) and extra input in yaw (left rudder) to hold the nose. In a right turn there would have been a requirement for extra pitch input (stick back) and adverse yaw input (left rudder) to hold the nose, but in this case the 'adverse' yaw input is actually a misnomer as it would actually result in simply less right rudder input, and you would generally be wanting the nose to stay down anyway to maintain your speed.
The overall result then is to produce somewhat clumsy turns to the left but rapid turns to the right, and on second thoughts I do believe these would have been sustainable. So long as the motor is still spinning the forces would continue to apply. I doubt very much if hard data existed back in the day (WW1 pilots would have paid scant attention to them anyway), the effect was pronounced enough to have given the Camel a reputation as a dangerous machine for the novice, and induced many of its' pilots to turn right 270 degrees rather than turning left 90 degrees fighting the stick. The Dr1 spinning a lighter mass placed further away from the CG albeit at similar rpm would likely have experienced significantly less of this effect, much like the initial experiment with the gyroscope at arms length, which would explain why the effect seems never to be mentioned in respect of the Dr1 in the available literature.
I'm well aware of the effects you described here and like I said, they are already clearly modelled in AH. I also agree with you that the tendency of turning better to the right is most probably largely caused by the smaller amount of control surface drag than when turning to the left due to the gyroscopic effect of the rotary engine.
Please post data on the weights of the Camel and Dr.I engines and about their location from the CoG. Btw, as far as I know, Dr.I flew tail heavy aswell.
Once more, this is how things are already modelled in AH. Camel turns easier and faster to the right than it does to the left in AH aswell. Therefore, I don't see a problem. If you think it should turn "better" to the right than a Dr.I, then you have to prove it.
When you don't have any data it actually goes like this: "You have to take HTC's word for it." They've put the parameters of these planes into their FM, tweaked some and came up with the flight models we have now. Unless you have some kind of hard reference to compare their model against...well again "You just have to take their word for it."
Here's an interesting paper on WWI fighters: home.comcast.net/~clipper-108/AIAAPaper2005-119.pdf (http://home.comcast.net/~clipper-108/AIAAPaper2005-119.pdf)
In the Results and Discussion section it says:
"The data obtained here is intended to
illustrate the development of the fighter and fighter
tactics during WWI. The presented data is not
claimed to be accurate beyond what is required for its
intended purpose."
...So you can take it for what it's worth, but to me, the findings seem logical.
Here's a turn rate table from that paper:
(http://i46.photobucket.com/albums/f147/Wmaker/turnrates.jpg)
...I'm sure you'll say it can't be anywhere near the truth because of the disclaimer above and since it doesn't fit your agenda. :)
To me, it seems logical because of the almost identical wingloadings and clearly better lift coefficients of the Dr.I.
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I'm well aware of the effects you described here and like I said, they are already clearly modelled in AH. I also agree with you that the tendency of turning better to the right is most probably largely caused by the smaller amount of control surface drag than when turning to the left due to the gyroscopic effect of the rotary engine.
At no point did I suggest that control surface drag had any significant role in this phenomena. Your statement clearly demonstrates that you are, in fact, not well aware of the effects I described.
The AIAA paper has some apparently good data and analysis based entirely on aerodynamics alone, only mentioning gyroscopic effect in passing, and only in relation to safe handling. It would appear that the author, like yourself, either chose not to examine the effect or was unaware of its' significance. I found his comments on the relative merits of the two aircraft in question revealing:
"The figures show that the Sopwith Camel and Fokker Dr.1 were fairly evenly matched. They shared similar top speeds and climb and turn rates. However, in climb and speed, the Camel had the slight edge. This may be why the Camel was successful while the Dr.1 was not."
He obviously has no idea why. And so we see the problem with trying to understand the world around us through data alone; everything is so much more complex than the data suggests. Personally I don't trust charts, graphs and stats.... they can be useful but you first need to see the bigger picture.
"Not even the Fokker triplane could follow a camel in a right-handed bank" -Capt Henry Winslow Woollett DSO, MC and Bar - 35 victories
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At no point did I suggest that control surface drag had any significant role in this phenomena. Your statement clearly demonstrates that you are, in fact, not well aware of the effects I described.
Oh, ok. :) I thought there was something of some logic hidden in here...
The overall result then is to produce somewhat clumsy turns to the left but rapid turns to the right, and on second thoughts I do believe these would have been sustainable. So long as the motor is still spinning the forces would continue to apply.
I read a bit took much into your comments and actually tought you came up with somewhat logical reasoning regaring what causes the better turning to the right. Sorry, my mistake. :)
I'm well aware of the gyroscopic effects but no, unlike you, I don't think they magically make the Camel a better turner than Dr.I through some unexplainable force.
The AIAA paper has some apparently good data and analysis based entirely on aerodynamics alone, only mentioning gyroscopic effect in passing, and only in relation to safe handling. It would appear that the author, like yourself, either chose not to examine the effect or was unaware of its' significance.
To this, I cannot really say much else than; "whatever".
Please explain the exact mechanics/physics behind your opinion. Why exactly the gyroscopic effects of the Camel make it turn better to the right?
I can't really see any other reason than the plane was generally easier to fly in a right turn than it was in a left turn and the fact that it needed less deflection of various control surfaces in a right turn made it have less drag in a right turn and therefore haveing a smaller turn radius to the right.
I could well be missing something but you certainly haven't given a beliveable explanation why Camel's gyroscopic effects would somehow be more beneficial than Dr.I's in this regard. Considering the forces involved to an aircraft in a steady state sustained turn, I really don't see how this vague "shorter/longer distance of the engine from CoG" would have any effect. Please explain the mechanics through which you think it has an effect?
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"Not even the Fokker triplane could follow a camel in a right-handed bank" -Capt Henry Winslow Woollett DSO, MC and Bar - 35 victories
You obviously value anecdotes higher than physics or hard data. You totally ignore things like, differences in pilot skill, individual airframe's condition, perception, etc etc...
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I read a bit took much into your comments and actually tought you came up with somewhat logical reasoning regaring what causes the better turning to the right. Sorry, my mistake. Smiley
I'm well aware of the gyroscopic effects but no, unlike you, I don't think they magically make the Camel a better turner than Dr.I through some unexplainable force.
The reasoning is valid. Repeatedly claiming it isn't does not change the reality of it. The gyroscopic force is not magic, its' cause is well known and well documented. If you were genuinely well aware of it this aspect of the discussion would be unnecessary.
Please explain the exact mechanics/physics behind your opinion. Why exactly the gyroscopic effects of the Camel make it turn better to the right?
I have already explained all this up to but excluding the cause of the gyroscopic phenomena itself, which is more in the domain of a physics lesson and not something I can effectively accomplish here. If you can get hold of a gyroscope (even a cheap childs toy would suffice) and follow the guide in my earlier post I'm certain that you would realise the significance of the effect 'hands on'. If you prefer a more detailed study, look here: http://www.freestudy.co.uk/dynamics/gyroscope.pdf (http://www.freestudy.co.uk/dynamics/gyroscope.pdf)
Anyone actually familiar with the science but still curious about the modelling in AH may find this interesting. Here's the results of a few quick low speed turn tests in AH WW1 offline; subjective of course, it would help if a number of players would post their own data. Tests were conducted at about 100 feet to minimise deviation in altitude, at a sustainable speed of 80 (mph or knots? gauges not marked). Stall warning buzzer sounding but not urgent. Very little nose up or nose down tendency was evident (rudder trims were centralised from default right-trim setting prior to tests. NB failure to do this could be why some players report nose high in left turns and nose low in right turns).
All results are in seconds. Five turns each way per aircraft, recorded after initial 'settling' turn.
Camel
right turn: 9 10 10 9 10
left turn: 9 10 10 10 10
Dr1
right turn: 9 9 10 10 9
left turn: 9 9 9 9 9
My sticks are set up for the Camel and I am low time on the Dr1 so this may account for my unexpected results with that aircraft. Further testing at moderate and high speeds may also prove illuminating. At this stage (with my stick setup) any gyroscopic effects modelled in the sim appear minimal.
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The reasoning is valid. Repeatedly claiming it isn't does not change the reality of it. The gyroscopic force is not magic, its' cause is well known and well documented. If you were genuinely well aware of it this aspect of the discussion would be unnecessary.
I have already explained all this up to but excluding the cause of the gyroscopic phenomena itself, which is more in the domain of a physics lesson and not something I can effectively accomplish here. If you can get hold of a gyroscope (even a cheap childs toy would suffice) and follow the guide in my earlier post I'm certain that you would realise the significance of the effect 'hands on'. If you prefer a more detailed study, look here: http://www.freestudy.co.uk/dynamics/gyroscope.pdf (http://www.freestudy.co.uk/dynamics/gyroscope.pdf)
<sigh>
You have explained how a gyroscope works, and that's nothing new. But you haven't explained how it makes the turn performance of the Camel better to the right. And specially, how it makes the Camel with poorer lift coefficient turn better than the Dr.I. The question is simple enough, why don't you answer it?
any gyroscopic effects modelled in the sim appear minimal.
I, on the other hand, find them to be quite noticeable. :)
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The funny thing here is that only now you actually start doing some actual testing and then find that the results of your testing don't support your initial perception. :)
Another question: Would you have started this thread if you had first done this testing and found out that the results don't support you initial beliefs? :)
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I'll try to approach this turning issue between Camel and Dr.I strictly from the physics point of view.
So we have two airplanes, Camel and Dr.I. Camel produces 130hp and Dr.I puts out 110ps. Assuming similar prop efficiency, Camel has more thrust at its disposal. These planes also have exactly the same top speed of 115mph at sea level in the game. This indicates that since Dr.I has less thrust it must have less parasite drag aswell. The weights in AH match to the pound the weights mentioned in several sources. And this puts their wingloadings at 6.46lbs/sqft for the Dr.I and 6.30lbs/sqft for the Camel. So the difference in wing loading is ~2.5% for the Camel. In-game testing shows that Camel stalls at 50mph at 1000ft and that Dr.I stalls at 46mph at 1000ft, both at full flying weight. That gives Clmax of 1.02 for the Camel and 1.23 for the Dr.I, a ~20,5% difference. The stall speeds were determined by cutting the engine and maintaining altitude, the speed was recorded at the moment when visual stall buffet began. There might be a small error in the stall speeds recorded but the overall findings regarding the lift coefficients are well inline with the airfoils used in these planes:
A pic depicting the Göttingen 298 used in the Dr.I. Camel's airfoild is very close to the RAF 14:
(http://www.hq.nasa.gov/office/pao/History/SP-468/p24.jpg)
The airfoil used in the Camel, third from the top:
(http://www.southsearepublic.org/files/afc/2/sopwith_airfoil.jpg)
Now, lets consider both of these airplanes in steady state, sustained turn. The forces acting on an aircraft in a turn are, gravity, centripetal force, lift, drag (both induced and parasite) and thrust. In a sustained steady state turn, airplane's speed, altitude, turn rate and radius all remain constant and the forces are in equilibrium.
(http://upload.wikimedia.org/wikipedia/commons/thumb/a/a4/Accelerated_stall.gif/350px-Accelerated_stall.gif)
So SCTusk, which one of these forces do you think is affected by the gyroscopic forces of the Camel's engine so much that it makes up for the more lift per weight of the Dr.I? I think we'll both agree at it doesn't work as antigravity device making the plane lighter. :) So does it reduce drag? In a theoretical sense I think it's clear that it doesn't, but it probably reduces the required control input of maintaining a steady turn compared to the turn to the left and therefore reduces control surface drag and generally makes it easier for the pilot to perform the turn. So does it increase lift? I think we'll agree that it doesn't. :) Does it increase thrust? Well, the engine turns the prop which in turn provides thrust but I don't think the gyroscopic effects contribute much in the way of thrust. :)
So SCTusk, please explain how these gyroscopic effects make the Camel turn better than a plane that provides more lift per weight? To which of these forces acting on an airplane during a sustained turn does this gyroscopic force contribute to and how?
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please explain how these gyroscopic effects make the Camel turn better than a plane that provides more lift per weight? To which of these forces acting on an airplane during a sustained turn does this gyroscopic force contribute to and how?
Perhaps the following extract will convince you that these forces are real and significant:
http://yfrog.com/07gyropj (http://yfrog.com/07gyropj)
And of course, as a pure force of nature which would exist even without the aircraft being in flight (it could for instance be taxying) the aerodynamic forces are not affected. This is an additional force outside of the flight envelope which applies to the mass of the aircraft as it attempts to manoeuvre. This is simple physics and I really don't want to embarrass you further on this point.
As for my data from the turn tests, yet again you misunderstand the results. The similarity in the figures achieved only serves to emphasise my theory (that gyro effects are either not modelled or are under modelled).
If anyone reading this still doubts the significance of the effects of gyroscopic precession in a rotary engined aircraft, well Salute! You're in for a treat when you 'discover' this, as a fundamental force it's always fascinating and particularly so when you realise it for the first time.
Whether or not anyone changes the modelling on the Camel, AH WW1 is a great piece of work and very enjoyable.
Wmaker I've reached saturation point with your faulty logic, inability to understand simple explanations and endless demands. I don't see a sheriff badge so I'm just going to move along now, and bid you have a nice day. But I'd like to see the expression on your face if maybe one day you ever took the controls of a sports airplane and got a handful of precession just from the prop spinning, let alone a thumping great rotary engine whizzing around behind it. I guess you can't help not knowing something but why so stubborn? It's not like I'm trying to preach a flat world or something. Good luck with it anyway, you'll figure it out eventually.... Salute.
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Perhaps the following extract will convince you that these forces are real and significant:
I never said that they aren't. You still didn't answer the question I asked. Once again Camel and Dr.I both have rotary engines turning clockwise from the pilot's pov. Differences in the distancies between the engines and the CoG aren't going to make the plane with smaller lift coefficient to turn better.
And of course, as a pure force of nature which would exist even without the aircraft being in flight (it could for instance be taxying) the aerodynamic forces are not affected. This is an additional force outside of the flight envelope which applies to the mass of the aircraft as it attempts to manoeuvre. This is simple physics and I really don't want to embarrass you further on this point.
I never claimed that it isn't an intependent force. I said that it has to contribute/interact with the forces that are involved with a turning aircraft.
As for my data from the turn tests, yet again you misunderstand the results. The similarity in the figures achieved only serves to emphasise my theory (that gyro effects are either not modelled or are under modelled).
I should have been more clear. Yes, they don't show a difference between left and right turns but they don't show that Dr.I turns better either. I still am quite sure it does in the game though. I have to do some testing of my own sometime. There are so many handling quirks evident in these planes that tell the gyroscopic effects are very much present. How can you not see them?
From HTC 2.18 version's release notes:
"The Dr.I and the F.1 Camel both use rotary engines. The large spinning mass of these engines makes gyroscopic precession a large factor in how these planes fly. With the clockwise rotating engines of these planes, a pitch up movement will create a yaw to the right, a pitch down movement will create a yaw to the left, a yaw to the left will create a pitch down and a yaw to the right will create a pitch up."
One of the wilder effects is how these planes depart sideways after going over the top of a loop when the speed gets too low. That's what I try to use against them while flying a D.VII.
Wmaker I've reached saturation point with your faulty logic,
Right back at you. :)
inability to understand simple explanations and endless demands.
Regarding the simple explanations...Heh, whatever. :) You never explained what was needed to be explained. If you keep thinking I don't know how a gyroscope works, that's ok. :) Whatever. :) Endless demands....ahh well...
I don't see a sheriff badge so I'm just going to move along now, and bid you have a nice day.
Yeh, I'm no sheriff here. :) But you still won't get very far even if there's something wrong with the AH modelling if you can't bring hard data to the discussion which proves your point. Anecdotes can be interpreted in many many different ways.
But I'd like to see the expression on your face if maybe one day you ever took the controls of a sports airplane and got a handful of precession just from the prop spinning, let alone a thumping great rotary engine whizzing around behind it.
Yeh, that is one of the dreams of mine. Allthough, especially with a rotary engined plane, I'd most probably would be scared sh*tless and the expression on my face would probably show that very well. :)
I guess you can't help not knowing something but why so stubborn? It's not like I'm trying to preach a flat world or something. Good luck with it anyway, you'll figure it out eventually.... Salute.
I was asking you to prove there's something wrong with the AH's Camel and you never did. That's the first step of getting something changed. I'm well aware of the gyroscopic effects and how they work but I don't see how they overcome significant differences in lifting properties of the wings of airplanes (ie. making Camel turn better than the Dr.I, for example), especially when both planes are equipped with a similar rotary engine.
<S> SCTusk Have fun in the WWI arena!
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The reasoning is valid. Repeatedly claiming it isn't does not change the reality of it. The gyroscopic force is not magic, its' cause is well known and well documented. If you were genuinely well aware of it this aspect of the discussion would be unnecessary.
Please enlighten me, I can not think of any reason the forces of a gyro would make a plane turn better 1 way or the other. It appears to me, you do not know either because you just state it, or reference the math of gyro calculation. (to which some one like me will say welll duhhhh, that looks just like the AH code). But you have never posted anything to prove your statement. If a gyro does create a faster turn, it does in AH also, simply because how the forces are applied in AH.
But other then making it much easier to hold the turn, and possibly more drag on the rudder (very minor force), I can not think of any thing that would make the plane turn better.
So if you have any real reference describing or showing the force diagram I would love to see it.
HiTech
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Please enlighten me, I can not think of any reason the forces of a gyro would make a plane turn better 1 way or the other.
.....
But other then making it much easier to hold the turn, and possibly more drag on the rudder (very minor force), I can not think of any thing that would make the plane turn better.
Totally agreed. This is what I've been trying to say aswell all along.
So if you have any real reference describing or showing the force diagram I would love to see it.
While asking the same thing I am told that I don't know how a gyroscope works and therefore am just embarassing myself.... <sigh>
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While asking the same thing I am told that I don't know how a gyroscope works and therefore am just embarassing myself.... <sigh>
I know I am a clueless dolt, hence I am never embarrassed. :)
HiTech
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I know I am a clueless dolt, hence I am never embarrassed. :)
LOL! :D
Truth to be told, it doesn't bother me either. I make do with what I have and try not to worry about the rest. :)
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Good posts from all of you <S>.........(http://upload.wikimedia.org/wikipedia/commons/thumb/8/82/Gyroscope_precession.gif/220px-Gyroscope_precession.gif)
I have left posts on this topic before in other flight sim forums and it is a tough subject to explain.
Take off the front wheel of bicycle.....spin it fast and observe what happens when you turn it to the right
......then observe what happens when you turn it to the left. Pull it upward, pull it downward, ect.
If the wheel is spinning clockwise from your p.o.v. it will be easier to turn to the right than to the left and it has a tendency to
move upward. Now, imagine if that bicycle wheel was turning at 1200 rpm's and weighed in at 300 lbs or more as the Clerget, Le Rhone, or Oberursel engines did in WWI.
You would essentially be flying a giant gyroscope or flywheel with wings.
It may not be possible to model the rotary engine with the current flight sim engine because the
rotary engine was only used in WWI and was replaced by the more advanced radial engine after the war. Rise of Flight does not have the rotary engine modeled either.
Probably the best we can hope for as flight sim enthusiasts is to see the rotary engine planes modeled with lots of torque and the inline engine planes modeled with less torque.
Any articles you might find on WWI A/C will mention the planes with rotary engines turned to the right faster to the right than the left.........and had to use strong rudder if
they turned left.
Wikipedia Link of the Rotary Engine
http://en.wikipedia.org/wiki/Rotary_engine (http://en.wikipedia.org/wiki/Rotary_engine)
Wikipedia Link to Gyroscopic precession
http://en.wikipedia.org/wiki/Precession (http://en.wikipedia.org/wiki/Precession)
Here is a quote from Richard A. King
"Flying the Sopwith F.1 Camel" by Richard A. King, from Flight journal
"The engine is running wide open as I make a smooth left turn, holding left rudder throughout, and the nose moves swiftly along the horizon. A 30-degree bank brings me back on my original heading very quickly.
A right turn is an entirely different and somewhat disconcerting maneuver. Keeping the engine at 1,200rpm and with 120mph airspeed, I bank to the right, wind hitting hard against my left cheek. With the left side of the rudder bar almost fully deflected and my right knee jammed back almost to the seat, I am barely able to maintain a 30-degree bank to the right without the bank increasing. It is not a smooth right turn in any sense of the word. It takes a lot of concentration and a delicate touch with my feet on the rudder bar to maintain the constant angle of bank for the entire 360 degrees of the turn. In reality, it probably took less time to make the 360-degree right turn, but it was fatiguing and seemed to take forever to get back on my original heading.
Every flight I ever made in the Camel was as exhilarating as the first one because these sensations never changed. The 160hp Gnome-powered Nieuport 28 gave the same sensations, but because of its longer streamlined fuselage and small, thin wings, it was a little more comfortable, not just in the turns but in every other maneuver as well.
If the right turn seems to be getting away from you (out of control), usually because you're banking too steeply, the Camel's small rudder is simply not adequate to compensate for the gyroscopic effect. The only solution is to cut the ignition and let the engine rpm slow, which reduces the gyro effect. Then the aircraft once again becomes controllable. [You can even lose control in a left turn if at high power, because if you bank steeply the nose will rise and if you add too much back pressure you can easily stall.] A lot of young, inexperienced pilots failed to understand, especially near the ground. The results were usually fatal.
The Sopwith Camel can stall without too much effort. Its large cowl, propeller, struts, and wires and two machine guns in the slipstream created a lot of drag. When the engine isn't running full out, its speed drops off dramatically. Cutting the ignition and easing the stick past neutral and slightly back will quickly bring about a stall, with the nose falling off sharply, usually to the right.
I never looped the Camel, but anytime I made a loop in the Sopwith Pup, a strange thing would happen: at the top of the loop, when the Pup was inverted, the airspeed having dropped off considerably and with the engine still running at 1,200 rpm, the gyro effect of the rotating engine would force the aircraft to turn 90 degrees to the right. Thus, if you started a loop heading north, at the top of the loop, with the nose of the aircraft heading south, the aeroplane would turn to the east, and when you came out of the loop, you would be heading west. I don't have any idea where the 160hp Gnome Camel would end up if anyone tried the same maneuver. Though I am sure it was done, I have never read about or heard anyone mention the results of looping a Camel in combat"
<S>
Mano
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Mano it's modeled. Just fly a loop. :joystick:
I believe the article you quote refers to a larger engine than the one modeled in AH.
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Good posts from all of you <S>.........(http://upload.wikimedia.org/wikipedia/commons/thumb/8/82/Gyroscope_precession.gif/220px-Gyroscope_precession.gif)
I have left posts on this topic before in other flight sim forums and it is a tough subject to explain.
Take off the front wheel of bicycle.....spin it fast and observe what happens when you turn it to the right
......then observe what happens when you turn it to the left. Pull it upward, pull it downward, ect.
If the wheel is spinning clockwise from your p.o.v. it will be easier to turn to the right than to the left and it has a tendency to
move upward. Now, imagine if that bicycle wheel was turning at 1200 rpm's and weighed in at 300 lbs or more as the Clerget, Le Rhone, or Oberursel engines did in WWI.
You would essentially be flying a giant gyroscope or flywheel with wings.
It may not be possible to model the rotary engine with the current flight sim engine because the
rotary engine was only used in WWI and was replaced by the more advanced radial engine after the war. Rise of Flight does not have the rotary engine modeled either.
Probably the best we can hope for as flight sim enthusiasts is to see the rotary engine planes modeled with lots of torque and the inline engine planes modeled with less torque.
Any articles you might find on WWI A/C will mention the planes with rotary engines turned to the right faster to the right than the left.........and had to use strong rudder if
they turned left.
Wikipedia Link of the Rotary Engine
http://en.wikipedia.org/wiki/Rotary_engine (http://en.wikipedia.org/wiki/Rotary_engine)
Wikipedia Link to Gyroscopic precession
http://en.wikipedia.org/wiki/Precession (http://en.wikipedia.org/wiki/Precession)
Here is a quote from Richard A. King
<S>
Mano
There is nothing in your post that shows why they would turn better one way then the other, again as SCTusk you are just stating the obvious. You can take a statement like better to also mean easier when reading papers about turning. I.E. I would absolutely say they turn better to the right, but that does not mean faster.
The problem you seam to be missing is that the force created is perpendicular to your turning circle,(as you have stated) so if you are in a level turn there is force (more precisely a torque) at the prop that is either straight up or straight down, except what I have describe (drag) there is nothing either slowing or speeding up the turn with a perpendicular force. So if a plane turns better WHY?
Also I am not sure what you mean by modeling rotary engines. We do model them completely.
HiTech
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As another clueless dolt I have a question, probably poorly phrased but here it goes.
Since the displacement torque is acting on the center of mass (in the example on wikipedia referenced above) isn't that analogous to the aircraft center of gravity not the prop disk?
(http://upload.wikimedia.org/wikipedia/commons/thumb/2/2b/PrecessionOfATop.svg/300px-PrecessionOfATop.svg.png)
I was thinking that there is a component of the torque vector that would change the wing loading (slightly negative to the right / and slightly positive to the left) for a given turn.
Or am I completely crazy?
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As I said (more precisely a torque) . Torques are the same no mater where they are applied to a body.I.E. The roll torque of a 1 engine of a twin engine is the same as a single engine. Torque definition is a force couple of = force and opposite directions.
It was just easier to visualize as a force, not a torque since the plane is at an angle in the circle, the torque is between a yaw and and pitch. Hence it was easier to describe and Up force at the prop disk.
HiTech
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I just spent the afternoon offline with the Camel. I finally got it to be a smooth gun platform. But it took some experimentation. As for any bearing to the tehcnical complaint by the OP, this was only to try and use the tool HiTech has given us to get the most from it.
1. Fly with Combat Trim off.
2. Fly level until you reach max speed then manual trim everything. Place enough left rudder trim as needed to stop the significant right hand turn so you fly straight hands off. Once the left hand trim is in place the Camel becomes very controlable.
3. The seeming dead band area in front when trying to come to a guns solution is due to the engine torque. Cycle your throttle as you line up. I found a liberal application of throttle cycling countered the torque induced nose floating.
4. Left hand turns the nose has a tendency to rise up and slow you down. Use less throttle or cycle the throttle to help lessen this.
5. Right hand turns the nose snaps around and down. If you are fighting between 10k and 1k this is a fantastic maneuver because you can recover. Between 500ft and the grass, fast right hand turns will get you crashed. Though you can apply full left rudder while turning right to keep the nose up near the deck.
6. Do not begin a steep climb below max speed. You will stall and float tail down quicker than you can recover. I watch many Camels crash this way below 1k. Even with max speed do not climb for very long. Use the right rudder and engine torque to snap your nose down to the right. On the deck pulling up and snapping back down to the right works very well against the Dr1. They often collide with you trying to avoid your quick change of direction.
Seems you need to be willing to cycle the throttle to overcome the engine torque while maneuvering to the left or during the last moments of fine control while shooting. Otherwise when you apply left rudder your nose will track high across the target and when you correct back to the right your nose will track low under the target courtesy of Mr. torque.
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Hello hitech and Salute. Mike Goulian good enough for you?
http://books.google.com.au/books?id=PEXGjHc4858C&pg=PA21&lpg=PA21&dq=gyroscopic+precession+aviation&source=bl&ots=cfC8pu0RSM&sig=gafnjxHY_Pmvi5YGCH1llijwIoQ&hl=en&ei=bGrqS7mmGs6TkAWIkdGACw&sa=X&oi=book_result&ct=result&resnum=9&ved=0CDYQ6AEwCDge#v=onepage&q&f=false
(http://books.google.com.au/books?id=PEXGjHc4858C&pg=PA21&lpg=PA21&dq=gyroscopic+precession+aviation&source=bl&ots=cfC8pu0RSM&sig=gafnjxHY_Pmvi5YGCH1llijwIoQ&hl=en&ei=bGrqS7mmGs6TkAWIkdGACw&sa=X&oi=book_result&ct=result&resnum=9&ved=0CDYQ6AEwCDge#v=onepage&q&f=false)
Spinning prop mass probably isn't enough for these guys to detect a sustained assisting force in a right hand turn, but it should be clear that if the aircraft is moving in an arc there must be continuous precession; e.g. the right hand turn requires a continuous pitch up and yaw to the right. Since some of the right yaw is provided by gyroscopic effect (in the case of a Camel apparently all, right turns required left rudder) the pilot need only keep the stick back and the aircraft will fly more easily to the right than it will to the left. It follows that if he increases the rate of turn, the gyroscopic effect will increase the rate of turn even further. Thus a higher rate of turn is possible.
As for the supporting formula, there are plenty of sites with them on the net and elsewhere (pretty sure I already provided a link to one).
As I've already said I think AH is a great piece of work.
"If we were only able to encourage the enemy to get in a dogfight, things were easy, as a Camel could out maneuver anything." Australian ace Edgar McCloughry
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SCTusk wrote:
It follows that if he increases the rate of turn, the gyroscopic effect will increase the rate of turn even further. Thus a higher rate of turn is possible.
Again you just state it with no diagram, proof or reference reference, basically you are talking BS, The gyro creates an UP (world relative torque) when left hand flat turn down (world realative) when turning right, no where is there any thing that increases the turn.
Now as I write this it suddenly hits me, it has become completely obvious that it can NOT help you turn . The reason is very very simple Gyros do not create a force they create a torque. Torque rotates the plane but does not move it's direction of travel, this requires a FORCE/not torque. Since there is not a force only a torque created, and the force that makes you turn is lift, it is hence impossible for the gyro to increase a turn.
Saying a gyro helps a turn is the same thought that the elevator makes you turn, not lift from the wings.
HiTech
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disregard
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It follows that if he increases the rate of turn, the gyroscopic effect will increase the rate of turn even further. Thus a higher rate of turn is possible.
Once again, the wings provide the lift that aircraft needs to turn. Aircraft normally, like the Camel, have enough elevator authority to stall the airctaft in a sustained turn. If that can be done, there's not much that will make the aircraft turn faster/with a smaller radius unless the force in question somehow provides more lift or thrust. This torque caused by the gyroscopic precession does neither.
"If we were only able to encourage the enemy to get in a dogfight, things were easy, as a Camel could out maneuver anything." Australian ace Edgar McCloughry
You can post these type of quotes by the hundreds and they won't change a thing. That's the perception of a single person. As I already mentioned when you posted a similar anecdote the first time; An anecdote like this does nothing to scientifically quantify things and ignores countless amount of variables.
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Again you just state it with no diagram, proof or reference reference, basically you are talking BS
So HiTech, all those satellites whizzing around over our heads being steered by gyros are actually not working at all? I'd better get straight onto NASA lol. Have a little think here; if you could get the rotary engine working in space, found some purchase and pushed the tail around, the gyro effect would work almost exactly as already explained. It does not require air, lift, wing coefficients or a khaki paint scheme. This is a fundamental force of physics, if you shove the thing one way it goes another. The energy for the motion comes from the spinning mass. Ask someone you do respect, that would know (e.g. a professor of physics... they love being asked stuff like this).
Not sure that I'm cool with paying someone to tell me I'm talking BS. But I'll let it pass, at the moment you're clearly under the impression that I'm some sort of idiot, so no foul. I know how it is when you're confronted by what looks like a fracture in your universe. When you finally figure out the general direction of reality you can apologise, publicly :)
(actually I'd settle for slightly more gyro effect on the Camel)
You can post these type of quotes by the hundreds and they won't change a thing. That's the perception of a single person. As I already mentioned when you posted a similar anecdote the first time; An anecdote like this does nothing to scientifically quantify things and ignores countless amount of variables.
Wmaker, hundreds of quotes wouldn't be the perception of a single person, that would be the perception of hundreds... and quite frankly, I'm damned if I'll post any more here just to have you dismiss the words of heroes as so much toss. Starting to wonder why you're even involved in this if you have such little respect for those who served.
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SCTusk, to some searching , show me anywhere how a gyro creates a force not a torque.
Well golly g SCTusk, I think you just found the new engine, we can go to mars with just electricity and a gyro, quick you should call NASA.
HiTech
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So HiTech, all those satellites whizzing around over our heads being steered by gyros are actually not working at all? I'd better get straight onto NASA lol. Have a little think here; if you could get the rotary engine working in space, found some purchase and pushed the tail around, the gyro effect would work almost exactly as already explained. It does not require air, lift, wing coefficients or a khaki paint scheme. This is a fundamental force of physics, if you shove the thing one way it goes another. The energy for the motion comes from the spinning mass. Ask someone you do respect, that would know (e.g. a professor of physics... they love being asked stuff like this).
Controlled momentum gyros are rotated to change the attitude of a satellite as rapidly as possible by rotating them along a great circle path on an imaginary spherical surface around the satellite. Adjustments the gyro rotations are made in two directions, along the spherical surface, as the satellite rotates. All the stored angular momentum in the gyros is used to rotate the satellite, rather than limiting the rotation of the gyros to avoid instabilities from singularities in traditional control laws.
http://www.freepatentsonline.com/6154691.html
SCTusk again you are talking pure BS with out any research or knowledge.
Notice key words (change the attitude ) I.E. rotate the object not move it or a better word translate it.
It requires a translational force not a torque to turn an airplane.
HiTech
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http://en.wikipedia.org/wiki/Control_moment_gyroscope (http://en.wikipedia.org/wiki/Control_moment_gyroscope)
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"A control moment gyroscope (CMG) is an example of a fixed-output-gimbal device that is used on spacecraft to hold or maintain a desired attitude angle or pointing direction using the gyroscopic resistance force." <----- Force
ref http://en.wikipedia.org/wiki/Gyroscope (http://en.wikipedia.org/wiki/Gyroscope)
And that's twice now with the BS thing, but s'ok I'm still smiling :cool:
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SCTusk somehow you've missed the fact that gyroscopic precession is modeled on all
AH aircraft. You seem to think that Hitech explaining exactly how gyroscopic precession works is instead a denial of it's effects. Perhaps if you reread this thread you'll see my point.
Edit: If you aren't seeing any gyroscopic effects flying the Camel I may be able to help you with that in the training arena.
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"A control moment gyroscope (CMG) is an example of a fixed-output-gimbal device that is used on spacecraft to hold or maintain a desired attitude angle or pointing direction using the gyroscopic resistance force." <----- Force
ref http://en.wikipedia.org/wiki/Gyroscope (http://en.wikipedia.org/wiki/Gyroscope)
And that's twice now with the BS thing, but s'ok I'm still smiling :cool:
Note the specific in your own statement (btw statement resistance force is really a resistance torque.) but note how it is said more clearly "desired attitude angle or pointing direction" (no where does it say control direction of flight) This is exactly what I am trying to explain to you. It can rotate the aircraft but it can not "TURN" the aircraft, no matter what you do with the gyro it will continue to travel in a straight line (pointing direction may change) but the direction of travel will not.
HiTech
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Btw the satellite is a great example of a plane, in the exact same set up lift is acting like gravity creating the orbit or circle. The gyro can change the pointing direction just like the plane, but it will not in any way directly change the planes flight path just like the satellite will continue it's exact same orbit no matter what the gyro does.
HiTech
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All practical applications of the gyroscope are based upon two fundamental properties of gyroscopic action: rigidity in space and precession. The one of interest for this discussion is precession.
Precession is the resultant action, or deflection, of a spinning rotor when a deflecting force is applied to its rim. when a force is applied, the resulting force takes effect 90° ahead of and in the direction of rotation.
(http://www.332nd.org/dogs/Flushed/Gyro1.jpg)
The rotating propeller of an airplane makes a very good gyroscope and thus has similar properties. Any time a force is applied to deflect the propeller out of its plane of rotation, the resulting force is 90° ahead of and in the direction of rotation and in the direction of application, causing a pitching moment, a yawing moment, or a combination of the two depending upon the point at which the force was applied.
(http://www.332nd.org/dogs/Flushed/gyro2.jpg)
http://www.faa.gov/library/manuals/aviation/pilot_handbook/media/PHAK%20-%20Chapter%2004.pdf
The Camel in the game does turn better to the right than to the left. Have you experienced the wing stall when you try to turn left in a high banked turn in both the DR1 and F1? That is because the left wing was designed to provide more lift than the right to off set the effects of torque. In fact I believe the camel turns left better than the DR1. I also think the Camel is better suited as an E-fighter than the DR1.
And your quote from wikipedia "Because of the faster turning capability to the right, to change heading 90° to the left, many pilots preferred to do it by turning 270° to the right." how many ft is that is it 200', 300'.
As for the camel yes it enters a turn faster than a Dr1 from my experience but when the Dr1 gets to turning it can inside your turn and shoot you. I think the camel is better suited for the BnZ attack rather than the turn and burn.
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So after all this we have two observations.
1. The Camel in this game is gamey????????<----I trust HiTech to do his research so I don't think this observation is valid.
2. The torque of the rotary engine in the Camel will allow you to roll your right wing down faster than your left wing. This means you can place yourself into a right hand banked turn faster to the right due to the engine torque assisting the speed at which you can drop your right wing.<-----You can see the effects of massive torque during gunnery when you attempt to fine control your aim using the rudder. Left rudder and you track high over the target. Right rudder and you track low under the target.
Unless the OP is talking about the theoretical 4D wave and how high speed plasma streams at the edge of a gyro rotational object appear to act independently of the earths gravitational force.
But then a gyro rotational disk only wants to stabalise itself because it's evenly distributed around it's axis, not take off in a direction. But, in the plain of its rotation it's torque will effect a body attached to its axis by rotating the body in the direction of the plates spin. The propeller then has the problem with wanting to pull the aircraft to the left or right hand which is more sailent to the actual turn. Remember all that rudder on take off? The only thing the roatary engine can do is effect how fast the Camel rolls its right wing down. Obviously it did it better than any of the german designs in WWI.
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Btw the satellite is a great example of a plane, in the exact same set up lift is acting like gravity creating the orbit or circle. The gyro can change the pointing direction just like the plane, but it will not in any way directly change the planes flight path just like the satellite will continue it's exact same orbit no matter what the gyro does.
HiTech
Finally we reach Base Camp :) Now it's just a couple of short ascents over what will probably still be rocky ground.
Having changed 'the pointing direction' on the aircraft (your words not mine) as a result of gyroscopic precession (how far and how fast? That would depend on the aircraft) all we need to do now is wait to see what the conventional flight forces do with the new 'pointing direction'. I don't know your calculation cycle rate (how many steps you use per second) but I'd imagine it's quite high. Each step would no doubt show some change in the thrust vector, the lift vector, etc etc. Each cycle would feed more gyroscopic precession into the mix as the pilot continues the turn. The aircraft won't fly sideways for long, the extra lift under the port wing and thrust will soon take effect. And another cycle. Then another. Pretty soon were pointing back the way we came, our turn radius is shorter than conventional flight allows, our turn rate is quicker than conventional flight allows. Airspeed under the starboard wing may drop off so much we suddenly spin, but we're able to control the turn and avoid it using left rudder. Sound familiar?
Camel pilots reported a sensation of turning on the spot with a strong rush of air on the left side of their faces. I'm wondering why the testimonials of these men are being ignored. I find it hard to believe that as the creator of this simulation you would simply dismiss their comments. I prefer to think that you'll keep an open mind, look closely at the evidence, do a 'hands on' experiment or two - you can't beat it for getting a good grasp on the issue, seriously; it's vital before you walk away to have a spinning mass in your hands which you can turn around - and perhaps also consult with a university.
I've been accused here of not providing sufficient evidence. I disagree. In any case, if the guy across the road from your place left his car lights on, but when you tell him he doesn't believe you, is it your responsibility to take supporting photos, measure current drain on his battery and then maybe find his car keys and switch them off? Or do you just pop over and give him a 'heads up', then go about your business? And before anyone jumps in, yes I'd like to see them switched off too but not enough to get a head of steam up.
http://www.youtube.com/watch?v=8H98BgRzpOM&NR=1 (http://www.youtube.com/watch?v=8H98BgRzpOM&NR=1)
http://www.youtube.com/watch?v=2pYi3-q_IVA&NR=1 (http://www.youtube.com/watch?v=2pYi3-q_IVA&NR=1)
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You only provide anecdotal evidence from wikipedia and youtube. I can see by your use of the term "show some change in thrust vector, and lift vector" that you really don't know much about airplanes and what makes them fly. I believe there are only 25, not sure, aircraft types that can change there thrust vector and the camel isn't one of them.
Show us how many ft it takes to turn right in a real Camel as opposed to the game. Then show us how many ft it takes to turn right in a DR 1. you like quotes from old guys here is one. You may have heard of it.
Actioni contrariam semper et æqualem esse reactionem: sive corporum duorum actiones in se mutuo semper esse æquales et in partes contrarias dirigi. - Isaac Newton
it means: whatever draws or presses another it is as much drawn or pressed by that other.
He may report a sensation that he turned on the spot but if he really did one of 2 things would happen. All the blood would rush from his head to his feet and he'd black out or atmospheric pressures would tear the plane apart. Planes are designed only to take so much g loading. I don't know the exact numbers but for a world war 1 plane I'd say around 6.
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SCTusk you continue to confuse rotating with turning. What you describe already happens in game. It's hard to believe you've flown the AH F1 and not noticed the torque that you claim is missing. Do you have the stall limiter turned on?
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He may have not turned off the engine limiter. I forgot to check today with the new game version and got spanked in the WWI arena. By default the new install turns it back on. Wondered why it was so tame and stalled me out in every engagement.
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Each step would no doubt show some change in the thrust vector, the lift vector
Not really , the pilot would just compensate with controls and the plane would fly the same.
So as I said at the very beginning control forces could cause extra drag but very minor. And also there would be extra control force in both directions of the turn it is not as if the gyro works one way and not the other.
Camel pilots reported a sensation of turning on the spot with a strong rush of air on the left side of their faces. I'm wondering why the testimonials of these men are being ignored. I find it hard to believe that as the creator of this simulation you would simply dismiss their comments. I prefer to think that you'll keep an open mind, look closely at the evidence, do a 'hands on' experiment or two - you can't beat it for getting a good grasp on the issue, seriously; it's vital before you walk away to have a spinning mass in your hands which you can turn around - and perhaps also consult with a university.
Nothing is being ignored. Your turning left, nose is yawing right or up, hmm plane is slipping, hmm feel wind from left side of face if you do not put in rudder. Also all your comments so far would be nothing special to the camel, they also happen on the dr1.
I find it hard to believe that as the creator of this simulation you would simply dismiss their comments.
I find it very hard to believe that you do not give the creator of 2 flight simulations over a 15 year period a little credit for knowing physics , Also a pilot who flys a tail dagger and feels the gyro effects on every take.
And you once again prove with your this post that you are really talking pure bs and grasping at straws to make your desire true. And if you look closely I have never stated one thing about the camel vs other planes, I have just been shining a light on the statements you make about physics that have no basis in fact.
HiTech
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I'm sorry you feel this way HiTech, I certainly do have respect for your knowledge and experience (clearly this isn't reciprocated lol). Presumably though there may be the occassional thing which comes along where you probably take some pleasure in learning something new as I certainly do myself. I have been trying to the best of my ability to communicate what I believe to be just such a thing, all the while maintaining what I hope is a good humour and friendly disposition.
I have at least arrived at a simple experiment which anyone should be able to arrange (and surely considering the strength of opinion against my proposition one which anyone involved in this thread thus far should be eager to perform). As a group of aviation enthusiasts I'm confident that most of us have access to some form of small model aircraft with an electric motor driving a propeller, a childs toy perhaps or something more serious but small enough to suspend from the ceiling by cotton or string in an approximation of a level flight attitude. Aside from any scientific considerations this experiment is great fun :)
The purpose of the experiment is to examine the effects of gyroscopic precession on an aircraft in motion (specifically in a turn).
The experiment initially requires the motor to be turned off. If there are any control surfaces they should be in the neutral position. The aircraft should be released with the suspending thread taut, at a point removed from the centre of suspension (i.e. off centre) with enough impetus for the momentum to carry it around in a circle. Care should be taken at all times not to allow the suspending thread to become overly twisted, otherwise an undesirable torque might act on the model. If the model is not too heavy for the intended purpose observation should confirm that as it moves around in a circle the nose always points approximately forward. To confirm that there is no bias the test should be conducted in both directions, i.e. left and right hand circles.
All being well we can now turn the motor on and repeat the tests in both directions. (a propeller is actually unnecessary as it is the gyroscopic effect of the motor we are testing, but if the model has one it should not affect the result greatly). Observation should confirm that the model travels around in a circle with the nose forward as before in one direction but not the other (direction dependent on motor spin direction).
At this point the rudder or fin should be moved from the neutral position to the left yaw position and the test repeated in both directions, then subsequently to the right yaw position with the test again repeated in both directions. Observation should confirm that in the direction favoured by gyroscopic precession the model can be made to turn around a very small radius, whereas in the unfavourable direction only large radius turns are possible.
In this simple experiment we made use of a suspending thread as a substitute for lift. Depending on the model used it is possible that the airspeed attained during the testing is insufficient to provide lift, and an argument could be made that this renders the test invalid. However, since the purpose of the experiment is to examine the effects of gyroscopic precession on an aircraft in motion the airspeed need only be sufficient to act appropriately on the fin and rudder.
Conclusions.
An effect was noted which appeared to continuously assist the model to turn in one direction, and continuously resist it in the opposite direction. It would seem safe to assume that gyroscopic precession caused the effect, that it acted continuously due to the continuous change of direction of the model, and that the extent to which this affected the model is a matter of degree. It can be further concluded that given a sufficiently large effect (i.e. by manipulation of factors such as balance and distribution of mass in the aircraft, mass of rotating body, speed of rotation of mass, aerodynamic properties of the aircraft) it would be possible to create an aircraft capable of extreme minimum turning radius in one direction at the expense of a large turning radius in the opposite direction.
It is quite possible that someone might get different results to those outlined above; or that they might draw different conclusions. I think the nature of the investigation having so much contradictory evidence and being such an unfamiliar phenomenon makes it one of enormous interest. Certainly a search on the net shows multiple instances of this very topic, always with similar polarisation of the contributing posters.
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SCTusk, I have a better way for you to test. Jump in the camel in AH make coordinated turns to right and left and time them.
HiTech
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I just finished an experiment. I used a standard toy gyroscope you can purchase from a toy store.
1. I mounted the gyro by its axis post into the end of a rod.
2. The Camel looks like its CG is about 1/5 back from the gnome rotory so I counter balanced the rod at that point.
3. I created a heavy base with a verticle rod mounted into a race bering.
4. I mounted the balanced gyro/rod across the end of the verticle rod so it freely rotated in any direction horizontal to the ground.
5. I wound string onto the gyro and left fly with a right hand twist.
6. It just sat there with the gyroscope spinning. I had to lift the base at which point I could make the gyro/rod move left or right.
Conclusion: You need a propeller to cause induced yaw which you correct with your rudder.
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On to the next experiment, which is a work in progress. Those familiar with radio control model aircraft would no doubt be aware of the current trend of using brushless electric motors rather than internal combustion engines. One common type used is the outrunner which has a large spinning mass, making it an ideal scale substitute for the rotary engine. I have a small collection of models, some of which are thus equipped. Here's a link to an onboard video of a semi-scale F4U Corsair which I tend to fly fairly conservatively for a number of reasons:
http://www.youtube.com/watch?v=wPmmG9tzpfE (http://www.youtube.com/watch?v=wPmmG9tzpfE)
The video only proves one thing - my r/c skills are average at best. But I can attest to the fact that this model, which has the motor well forward of the CG, can turn 180 degrees to the right in very short order. Left turns however are much more sedate.
I have a box with the remains of an outrunner equipped Harvard (similar to the Texan) which I'm sure you will know has a short nose with most of the mass near the CG. It gave me some nasty moments on the maiden takeoff, yawing and dropping its' wing etc, but seemed to settle down ok into the usual left hand circuits. After a few minutes I relaxed and decided to put it through some manoeuvres, but I wasn't up to the task of simply turning sharply right (instantaneous right hand spin) and thus the box of bits.
I can think of several scientific objections to comparing models with full size aircraft, but I wanted to make it clear where my opinion originates; I can't help what I see in the behaviour of these aircraft, and if they 'snap' turn in spectacular fashion to the right yet fly sedate left turns (which they seem to do) I find myself more inclined to believe the anecdotal pilot reports about the Camel. If the experiment were likely to be well received (and I doubt this judging by reaction so far in this thread) and if I had the necessary flying skills I would be only too ready to build a semi-scale Camel and conduct whatever tests were deemed useful. But the minor disaster with the Harvard shows that the effect is so pronounced in such aircraft that I lack the experience to tame them.
For the record, I took HiTech's advice and timed some co-ordinated turns in the Camel, which did show a tendency for more rapid turns to the right (possibly as much as 1 second, or about 10% but I was unable to fly neatly enough to be certain). So it would seem there might be something going on in there which I had been previously unable to detect. If so, then the entire question is more a matter of degree.
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Does this mean I have to give the gyroscope back now?
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An extraordinary thread, and surely some kind of record for someone on his 37th post and his first month in the game.
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The video only proves one thing - my r/c skills are average at best. But I can attest to the fact that this model, which has the motor well forward of the CG, can turn 180 degrees to the right in very short order. Left turns however are much more sedate.
Basically, you're using the torque to roll into your turns. Since the torque is to the right, you're plane is going to roll in that direction faster than it would be if you fought against the torque and rolled to the left in the turn. The torque itself isn't providing the forces to turn the plane, it's just rolling it to one side.
ack-ack
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Any topic that can combine gang signs,
(http://upload.wikimedia.org/wikipedia/commons/thumb/7/79/Rechte-hand-regel.jpg/220px-Rechte-hand-regel.jpg)
and differential equations,
(http://upload.wikimedia.org/math/c/4/9/c49a55b22e60e33a76a6de4d9ee6f332.png)
has to be considered and excellent discussion. ;)
I haven't done this much reading/research and math in a long time.
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lol enjoyed that :aok
Basically, you're using the torque to roll into your turns. Since the torque is to the right, you're plane is going to roll in that direction faster than it would be if you fought against the torque and rolled to the left in the turn. The torque itself isn't providing the forces to turn the plane, it's just rolling it to one side.
ack-ack
I think there's some confusion regarding the use of the term 'torque' here, which is why I changed tack from my original post and tried to refer to it as a force; although HiTech says it's actually a torque, so I'm happy to call it such. Problem is we now have two 'torques', the first is the usual torque of the motor, while the second is the gyroscopic effect as discussed, which manifests itself in a perpendicular direction to the axis of rotation, 90 degrees offset to the applied force (the force which is applied to the spinning motor as the aircraft turns).
As HiTech was quick to discover, my knowledge of vectors and this type of maths is limited to some barely remembered head scratching in final year physics a very long time ago. So I'm content to leave that side of it to those more familiar with it. I'm more concerned with the initial 'hands on' awareness of the concept, and observable (and repeatable) real world results which might either confirm or refute the anecdotal evidence. Here's a link to a fun and informative video on gyroscopes:
http://www.youtube.com/watch?v=cquvA_IpEsA (http://www.youtube.com/watch?v=cquvA_IpEsA)
As the video shows, there is an effect at work which seems capable of moving the spinning mass in a way which could cause the effects suggested by the pilot reports, with the second question being if so, to what degree? Unfortunately I have been unable to discover much about the effect in AH. I am simply assured that it is modelled. There seems to be some evidence of the effect (in the turn) but I would have expected it to be more pronounced (based on personal experience and the anecdotal evidence).
Reading through the thread again it seems that I should have made it clear from the outset, I would certainly not want any change made to the Camel FM if the evidence suggests otherwise.
But it would appear that unless you hold a degree in Physics you are not encouraged to participate in such a discussion here. I am not aware of any scientific endeavor where a general 'real world' or 'hands on' understanding of the material is not encouraged, usually prior to the technical details being considered.
I have the highest regard for HiTech and his team for producing an extremely convincing simulation. I would not want anything changed unless there was conclusive - or as near conclusive as could be obtained - evidence to justify such change. The evidence of my own eyes and hands convinces me, but perhaps I suffer from the confusion of the layman. Someone tell me then, in simple lay terms, why does the gyroscope defy gravity in the video? And why would the 'force' or 'torque' (call it what you will) not impact on the flight characteristics of the Sopwith Camel?
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The force you are missing is the force from the table transmitted via the little black stand. In essence the gyro is changing the down force of gravity combined with an up force up force of the stand (creating a torque ) to a torque 90 deg to the fly wheel.This torque in the 90 deg rotation is then trying to rotate the gyro about its center of mass. Since the one end is fixed horizontally the rotation is resisted by a force from the stand and hence the net force roates around the stand.
This is very similar to what I have said in the beginning , only in this case the force we a speaking of is not trying to rotate the gyro down like gravity, but rather we are trying to rotate it horizontally and the gyro is trying to change the rotation to the vertical plane hence either lifting or lowing the nose. But you are still thinking of turns as rotation, instead of changes in direction like the stone in the video.
But it would appear that unless you hold a degree in Physics you are not encouraged to participate in such a discussion here. I am not aware of any scientific endeavor where a general 'real world' or 'hands on' understanding of the material is not encouraged, usually prior to the technical details being considered.
This is pure bs, but if you wish to discuss a matter and try to argue basic physics, we would expect you to at least attempt to learn the subject matter being discussed and possibly except what people who do study this stuff generally know what they are speaking of.
I think there's some confusion regarding the use of the term 'torque' here, which is why I changed tack from my original post and tried to refer to it as a force; although HiTech says it's actually a torque, so I'm happy to call it such. Problem is we now have two 'torques', the first is the usual torque of the motor
You do not just have 2 torques you have the sum of many in which the total is described as 3 terms, each a torque about an axis, or in airplane terms roll pitch and yaw.
As the video shows, there is an effect at work which seems capable of moving the spinning mass in a way which could cause the effects suggested by the pilot reports, with the second question being if so, to what degree? Unfortunately I have been unable to discover much about the effect in AH. I am simply assured that it is modeled. There seems to be some evidence of the effect (in the turn) but I would have expected it to be more pronounced (based on personal experience and the anecdotal evidence).
And this is where you start to get your self into trouble. The net effect of the gyro scope really comes down to 3 numbers. RPM of prop, Moment of inertia of the prop, moment of inertia of the plane. I have documents showing these numbers, and hence unless the documents are wrong (doubt full) or we typeoed the number, the effect would be correct.
Unfortunately I have been unable to discover much about the effect in AH.
What exactly is it you wish to discover about the effect? I don't believe you have even asked anything about the effect in AH. And other then the exact numbers, (which I do not believe would help you anyway). The effects are simple and can be verified, yaw left nose pitches up, yaw right, nose pitches down. Pitch up plane will yaw right, pitch down plane will yaw left.
HiTech
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RPM of prop, Moment of inertia of the prop, moment of inertia of the plane.
HiTech
I presume you mean moment of inertia of engine? Or are you just modelling the spinning prop?
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In a discussion prior to the release of the WWI planes HTC stated that the gyroscopic effect of the DR.1 and F.1 Camel would be significantly higher due to their rotary engines. They are modeling the spinning engines.
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I presume you mean moment of inertia of engine? Or are you just modelling the spinning prop?
Yes I was including the mass of the engine with the prop.
HiTech
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What exactly is it you wish to discover about the effect? I don't believe you have even asked anything about the effect in AH. And other then the exact numbers, (which I do not believe would help you anyway). The effects are simple and can be verified, yaw left nose pitches up, yaw right, nose pitches down. Pitch up plane will yaw right, pitch down plane will yaw left.
HiTech
So in a sustained right hand turn (for instance) which requires an element of (a) pitch up plus an element of (b) yaw right, the gyro effects on the aircraft will be (a) yaw right and (b) pitch down?
I'm fairly sure that's what I suggested in the beginning. I ask so that I can be clear on your position because earlier you accused me of talking BS when I suggested that gyroscopic effects could assist the aircraft to turn.
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So in a sustained right hand turn (for instance) which requires an element of (a) pitch up plus an element of (b) yaw right, the gyro effects on the aircraft will be (a) yaw right and (b) pitch down?
I'm fairly sure that's what I suggested in the beginning. I ask so that I can be clear on your position because earlier you accused me of talking BS when I suggested that gyroscopic effects could assist the aircraft to turn.
Correct, simply draw a line straight down from the turn circle, how the line passes threw the plane in its banked to the right will be the resultant torque of ( down pitch and right yaw). But note, that is in no way assisting the aircraft turn, it is providing a torque perpendicular to the turn. Just because an aircraft is yawing right in a right turn, does not imply an assist to the turn. The yaw is generally stated in a plane relative direction. So as you can see in the case of a 90 deg bank, you would only have a yaw force and no pitch, but that yaw would not be in the direction of the turn. That yaw is not in the direction of the turn and hence in no way assisting it. And you are still confusing the terms turn which in this context refers to a change in the inertia (a liner direction/translation change) which is created ONLY by lift and thrust,and nothing to do with torque on the plane. The gyro would be capable of rotating the plane, but it would still be flying in a straight line.
As I have been trying to explain, and you seem to not clearly see the difference between rotation and translation forces/torque. It is impossible for a gyro to CREATE a translation force. In your example of the right hand turning plane, the rudder would then be pushed left and up elevator applied to put the plane at max aoa and remove the slip caused by the gyro. The extra control input in both rudder and elevator would cause a very slight increase in drag and in the right had turn create a net force in the down direction. So in the right hand turn just as in the left the gyro works against your right hand turn do to the extra drag created by the controls.
HiTech
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Thanks HiTech for taking the trouble of phrasing the above in terms I can understand. I trust this thread hasn't tested your patience too much, I expected worse than the occassional reference to 'BS' and consider myself lucky you have confined yourself to that alone. My old flying instructor had the habit more than 30 years ago of kicking my butt sharply from the rear cockpit whenever I was slow to pick something up lol. I like to think his efforts weren't wasted and hopefully yours won't be either. If at the end of the day I appear to not fully understand the concept then perhaps others reading this thread will get something from it.
If I may just revisit the salient points of the discussion on which I think we agree, if I state anything incorrectly please do not hesitate to correct me (I will attempt to use your preferred terminology for clarity, but I will use the term 'gyroscopic effect' rather than 'gyroscopic precession' but meaning the same thing).
btw I'm referring to a gyroscope as I do this so hopefully I'll get it right lol.
1. In consideration of a spinning mass rotating around (e.g.) the X axis. When a torque is applied around the Y axis a gyroscopic effect or torque is produced around the Z axis. Similarly when a torque is applied around the Z axis a gyroscopic torque is produced around the Y axis.
2. In the absence of additional torque or resistance this reactive gyroscopic torque will cause the spinning mass to rotate around either the Y or Z axis as indicated above.
3. The power of the reactive torque is directly related to the mass, the rate of revolution of the mass, and the power of the initiating torque.
4. The reactive torque is instantaneous to the initiating torque.
5. It follows that in a clockwise (viewed from behind) rotary engine aircraft a pitch up movement will create a yaw to the right, a pitch down movement will create a yaw to the left, a yaw to the right will create a pitch down and a yaw to the left will create a pitch up.
6. It further follows that in a right hand 45 degree banked co-ordinated turn (e.g.) the aircraft will require some degree of left yaw and pitch up input to achieve a co-ordinated or 'balanced' flat turn.
As I said, if there are any anomolies in the previous statements please respond accordingly. In the meantime I will assume we are in accordance on these significant points. I don't think there's anything here so far that runs contrary to my own initial assumptions (other than terminology) so if you are happy with it I presume we have been more or less 'on the same page' at least in regard to these basic principles.
I have something further to add but prefer to get these points clarified before proceeding.
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SCTusk:
I don't see anything I disagree with other then some very minor term stuff.
HiTech
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Being a tad lazy, - I have a simple question, which may have been answered somewhere in the debate.
Would there be any difference between the effect of a rotary engine and another sort apart from the rotary being able to "snap" the aircraft faster into one direction?
Just me maybe,,,,but I have to fix washing mashines all the time, and there is a reason while the lid is supposed to be locked....
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there is a reason while the lid is supposed to be locked....
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.....to keep out little fingers.
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Every time I try and read this thread I find myself dreaming of camel toes and quickly lose interest in airplanes.
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Angus There are many differences between the different planes, esp between WWI and WWII.
However, even a 109g2 rolls considerably faster to the right than the left.
In effect to roll left you either roll slow, or cut the throttle to reduce the torque.
All you need is a stop watch, and a repeatable flight pattern. Ie same plane, same alt, same airspeed, etc.
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Thanks HiTech, I'll try to restrict myself to referencing the points in the previous post, that way if I go off the rails you should be able to point out the errors in a way I can follow.
At this point I would like to address the following question: Could rotary powered WW1 aircraft turn better (either at a higher rate or shorter radius) to the right than to the left as a result of gyroscopic effect?
In reference to points 5 and 6 in my previous post, it can be seen that a different condition occurs when the aircraft turns to the left (as opposed to the right) :
In a left hand 45 degree banked turn the gyroscopic effect will cause a pitch up and a yaw to the right. As the aircraft is banked at 45 degrees some amount of pitch up is required anyway, but it should be noted that if the effect were large enough some pitch down input may be required. At this time I will assume that all that is required in this instance is a reduced pitch up input to maintain the turn. The yaw to the right must be countered with some amount of left yaw input in addition to the left yaw input normally required in the absence of gyroscopic effect.
So to outline the differences between similar co-ordinated left and right turns under gyroscopic effect :
The left turn requires more left rudder than usual and less pitch up (or possibly even pitch down under extreme effect).
The right turn requires left (opposite) rudder and pitch up.
Consider the conditions for a tighter turn, which would require a higher angle of bank and more input to counter the increased gyroscopic effect. Assuming that sufficient airspeed is maintained (especially on the wings on the inside of the turn) the limiting factor to increasing the left turn is the limit of rudder travel. Once this limit is reached the turn cannot be made tighter as the gyroscopic effect will cause the aircraft to yaw to the right, which goes against the turn. Any further pitch up input increases the yaw to the right (due to gyroscopic effect) negating the effect of increasing pitch in the turn.
The limiting factor to increasing the right turn however is not the limit of rudder travel. The rudder is being held to the left to counter the yaw to the right, so if the rudder reaches the limit of travel in this case the aircraft will yaw right, which goes with the turn. Put another way, we actually want more yaw to the right as we tighten the turn. Additional pitch up input will increase the yaw to the right, so that the turn can be tightened provided the limit of elevator travel is not reached (in reality the aircraft is more likely to stall a wing before this occurs). At this stage the right turn will no longer be co-ordinated due to the left yaw input being at maximum yet insufficient, but with the error in co-ordination favouring the turn rather than going against it.
Since the rudders on these aircraft are known to have been insufficient (I believe there was some misunderstanding of the basic design principles at the time?) I suspect that the limit of rudder travel might have been reached quite quickly in the presence of a substantial gyroscopic effect. My contention therefore is that the rotary engined aircraft were capable of tighter turns to the right than to the left.
If I have made this argument correctly there is still the matter of degree, not only in general but in relation to the Camel versus the Dr1. However there seems little point in pursuing those questions without your acceptance of this initial premise.
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First you are asking a slightly different question then originally spoke of, you are asking can a gyro slow a left turn more then slowing the right turn, VS can a gyro speed up a turn.
Ill give you a more detail analysis later but your first major error is this.
Consider the conditions for a tighter turn, which would require a higher angle of bank and more input to counter the increased gyroscopic effect. Assuming that sufficient airspeed is maintained (especially on the wings on the inside of the turn) the limiting factor to increasing the left turn is the limit of rudder travel. Once this limit is reached the turn cannot be made tighter as the gyroscopic effect will cause the aircraft to yaw to the right, which goes against the turn. Any further pitch up input increases the yaw to the right (due to gyroscopic effect) negating the effect of increasing pitch in the turn.
And specially
effect will cause the aircraft to yaw to the right, which goes against the turn.
Yes on yaw right and up but the torque is not against the turn, it is 90 degrees to the turn or up, it is in no way against the turn. As you run out of rudder (assuming this is the case, it would be very plane specific and that is a different topic) you would simply be slipping the plane in the turn. And this slip would happen if turning either direction creating drag and hence slowing the turn both left and right.
2nd the limiting factor in the turn is MAX AOA (I.E. stall) not the rudder.
HiTech
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Ok lets first describe some terms and how an aircraft turns.
Turn/revolution (to move about a circle) think of this as an airplane moving about a circle always pointing north.
Rotate (to pivot about an axis) picture this as an airplane not moving but spinning like a top.
How an airplane turns ,as the plane banks to the left, the lift vector is pointed side ways, this force to the left accelerates the airplane to the left and the airplane is now moving in a slightly different direction and hence the wind is traveling at a different angle across the plane.
Now since the wind is from a different direction it pushes the the tail of the air plane creating a torque and rotating the plane.
This process continues and the plane turns and pivots as it travels about the circle.
So please note very carefully what really TURNED the airplane was the horizontal component of lift.
Now since we banked the lift vector the plane started descending causing the pilot to pull the stick back, causing a torque on the plane , rotating the plane creating a larger AOA, and creating more total lift, enough until the up component of the lift vector = the weight of the plane.
As the plane banks more, more total lift is required and generated for level flight by pulling on the elevator also creating more horizontal force and hence accelerating the plane to the side more. Now for any bank angle the total up force will be 0 (gravity - lift). The total torque on the plane will also be 0 because if we have an net torque or net force on any object by definition it will accelerate its rotation or its translation.
The horizontal component of the lift is not 0 and accelerating the plane in the horizontal, 90 degrees to its direction of travel.
Now onto the gyro problem.
The plane is Turing a circle parallel to the ground.
The gyro is is spinning around the tangent of the circle, As the gyro moves/ translates around the circle it is also rotated as described above.
This rotation creates a torque either up or down. (basic gyro principle) So far I am fairly sure you agree.
Now if we were doing a flat 0 deg bank turn (not reality) all this up or down torque would have to be offset by use of the elevator.
Now if we were flying a 90 bank angle (again not reality) all the up or down torque would be controlled with the rudder.
Now at any bank angle in between 0 & 90 the up or down torque is controlled with a combination of rudder and elevator but to maintain the same rotation rates (note not turn rate, the rotation rate simply must match the turn rate) and hence must create a net torque of 0 on the plane. Now if the gyro was not there again the net torques would have to be zero. Since the gyros torque is up, the only thing that can be added is a net torque in the opposite direction. If we add any other net torque we are accelerating the rotation and this would either spin the plane on its tail or cause it to stall, because in a steady state turn all torques must sum to 0.
To view this view the plane in a 45 deg bank,you would have a 45deg force from the rudder and a 45 deg force from the elevator like legs on a saw horse. The horizontal forces must = each other and the vertical force * the arm must = the torque created by the gyro.
Hence we have not created any net extra horizontal force and thus the plane can not turn faster.
Now the other piece in involved. As I stated very early on the only thing that could possibly change the turn rates is the net drag on the plane. If for some reason (I have not been able to think of one, but I am not positive) more drag is applied turning left then turning right it do to the gyro it would effect the turn rate, simply because increasing speed increases turn rate.
HiTech
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Bravo HT <S>
And thank you sir.
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Thanks HiTech. I have two problems with your previous posts. I know you must be very busy and this is just one of many items on your to-do list, so I will presume a 'slip of the tongue' but I must still point to the errors so my apologies in advance. Firstly you neglected to mention thrust. Lift and drag are effects brought about by thrust, therefore are subordinate to it. Second you refer to my mention of adverse yaw in a turn as not being against the turn, but rather 90 degrees to the turn. But you are referencing a point along the line of lift directly above the centre of the turn. This point is not the centre of the turn. The centre of the turn is in the same plane as the turn, i.e. directly below the point you are referencing and not somewhere along the line of lift. As I will demonstrate this is vital in understanding the significance of adverse yaw.
In a turn the line of thrust would usually be approximately tangential to the arc of the turn and acting in the direction of the turn. If an effect were to cause the thrust to be directed as in say, a right yaw in a left turn, then that is an adverse yaw, i.e. away from the centre of the turn due to the thrust now working against the turn, or if you prefer moving you away from the centre of the turn. If however the thrust was directed towards the centre of the turn instead of away from it, as in say, a right yaw in a right turn, that is the opposite of an adverse yaw, or you might say the yaw is assisting the turn due to the thrust moving you closer to the centre of the turn.
If I could demonstrate with a hand experiment; left arm straight out to the side then swing forward 45 degrees, left hand represents centre of turn circle. Right arm straight out to the front, palm flat down, hand represents aircraft in level flight viewed from the rear. Add 45 degrees of left bank. So far so good. Now add 45 degrees of right yaw. You can clearly see that there is no way the thrust line is going to help you move around the centre of the turn circle (left hand). Now yaw 90 degrees back to the left and observe that although the 'aircraft' is in a nose down attitude, the thrust line is now positioned so as to assist the turn.
But here's the really fascinating part, which I initially missed due to over simplification in my previous post. I will now consider secondary effects in the aforementioned left and right gyroscopic turns:
1. Left turn induces gyroscopic effects of right yaw (adverse yaw) and pitch up. Secondary effect of right yaw is bank right (adverse bank). Pilot induces left bank to counter, inducing secondary effect of ailerons i.e. right yaw (adverse yaw). A total of three adverse effects in what I think you will agree is a closed loop of cause and effect. There seems to be nothing the pilot can do to prevent the aircraft skidding out of the intended turn.
2. Right turn induces gyroscopic effects of right yaw and pitch down. Secondary effect of right yaw is bank right. If pilot corrects with left bank secondary effect of ailerons induces right yaw. No adverse effects.
So it seems clear that if the gyroscopic effect is significant, the aircraft will be unwieldy in a left hand turn, but will turn right quite readily.
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SCTucks, 1st adverse yaw is typically refereed to as the yawing effect from ailerons do to differential drag but that is just a definition.
But what you are missing one big thing, the plane is in the exact same position as if it would not have gyro torques because the torque was corrected with a combination of rudder and elevator and hence the prop is not outside the turn and would be in the same position relative to the turn.
2nd even if the torque is uncorrected with controls and the plane is left to slip you are including 1 force and ignoring the force apposing it creating the 0 torque sum. In essence you seem to be hung up on rudder torques/forces working for you with out looking at elevator forces/torques working against you.
There seems to be nothing the pilot can do to prevent the aircraft skidding out of the intended turn.
This has me completely lost because it is obvious in almost any plane, (all prop planes have gyro forces) that the pilot can fly a non skidding turn. So why is a rotary any different except in the size of forces & torques? So are you claiming a plane can never fly a coordinated turn?
To summarize, the plane is in the same position relative to the tangent of the circle with or with out gyro torques. The pilot simply moved the controls to hold it in the same position.
So it seems clear that if the gyroscopic effect is significant, the aircraft will be unwieldy in a left hand turn, but will turn right quite readily.
Again read previously I have stated it is much easier to turn to the right then the left, this is obvious to anyone flying the rotary engined planes, but that is a different question then the turn rates. And is primary do to the planes tendency of slowing vs speeding up when flying uncoordinated.
HiTech
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One area I am beginning to investigate is how the WW1 aircraft were rigged at the time. Given that neither the F.1 or the Dr.1 had any trim controls the initial rigging would effect how the plane responds in flight.
My original assumption was that the planes would be rigged for cruising speed. However, given that takeoff and landing were very tricky, perhaps most planes were rigged to make low speed handling better. Or perhaps they chose a compromise between the two.
Now I know you liked my trim control setup HiTech at the last CON, so it's pretty easy for me to test.
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What is clear is why few developers engage in discussions with the public.
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"What is clear is why few developers engage in discussions with the public."
It is also clear that if the game has survived more than ten years, with players active all those years, it is also recommended.
-C+
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One area I am beginning to investigate is how the WW1 aircraft were rigged at the time. Given that neither the F.1 or the Dr.1 had any trim controls the initial rigging would effect how the plane responds in flight.
My original assumption was that the planes would be rigged for cruising speed. However, given that takeoff and landing were very tricky, perhaps most planes were rigged to make low speed handling better. Or perhaps they chose a compromise between the two.
Now I know you liked my trim control setup HiTech at the last CON, so it's pretty easy for me to test.
Baumer as you know the point of rigging is to lesson the pilot work load. Since you spend most of your time at cruise speed and altitude it makes sense that you rig for that condition. You're going to be active on the controls when taking off and landing regardless of the speed you rigged for.
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Thanks again HiTech, you state your case clearly (whereas perhaps I struggle a little) so that I can attempt to address your objections specifically.
the plane is in the exact same position as if it would not have gyro torques because the torque was corrected with a combination of rudder and elevator and hence the prop is not outside the turn and would be in the same position relative to the turn.
You would know the figures whereas I can only suggest that the maximum torque applicable with the elevators would significantly exceed the maximum torque applicable with the rudder. As the gyroscopic effect produces a torque equal to the inducing torque but at 90 degrees to it, this suggests that in hard turns the rudder would in fact not be capable of correcting the induced yaw from the initiatiating action of the elevators.
even if the torque is uncorrected with controls and the plane is left to slip you are including 1 force and ignoring the force apposing it creating the 0 torque sum. In essence you seem to be hung up on rudder torques/forces working for you with out looking at elevator forces/torques working against you.
I am not ignoring the opposing force creating your 0 torque sum, I am ignoring your torque sum. The whole premise of your equations is based on a point on the line of lift above the centre of the turn circle, not on the centre itself (i.e. on the same plane as the circle). I presume you employ this method in the simulation. In reality I'm sure you are aware that an aircraft in a left turn with right yaw must move away from the actual centre of the turn (unless the movement along the line of lift exceeds the movement along the line of thrust?) thus widening the turn as indicated in the hand experiment of my previous post. If that lacked clarity then imagine the following situation:
If you are turning to the left around a tree at tree height so that the tree is at the centre of the turning circle and allow the aircraft to go nose high and yaw right it becomes immediately obvious that the aircraft is pointing more than 90 degrees away from the tree, therefore must move further away from it.
I would think we could just allow that a skidding turn can not be a tight and efficient turn. Surely nobody would seriously argue this point. As you say, there would be increased drag for one thing. Also the nose will be high (both from the pitch up and the right yaw) slowing the horizontal movement of the aircraft around the turn as the aircraft attempts to climb.
Obviously all this depends on the degree of gyroscopic effect. I have assumed a significant degree in the discussion so far, so that the effect and its' result can be visualised more easily. If the degree of the effect in a hard turn proves small enough to be easily corrected in the turn, then my argument is invalid.
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SCTusk you are starting to change the discussion.
From the out set we stated we are speaking a general case not a specific case. You are now making assumptions that the plane can not fly coordinated and then really are changing the question to 3 questions.
1. Does non coordinated flight slow a turn.
We both agree yes.
2. Can a gyro produce enough force to be able to fly none coordinated.
A very plane specific question.
We would both agree that we can create a plane and condition that this is the case.
But these 2 questions are very very different then the statement a gyro makes your plane turn faster to the right. Which is the claim you made at the outset.
3. Exactly how and in what directions would this non coordination be in both left and right turns.
If the above is your premis, I have no desire to discuses the very plane specific items required for this.
If you believe a plane flying coordinated in a turn will turn more quickly right do to gyro torques , I will be happy to continue the discussion.
Also in this discussion if you arrive at only very minor force differences such as the different moment arms of the elevator and the rudder then again I have no desire because at this level of force many many other things must be considered and the precision we are starting to speak of no longer can be spoken of in a general since and would again be very plane specific.
Any way regardless of the above here is an analysis I have done of your post.
You would know the figures whereas I can only suggest that the maximum torque applicable with the elevators would significantly exceed the maximum torque applicable with the rudder. As the gyroscopic effect produces a torque equal to the inducing torque but at 90 degrees to it, this suggests that in hard turns the rudder would in fact not be capable of correcting the induced yaw from the initiating action of the elevators.
You have multiple premise problems here.
1. A gyro does not produce a torque = to the torque applied to it in a 90 deg direction. It only applies a % of torque that is calculated by rpm * moment and mass of the entire object. I assume one you think about it, this should be obvious, because other wish even a mass spinning 1 1 rpm would produce a torque 90 degrees to the applied torque.
2. The 2nd piece you are missing is that how much the rudder and elevator must applied are only = to each other at a 45deg bank. In all other case the amount required are related by a sin cos functions. As I stated earlier in a flat turn all elevator is needed, in a 90 deg bank all rudder is needed.
3. Using your argument you are stating you can not fly a max g loop with out skidding.
4. The forces need to generate the torques are very speed specific. So you could fly coordinated at one speed but slower you could not.
If you are turning to the left around a tree at tree height so that the tree is at the center of the turning circle and allow the aircraft to go nose high and yaw right it becomes immediately obvious that the aircraft is pointing more than 90 degrees away from the tree, therefore must move further away from it.
Think about what you just said, if the plane is continuing to move away from the center of a circle it can never return to the same point hence it is not flying circle.
Also note I am not saying that a thrust vector can not point out side the circle,and produce a force apposing the turn.Obviously if you allow the plane to slip it will turn slower, for many reasons not just the thrust vector. I am saying that if you are in a coordinated turn it will be in the same position regardless of gyro torques.
I am ignoring your torque sum.
If you do not believe that the sum of torques have to be 0, then we must back up and discuss this, because with out that premises we can not really begin. It is a basic technique used in problem solving and stems for the simple formula F = M * A, so if you are left with a torque or force after summing all torques and forces, the object MUST be accelerating in some direction or rotation.
The whole premise of your equations is based on a point on the line of lift above the centre of the turn circle, not on the centre itself
Your assumption would be completely false assume.
The core idea of simulation is very simple and is physics 101. You can take all torques and forces on any object and reduce them to 1 force vector and 1 torque attitude.
then F = m * a for both translation and rotation. Rinse repeat.
So thrust direction is very simple, what direction is the plane pointing, add thrust at the prop point in the direction the plane is pointing + any engine angle offsets.
And hence any portion of the thrust that is pointing out side the turn will oppose the horizontal component of lift. Note this same effect in a normally coordinated turn or slow flight adds to the lift vector.
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Salute again HiTech, I agree that the discussion is drifting off the issue, and will gladly 'kick in some corrective rudder' :)
If you believe a plane flying coordinated in a turn will turn more quickly right do to gyro torques , I will be happy to continue the discussion.
I can conditionally commit to that, as I'll explain later.
But these 2 questions are very very different then the statement a gyro makes your plane turn faster to the right. Which is the claim you made at the outset.
Actually in my OP I included a quote from Wikipedia or similar which made that claim. I was careful not to make that claim myself, although I still think it a possibility, provided we are careful to define the conditions. If a may refer back to this point later, as there is a more pressing matter:
1. A gyro does not produce a torque = to the torque applied to it in a 90 deg direction. It only applies a % of torque that is calculated by rpm * moment and mass of the entire object. I assume one you think about it, this should be obvious, because other wish even a mass spinning 1 1 rpm would produce a torque 90 degrees to the applied torque.
I think this may be the focal point of our problem. The resultant torque does indeed occur at 90 degrees to the applied torque at any rpm, that is a fundamental characteristic of the phenomena. If I can refer you to an extract from a magazine article on Seafires (you can find similar statements from other sources) :
"Any applied force which changes the axis position of a gyroscope causes the axis to move 90° to the applied force and in the direction of rotation"
ref http://www.auf.asn.au/magazine/seafires1.html#takeoff_swing
and from Wikipedia:
"If the speed of the rotation and the magnitude of the torque are constant the axis will describe a cone, its movement at any instant being at right angles to the direction of the torque."
and again from Wiki:
"If the rotating body is symmetrical and its motion unconstrained, and if the torque on the spin axis is at right angles to that axis, the axis of precession will be perpendicular to both the spin axis and torque axis."
ref http://en.wikipedia.org/wiki/Gyroscopic_precession#Torque-induced
In addition, and although I cannot find confirmation of this, the formulae seem to indicate that the output torque always = the input torque. I suspect that can only be true under 'normal' circumstances, as it doesn't seem right for instance, in the case of a small mass and a large input torque. It appears to be one of those Newtonian action=reaction things. But I'm definitely in over my head with the math at this level.
I've had my son check this (BEng & BSc Major in Pure Math) and he agrees, I say this only to make it clear that I've done about all I can to verify, I could still be in error. But the terms we have been using here (input torque and output torque) seem not to be in common use, rather just the term 'gyroscopic torque', which also suggests they are considered to be the same thing. In any event, the formulae should provide the correct output torque, but I would be interested to know if you are getting less output than input. Of course you could be referring to the gyroscopic effects as calculated on the engine in-situ, and so slightly forward of the centre of mass of the aircraft and therefore subject to torques at angles other than simple 90 degrees off the spin axis?
I hesitate to add more at this point due to the significance of this misunderstanding by one or the other of us (genuinely perplexed)
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I think this may be the focal point of our problem. The resultant torque does indeed occur at 90 degrees to the applied torque at any rpm, that is a fundamental characteristic of the phenomena. If I can refer you to an extract from a magazine article on Seafires (you can find similar statements from other sources) :
I agree the torque is always 90 degrees.
In addition, and although I cannot find confirmation of this, the formulae seem to indicate that the output torque always = the input torque. I suspect that can only be true under 'normal' circumstances, as it doesn't seem right for instance, in the case of a small mass and a large input torque. It appears to be one of those Newtonian action=reaction things. But I'm definitely in over my head with the math at this level.
As is obvious to you something spinning at a slow rate produces almost zero gyro effect I.E. torque 90.
I suspect that can only be true under 'normal' circumstances.
There is not any "NORMAL" circumstance with physics the equations are the same for any rate.
I believe you have answered you own question.
The problem lies in that we are not really speaking in and out torques but deal with a torque generates a 90 rotation rate. Or conversely in the case of a plane rotation rate generates a torque.
The key here is this line and equation in wiki .
http://en.wikipedia.org/wiki/Gyroscope
Under a constant torque of magnitude τ, the gyroscope's speed of precession ΩP is inversely proportional to L, the magnitude of its angular momentum:
This line simply is saying with more moment you get less 90 deg rotation rate for the same input torque.
Or conversely with more momentum you get more torque 90 deg up or down for the same turn rate.
But the problem we are speaking of stems from this statement of yours which I completely missed the real problem in 2 Places.
The first was in your original definitions.
4. The reactive torque is instantaneous to the initiating torque.
While this is a little correct it is very not exactly correct. Yes there is an instant reactive torque but that torque would be growing with time.
and this creates the error here.
You would know the figures whereas I can only suggest that the maximum torque applicable with the elevators would significantly exceed the maximum torque applicable with the rudder. As the gyroscopic effect produces a torque equal to the inducing torque but at 90 degrees to it, this suggests that in hard turns the rudder would in fact not be capable of correcting the induced yaw from the initiating action of the elevators.
The toque creates a 90 deg rate or a rate creates a 90 deg torque. But if my memory serves me, you will not find equations directly of torque to torque because the directions of the torque would have to be continually changing .
Think of it this way as you start the plane rotation you input a torque and the plane stares accelerating its rotation. This rotation is generating a torque 90 degrees. As the rotation speed increases the torque increases, but the assumption we are making is that the torque is corrected with controls and hence we are accelerating rotation in the same plane/axis.
And here is where I believe you are correct about how toque in = torque out. The rate of turn generates a 90 deg torque. When we add torque apposing this torque we are also adding a rotation rate via gyro opposite our current rotation rate. This then require a torque = to the 90 torque maintain the rotation rate of the turn.
Now I have not done the math on this piece so it could be incorrect but simply knowing how all net toques must be 0 (this is not debatable) in a stable turn I would think it is correct.
HiTech
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Camel:
Imagine welding/fixing a shaft to the inside of the drum of a 200 hp washing machine. The weight would be the same as of the camel's engine. The shaft is fixed to the aircraft on one side, and the back of the (rotating) washing machine is fixed to the airscrew. This is basically how it works.
Inline engines etc, - the whole mass of the engine is fixed to the aircraft, the shaft is pushed around by the pistons, and turning just the airscrew.
Is there no difference in the force that wants to throw your craft to the side? If it is and has been posted, I apologize, but would appreciate the point of correction.
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For a moment there I thought we might have found a solution :) But it seems we can agree on the physics both in terms of the aerodynamics and the gyroscopic effect. I can see that your knowledge of both undoubtably exceeds my own, so if there is any substance to my claims we must be close to resolving the issue. I hope so because I'm sure your time is valuable, and I think perhaps I have taken too much of it already. I do find it encouraging that we can engage in a discussion like this in good humour, and not take the outcome too seriously <Salute>
And here is where I believe you are correct about how toque in = torque out. The rate of turn generates a 90 deg torque. When we add torque apposing this torque we are also adding a rotation rate via gyro opposite our current rotation rate. This then require a torque = to the 90 torque maintain the rotation rate of the turn.
Now I have not done the math on this piece so it could be incorrect but simply knowing how all net toques must be 0 (this is not debatable) in a stable turn I would think it is correct.
HiTech
The presumption that we would correct the gyroscopic torque is only justified in a left turn (which is the reason we agreed that the left turn would incur an energy penalty). In the right hand turn following the right bank, we need only pitch up to induce sufficient right yaw for a co-ordinated turn (but here I presume enough gyroscopic effect to negate the usual requirement for right rudder).
Note that in this situation there is no pitch down, as the gyroscopic effect does not 'build' on itself. If it did, the result of the right yaw would be pitch down, the result of the pitch down would be left yaw, and we would be back where we started. This clearly does not occur so it seems we can avoid the pitch down, at least in theory.
So I think you will agree that given enough gyroscopic effect, to turn right we need only bank right and pitch up. And this is in fact the method outlined in the anecdotal evidence.
Several questions remain unanswered; and you have set me on a difficult path if I am to defend a premise which originated elsewhere. By this I refer to your challenge to prove that gyroscopic effect makes it possible to turn faster to the right in a co-ordinated turn. I have two issues with that, the first being that at no point did I make this claim (I did however provide several conditional quotes which indicated an unusually fast turn to the right, and I did say that the right turn would be significantly faster than the left).
The second issue is the constraint of co-ordination, as my understanding from the anecdotal evidence is that these turns were deliberately unco-ordinated, so that the effect on right yaw was allowed to go largely uncorrected (much like an aerial powerslide) or possibly that the rudder authority was not sufficient to fully correct it.
That said, I would certainly enjoy attempting to defend it, given the understanding that I am not certain at this time what the outcome will be. The conditions I mentioned in my previous post would be encapsulated in the following question:
(see next post, exceeded character limit lol)
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Could the Camel turn faster to the right due to gyroscopic effect than could be expected if it was fitted with a conventional engine of equivalent power and weight?
This is something that you could certainly test in simulation, provided the gyroscopic effect is modelled accurately (by simply switching it on and off while testing). So I will put down some ideas as a general outline of this new question:
As we all know in physics (Newtonian physics, Einstein opened a real can of worms beyond the scope of this debate) you can't get something for nothing. So any idea that the gyroscopic effect somehow 'powers' the turn seems invalid. For one thing, there is inertia in the spinning mass which must be overcome. I did some quick experiments with a gyroscope and obtained the following (admittedly rough) data:
Time to spin to a stop from an approximately equal rpm:
No applied torque, gyro spinning freely undisturbed - 3 mins 55 secs
Continual applied torque, gyro free to rotate under precession - 4 mins 05 secs
Continual applied torque, gyro prevented from rotating under precession - 1 min 45 secs
Given some margin for error we can see that by allowing the precession to occur unchecked the energy in the spinning mass dissipates normally, i.e. as when the gyro is undisturbed. But when the precession torque is corrected (the spinning mass prevented from precessing) the energy in the spinning mass dissipates much more rapidly.
This certainly has implications for our infamous left turn with all its' corrective measures (energy drain on engine) but more importantly it demonstrates that the energy to overcome any resistance to the resultant torque originates in the spinning mass, which clearly loses energy when the resultant torque meets resistance. So this is not 'something for nothing', but a valid 1:1 transfer of energy from one axis to another through the spinning mass.
If we now imagine an aircraft with poor rudder authority but more than sufficient elevator authority, equipped with a rotary engine such that a right hand turn might be attempted by simply banking right and pitching up, it seems possible that the resultant gyroscopic torque (right yaw) could indeed occur with more energy than by mere application of rudder, due to the transfer of energy from the 'strong' axis to the 'weak' axis via the gyroscopic effect. If we imagine that same aircraft to have most of its' mass located in very close proximity to the C of G, and consider the effects on the turn of that design in addition to the gyroscopic effect, we can begin to imagine how rapidly this aircraft might turn to the right. No doubt you possess the data on maximum pitch and yaw torques for the Camel, so you can probably evaluate this theory easily.
If that same aircraft was fitted instead with a conventional engine, the entire mass concentration around the C of G would need to be changed due to the unique compact design of the rotary engine. This makes any comparison of turning with and without gyroscopic effect difficult, but still possible by flight testing in simulation.
So in answer to this new question, I would say 'yes' for the following reasons:
1. If the Camel had been fitted with a conventional engine, the entire design would have been different and would be unlikely to turn as rapidly or tightly.
2. If a conventional engine of equal size and power had been available, poor rudder authority would have resulted in a less rapid right turn (and yet a more rapid left turn).
Therefore a conditional 'yes', because at the time there was no other way to achieve this turn rate other than with gyroscopic effect from a small engine situated close to the C of G. The designers at the Sopwith plant seem to have designed the aircraft specifically for this ability following on from their experience with the Pup. The Fokker Dr1 may very well have been an attempt to produce an aircraft of similar performance, but I believe the attempt failed for a number of reasons, not least of which that the Dr1 failed to make as effective use of the gyroscopic effect due to less spinning mass, mass distribution and less power.
HiTech, you clearly want to model flight accurately and just as clearly have the necessary knowledge and skills to achieve the best possible outcome. But models are models and there are bound to be limitations. For instance, I have an old gliding habit of coming in too high on finals (better high than low deadstick lol) and sideslipping to wash off the extra alt, but I have not been able to find a simulation which allows me to do this (other than RoF, which has other issues I can not live with). Anyone following me in must think I am drunk (often true lol) or a terrible pilot (hopefully not entirely true) as I stubbornly swing from one side to the other while the FM modifies the slip and forces me off track. I heave on the stick and kick hard on the rudder in the forlorn hope that your zero torque sum will come to my aid but alas, I can only enjoy the sensation briefly before the rudder authority fails and I end up being forced to swing it across the other way.
So I think you would agree with me that while the highest level of authenticity is sought, there must always be shortcomings. The goal in the end is surely entertainment, and I doubt you would recommend that someone with high hours on an AH Mustang for instance should climb into the cockpit of a P51 at the next airshow and strut their stuff. So if entertainment is a key factor, perhaps I could suggest that issues such as this might be dealt with in less clinical fashion. What has developed in this instance into a rather cold scientific debate might instead be approached from the point of view where historical evidence carries as much weight as raw data. Just a few thoughts, and I've probably drifted off topic (apologies).
Certainly neither of us has flown either a Camel or a Dr1 (and I for one hope never to do so lol). Therefore I think we must look closely at the science, but also make use of whatever evidence we can obtain from historical notes, flying models and the very few replica aircraft still flying. I've contacted the warden of one such aircraft but as yet had no reply.
I do know my campfire etiquette, and bringing a tin of beans to your fire does not give me the right to mess with it. I can enjoy its' warmth and if invited maybe poke it with a stick, but I must always fart downwind and never pee on it. So thanks for being both patient and helpful, I trust my enquiries were not too much of a nuisance. I merely hoped to make a suggestion in the first instance, and perhaps a small positive contribution in the second.
Again conforming to good etiquette, I think you should have the last word (answers to any questions notwithstanding).
Salute
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1st I am still not sure this statement of mine is correct.
nd here is where I believe you are correct about how toque in = torque out. The rate of turn generates a 90 deg torque. When we add torque apposing this torque we are also adding a rotation rate via gyro opposite our current rotation rate. This then require a torque = to the 90 torque maintain the rotation rate of the turn.
Anyone other physics guys out there know if this is correct of not?
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I can not see why leaving a plane in uncoordinated flight would be of any use. Either way the torque has to be stopped, only you are doing it more with fuselage then with rudder, which would create more drag then using rudder and hence slow the turn.
n very close proximity to the C of G, and consider the effects on the turn of that design in addition to the gyroscopic effect, we can begin to imagine how rapidly this aircraft might turn to the right.
Why would the distance an engine is away from the CG have any effect on turn rates? Remember a turn is a translational movement not rotational , hence it is not effected by moments. And once the plane is rotating at the turn rate it requires no additional torque to maintain the turn. A shorter plane I.E. shorter tail moments would then require more force to offset the gyro and hence more drag.
1. If the Camel had been fitted with a conventional engine, the entire design would have been different and would be unlikely to turn as rapidly or tightly.
2. If a conventional engine of equal size and power had been available, poor rudder authority would have resulted in a less rapid right turn (and yet a more rapid left turn).
These are 2 strange case, how about we fit the camel with the same HP and weight engine, but a conventional turning prop, I.E. less moment. Would it turn better or worse in a right turn. I would think less.
No applied torque, gyro spinning freely undisturbed - 3 mins 55 secs
Continual applied torque, gyro free to rotate under precession - 4 mins 05 secs
Continual applied torque, gyro prevented from rotating under precession - 1 min 45 secs
I would think this is almost all do to friction, but really this is a very minor force . It appears a large difference but off the top of my head you are looking at less then 1% of the power produced by the engine.And then you are taking the difference of 1% or 0.5% of the power. An easy way to think of it is how much energy did you put into the system to make the gyro spin. It took maby 1.5 secs to pull the string.
So now what percentage of that pull would it take to maintain the RPM of the gyro given your above numbers?
But models are models and there are bound to be limitations. For instance, I have an old gliding habit of coming in too high on finals (better high than low deadstick lol) and sideslipping to wash off the extra alt, but I have not been able to find a simulation which allows me to do this (other than RoF, which has other issues I can not live with). Anyone following me in must think I am drunk (often true lol) or a terrible pilot (hopefully not entirely true) as I stubbornly swing from one side to the other while the FM modifies the slip and forces me off track. I heave on the stick and kick hard on the rudder in the forlorn hope that your zero torque sum will come to my aid but alas, I can only enjoy the sensation briefly before the rudder authority fails and I end up being forced to swing it across the other way.
You have me completely confused a slip would be left rudder forward stick and right aileron and the plane continues in a straight ahead path, just with more drag.Your description seems to be back stick.Slips are one of the most common hot landing maneuvers used in AH. And why you would run out of rudder authority In a slip I have no idea.
And finally if you are going to analyze which way a turn would be faster, you can not just analyze the gryo forces. You must also look at other components that can create an asymmetrical turn such as slip stream ,Pfactor, engine angle offsets. And this is why I said I have no desire to have that discussion because the level of precision needed for that discussion is far out side the realm of the bbs.
HiTech
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I am still reviewing my understanding of the math behind various gyro torques, but I did find a very helpful website to do the math.
http://www.gyroscopes.org/math.asp (http://www.gyroscopes.org/math.asp)
So far the calculations at this website correlate to the examples in my Physics text book. So I am reasonably comfortable that the website is mathematically accurate. For me the calculation I am most interested in is at the bottom and refereed to as "reaction couple".
<S> Baumer
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Its all very interesting but lets talk about the REAL freak of the bunch. That darned Dr1. What the heck is that manoever where it stalls sideways and then snap recovers in the reverse direction. It's as if there is no fuselage to provide drag....it reminds me of a box kite falling sideways that suddenly reverses direction. Very odd to be fighting one of these Dr1 when it pulls that move....some folks have gotten scarey good using that move.
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To me this issue applies to both aircraft, not just the Camel. Now I can understand it having different implications based on other aerodynamic factors between the two (F.1 and Dr.1) but I think the gyroscopic forces (torques) need to be understood better by everyone. Or in my case, I would like to look at them and understand how it applies mathematically to an aircraft no matter what model it is.
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Howdy Baumer.
I am still reviewing my understanding of the math behind various gyro torques, but I did find a very helpful website to do the math.
http://www.gyroscopes.org/math.asp (http://www.gyroscopes.org/math.asp)
So far the calculations at this website correlate to the examples in my Physics text book. So I am reasonably comfortable that the website is mathematically accurate. For me the calculation I am most interested in is at the bottom and refereed to as "reaction couple".
<S> Baumer
I assume you realize the reaction couple is just stating a torque is create 90 deg to a rotation velocity? I.E. the basic thing that makes a level circle move you nose up or down?
The computation of that force is really quite simple and I assume you already understand the equations posted on that page, amazingly the force couple equation exactly match AH'.
So what are you interested in?
HiTech
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is it safe to say that a spinning engine from ww1 is in fact a force field generator similar to what was used on Tie Fighters?
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The part I still don't understand properly is how long that torque is present. I think that reaction couple torque is present as long as the nose of the plane is turning along the horizon (assuming a coordinated turn), is that correct?
Also since the roll axis is aligned with the engines axis (gyro axis) rolling in to the turn, dose not change the vector of the reaction couple torque (again assuming a flat coordinated turn). Is this last statement correct?
And one last statement just to make sure I understand this properly.
In the last data fields the "distance between bearings" that would be the distance from the center of mass of the engine, to the center of gravity, correct?
Thanks for taking the time to help me understand the physics better HiTech.
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The part I still don't understand properly is how long that torque is present. I think that reaction couple torque is present as long as the nose of the plane is turning along the horizon (assuming a coordinated turn), is that correct?
As long as the plane is turning (technically the rotation part of the turn , not the translation piece, I.E. the plane could be standing still) it will be generating the torque.
2nd. Assuming you are turning a flat circle. I.E. parallel with the ground. The torque will always be up or down relative to the GROUND depending on turn direction.
[/quote]
Also since the roll axis is aligned with the engines axis (gyro axis) rolling in to the turn, dose not change the vector of the reaction couple torque (again assuming a flat coordinated turn). Is this last statement correct?
It does not change the direction relative to the world / circle, but it does change the direction relative to the plane as it rolls. I.E in a 45deg left bank turn the torque will be on a 45deg line between your right wing and rudder. I.E. some pitch, some yaw.
And one last statement just to make sure I understand this properly.
In the last data fields the "distance between bearings" that would be the distance from the center of mass of the engine, to the center of gravity, correct?
[/quote]
Yes, that part is simply translating a torque which is defined as 2 opposing forces each 1 ft apart (when using ft/lb as torque unit) to a force with a different moment arm as you know Torque = force * distance.
Thanks for taking the time to help me understand the physics better.
The pleasure is mine, I love thinking about this stuff from different perspectives.
HiTech.
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HiTech,
I've been reading as much as I can find on the Internet about the F1. No one gives any specifics about the effect of the rotary engines torqe other than anecdotally and the statement of legend, "gyroscopic effect". No physics explanations as far as I can find. But, a common theme is the specific results the designer wanted to achieve. The engine, pilot, guns and fuel tank all cramed into the first 7ft of the airframe. The tail heavyness. The propensity to suddenly stall or spin if forward speed was not maintained. Specificly a strong nose high climb to the left or a nose down turn to the right.
This almost makes me wonder if the 270dgr left hand turn by turning right was really taking advantage of the right hand nose down tendancy to snap the plane down right and recover around to the left. After all one of the things that killed many pilots was its rapid stall and spin.
After all of your research to create the F1 in AH, what is your personal take on the planes design and how the design would allow skilled pilots to trade nose for tail to the right or seem to turn faster to the left by performing a right hand manuver?
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bustr: I have no idea of the story you are speaking of. I'm the physics guy, pyro is the history guy.
HiTech
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Derned if I could find any physics discussions to explain the rotary engines 270dgr right turn in the F1 other than the aircraft was designed to rapidly stall and spin on purpose to the right. All references point out the extreme departure from the previous rotary engined Triplane and Pup's solid stability to a purpose driven design that was unstable. Why didn't the Pup, Triplane, or even Dr1 have the magical gyroscopic effect in some degree? If you look at the wing area for the Triplane and F1 they are equal with similar engine horse power.
F1 - 231 ft\sq....130hp rotary
Tri - 231 ft\sq....130hp rotary
Pup - 254 ft\sq....80hp rotary
Dr1 - 201 ft\sq...100hp rotary
Makes me consider that skilled pilots learned to take advantage of making it spin out of control to the right in a nose down attitude. You have modeled how quickly the F1 stalls based on the reading I've done around the internet. I have yet to find any pilot comments from the era specific to "x,y,z here is how you use the F1's purpose designed instabilities" to make impossible looking turns to the right so as to turn inside of the Hun. Is it possible the genius of the Camel is not the gyroscopic effect from the engine but the specific design instabilities to make use of what was known about torqe at the time?
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As indicated I'm happy to answer specific questions but feel I've had my time on the 'soapbox', so I'll attempt to reply without adding any further argument if possible. I found only two direct questions (the others were I think rhetorical) so here goes, if I need to elaborate it is only in the interests of clarity:
Why would the distance an engine is away from the CG have any effect on turn rates?
In a balanced turn, none. But the whole premise of the Camels' rapid right turn is based on the idea of a skidding gyroscopic turn. e.g. If you imagine an aircraft suddenly rotated 90 degrees to the right yet which somehow maintains its' attitude and structural integrity (there are all kinds of issues with this, but bear with me) then at some point (after some altitude loss) thrust will regain authority, the aircraft will regain flying speed and continue at 90 degrees to the original direction. Clearly this is an extreme case with any number of failure issues but somewhere between this example and a co-ordinated turn there exists a workable skidding turn, with effectiveness and extent determined by aircraft design and pilot skill. No doubt the entry speed would be high so that loss of airspeed over the inside wing would not cause a stalled condition, and the angle of bank probably about 30 degrees. In the Camel (and to a lesser extent in other rotary engine aircraft) the torque required to rotate the aircraft rapidly was provided by the gyroscopic effect induced by a powerful and rapid pitch torque working on a spinning mass which was close to the C of G, which as you know would allow the aircraft to rotate (yaw) more rapidly than if the engine had been further from the C of G.
The amount of skid which could take place while maintaining control is dependent on more factors than I would care to resolve, but providing the airframe maintained integrity and the pilot avoided the spin, the Camel should have been capable of changing direction more rapidly than any other aircraft of the time. I have seen a Pitts Special performing a similar manoeuvre, but that was likely done mainly with rudder, whereas the Camel had relatively poor rudder authority and was reliant on gyroscopic effect transferred from the pitch axis for the rapid rotation.
So now what percentage of that pull would it take to maintain the RPM of the gyro given your above numbers?
I included the test results mainly to demonstrate that the energy for any work done came from a valid source. Like yourself I doubt that the drain on the engine would be particularly significant to the debate. The data was obtained by rapidly and repeatedly applying torque of unknown value so as a means of determining specific energy loss data it was less than useful.
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I am an idiot :old:. Sorry to break my own rules regarding only answering questions but I thought you wouldn't mind reading that.
I've allowed my loathing of the Dr1 to obscure something important; just tried the manoeuvre in the Tripe and achieved a full 360 degree turn in about 6 seconds, abit messy but the Dr1 isn't my usual mount. I'm sure someone with appropriate experience can do better. So the effect is there, and it works, but appears not to be achievable with the Camel.
Its all very interesting but lets talk about the REAL freak of the bunch. That darned Dr1. What the heck is that manoever where it stalls sideways and then snap recovers in the reverse direction. It's as if there is no fuselage to provide drag....it reminds me of a box kite falling sideways that suddenly reverses direction. Very odd to be fighting one of these Dr1 when it pulls that move....some folks have gotten scarey good using that move.
Thanks Yeager, you put your finger right on the problem <Salute>
This requires a change of perspective.
First it seems that HiTechs' gyro model is alive and well (which explains your astonishment HiTech <Salute> hehe).
Second and unless I'm particularly clumsy (or have very poor controls/control setup) the Camel isn't quite set up right for the effect. Probably something to do with lift coefficient, not my forte, a minor tweak perhaps? Anyway I can't master it, but the Dr1 seems fairly well behaved through the turn with a gentle touch.
To fly the manoeuvre try 110mph, right bank approx 30 degrees with initial right rudder to commence the turn and gentle pitch up. Move quickly to left rudder (lots to max) and continue pitch up but not so much as to overly rattle the stall horn. Try to maintain 30 degree bank throughout, if it gets away from you it accelerates rapidly to inverted.
I have to ask, with so many Dr1 pilots about, why didn't someone speak up about this? Sneaky little monkeys :joystick:
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After further flight testing I think there's a better picture emerging; earlier in the discussion we spoke about sustainability, with reference to immediate rotation vs translation. I couldn't see any reason why the gyro effect would improve one and not the other, so the proposed turn was referred to as 'sustainable', but that may have confused the issue somewhat. It certainly appears that the rotation into the turn and the turn itself are more rapid, but it looks like there's an energy penalty. It may be that the manoeuvre was either used sparingly (i.e. direction reversal) or if sustained perhaps only while diving. Horizontal reversals in the Dr1 seem to take about 3 seconds, holding the turn for 360 degrees is actually quite tricky and bleeds alot of E. There is definitely an impressive and rapid right yaw response to the pitch up, but I think the term 'sustainable' does not apply in the sense that the turn can be sustained for more than a few seconds (unless diving).
It seems likely that WW1 combat was generally less a matter of circling and more a hit and run affair, there must have been fights where they chased tails for awhile but it seems a dangerous tactic in a crowded sky. This might be the reason a non-sustainable rapid turn was so valued, as the combatants might never have attempted to sustain it even if it were possible. So it seems quite likely the Dr1 should out turn the Camel in a sustained co-ordinated turn, whereas (and this has yet to be proved) the Camel earned a reputation of being able to out turn any other aircraft based entirely on this non-sustainable rapid reversal under gyroscopic effect.
With my stick setup the Camel gives a little of this but prefers to stall the inside wing than yaw to the right. Any thoughts, or different results?
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Tusk, truly I am sorry for your pain sir. But us Dr1 pilots were just enjoying the barbecue to much to want to step in and spoil it. Besides, some did make comments, to whit Baumer, etc. To which you initially were not very open an excepting of.
So since you were on a crusade, we more or less thought we'd sit back and see how far you got.
Actually you did fairly well on the whole. <S>
Besides, the physics discussions were fascinating. Also most of us Dr1 knuckle dragger types can see when we are outclassed in a fight. So we let you guys play with the big words and the equations. I mean obviously this was one of those situations where it would be entirely too easy to say something which seemed simple. But which would leave everyone else pointing fingers and snickering. Much wiser to sit back, nod your head at the appropriate time, nudge your neighbor "did you get that?" and every now and then let out an long "oooaaaaaaaaaaaaahhhhhhhhhhhhh hh" so that is how it works."
Truly I feel your pain, nasty stuff that righteous indignation, it can get you into all kinds of trouble.
Pull up a chair, grab a beer, I'm not sure its done yet. They'll be serving brisket or roasted flaming newb in geek sauce before the evening is over.
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lol Ghosth, thanks for the sympathy but really I have survived the roasting more or less unscathed :aok
The debate encouraged me to think through the science of the famous turn, and understand better the true nature of it. Even if my original request is not fulfilled, I'm happy to have shaken the theory out and got to the heart of the matter in the face of some extraordinary (and intelligent) opposition. The debate will no doubt continue as to whether the Camel could in fact out-turn the Dr1 but I am satisfied, having found nothing in the detail that contradicts the legend, in fact more support for it.
As for my oversight of the DR1s' fast turn in the sim, with an average 270ms ping and occassional packet loss I see some weird stuff, and hadn't given much thought to the sight of DR1's sometimes doing rapid turns (in fact I've seen F2b's and DVII's doing it, almost certainly due to my connection), and I generally do not fly the thing. There is no evidence that I have seen to suggest the Dr1 could actually perform the manoeuvre, so I had no real reason to try it.
In your first post in this thread you said "Your just not seeing the big super advantage that you thought you'd see." That was entirely correct. There's a huge amount of supporting evidence but I was made quickly aware that the rules of the discussion allowed only hard data and logic. As everyone suspected, there is very little if any hard data on the manoeuvre. And so with HiTech to keep me on the straight and narrow, we thrashed out the logic and now I can ask for the same thing I asked for in my OP:
"just a bit more of that legendary torque induced right turn capability"
Of course, I always appreciate the encouragement of those like yourself <S>
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lol Ghosth, thanks for the sympathy but really I have survived the roasting more or less unscathed :aok
The debate encouraged me to think through the science of the famous turn, and understand better the true nature of it. Even if my original request is not fulfilled, I'm happy to have shaken the theory out and got to the heart of the matter in the face of some extraordinary (and intelligent) opposition. The debate will no doubt continue as to whether the Camel could in fact out-turn the Dr1 but I am satisfied, having found nothing in the detail that contradicts the legend, in fact more support for it.
As for my oversight of the DR1s' fast turn in the sim, with an average 270ms ping and occassional packet loss I see some weird stuff, and hadn't given much thought to the sight of DR1's sometimes doing rapid turns (in fact I've seen F2b's and DVII's doing it, almost certainly due to my connection), and I generally do not fly the thing. There is no evidence that I have seen to suggest the Dr1 could actually perform the manoeuvre, so I had no real reason to try it.
In your first post in this thread you said "Your just not seeing the big super advantage that you thought you'd see." That was entirely correct. There's a huge amount of supporting evidence but I was made quickly aware that the rules of the discussion allowed only hard data and logic. As everyone suspected, there is very little if any hard data on the manoeuvre. And so with HiTech to keep me on the straight and narrow, we thrashed out the logic and now I can ask for the same thing I asked for in my OP:
"just a bit more of that legendary torque induced right turn capability"
Of course, I always appreciate the encouragement of those like yourself <S>
Unlike so many on this bbs, you did a rare case of following the rule of holes, and acctully filled it back up.
<salute>
P.S. glad you think the physics of gyros are hashed out,I still have 1 problem with energy and force conservation in my head in the analysis, If I figure it out I let you know, but it doesn't effect our modeling which would automatically have the correct result.
HiTech
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Derned if I could find any physics discussions to explain the rotary engines 270dgr right turn in the F1 other than the aircraft was designed to rapidly stall and spin on purpose to the right. All references point out the extreme departure from the previous rotary engined Triplane and Pup's solid stability to a purpose driven design that was unstable. Why didn't the Pup, Triplane, or even Dr1 have the magical gyroscopic effect in some degree? If you look at the wing area for the Triplane and F1 they are equal with similar engine horse power.
F1 - 231 ft\sq....130hp rotary
Tri - 231 ft\sq....130hp rotary
Pup - 254 ft\sq....80hp rotary
Dr1 - 201 ft\sq...100hp rotary
Makes me consider that skilled pilots learned to take advantage of making it spin out of control to the right in a nose down attitude. You have modeled how quickly the F1 stalls based on the reading I've done around the internet. I have yet to find any pilot comments from the era specific to "x,y,z here is how you use the F1's purpose designed instabilities" to make impossible looking turns to the right so as to turn inside of the Hun. Is it possible the genius of the Camel is not the gyroscopic effect from the engine but the specific design instabilities to make use of what was known about torqe at the time?
Bustr when you compare the F1 and Dr1 keep in mind that the aspect ratio of the wings is different. Even with the same wingloading and power the Dr1 should have less induced drag which would give it a better sustained turn than the F1. The F1 should have a higher max AOA and a slower stall speed.
The "right turn to go left" and turn better is interesting because even if you ignore gyro effects you can gain angles with a lag displacement roll, which is simply the "turn right to go left" maneuver popularized by Boyd.
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From the internet the few stories you find about the Snipe's combat success come down to it's climb and manuverability. But, not a gyroscopic effect by its 230hp rotary engine.
Snipe - 230hp rotary....274ft/sq area
Camel - 130hp rotary...231ft/sq area
The Snipe was designed as the predisessor to the Camel and purpose designed to be stable while taking advantage of a more powerful rotary engine via rate of climb and manuverability at altitiude. The Camel was purpose designed to be unstable to give pilots a rapid erratic manuver to the right hand that the german planes were too stable to easily duplicate. Why design an airplane with all the weight in the nose, is tail heavy, and stalls by looking at it wrong after you have designed two successfull highly manuverable predicessors the Triplane and the Pup?
The F1 in the game will stall rapidly and flys with a tail heavy attitiude per real world flight descriptions. You can pull it nose up and rapidly stall it and the engine\prop torqe will help pull you down to the right sort of. In game it has a bad tendancy to just float tail down and crash unless you kick right rudder before loosing control authority. In level flight you can rapidly snap it down to the right and in the process while nose down your canopy will rotate 270dgr clockwise. Then as you pull up completing a 270dgr right hand turn to the left.
Because we tend to furball and mow the grass in the WWI arena at the same time rather than meet at historic altitiudes. I suspect we are not able to get the most from our F1 because many spend their time plowing furrows with it due to its purpose designed instabilities.
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For those who are interested, this thread at The Aerodrome about the Camel seems legitament.
http://www.theaerodrome.com/forum/2000/9166-sopwith-camel-facts.html
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Anybody already posted this?
http://www.youtube.com/watch?v=Ch7Z4UurPSk
Interesting part is in 1:30 when the scientist tries to pull the axle down only to get a momentum shift of 90 degrees and the centrifugal rotator resists the force and starts to turn right instead.
Of course it cannot be that pronounced in an aircraft but it still gives an illustrative example.
-C+
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you did a rare case of following the rule of holes, and acctully filled it back up.
<salute>
Does the rule of holes apply to the above quote?
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After all the internet research about the F1 and experience with it in the WWI Arena, I understand why that arena has devolved into a Dr1 Mosh Pit with the small number of dedicated players. I hope HiTech has plans to release another round of four aircraft soon to liven things up.
By the way, after reading more about Precession, wouldn't there be an unstable configuration of CG, wing area and rudder control surface area that would allow the rotary engine's gyroscopic precession to augment the purpose designed instability? If you pick up a spinning 10kg gyroscope by one end, precession will make it appear to be a 5kg weight as long as you follow the direction the gyroscope wants to travel. Did the rotary engine in the F1 produce enough precession effect to matter in its manuvering?
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I have made an effort to try and master the Dr1, or at least fly it more. It still behaves oddly for me. I'm not a test pilot and I genuinely don't know the science of flight but I do have a good number of hours in damned near every type in "this" game and I know how these FMs tend to "behave and feel". There are times where I genuinely get the feeling that I am not flying the Dr1, but floating it at odd angles often in contrast with gravity. I cant really officially complain about it because for all I know that's the way the Dr1 actually performed. Still, it does not bode well for my own personal plausible believability that I am participating in a air combat simulator. I tend to look at Dr1s with a measurable amount of contempt.
Something feels wrong about them with me I have nothing to base it on. It is frustrating, but I temper it with a real love for the game and I will continue to persevere in the face of adversity :joystick:
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Yeager the Dr1 is less stable than the Camel so the Gyro effect is more noticeable.
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Understood. I enjoy the F1 quite a bit. Perhaps I should master that one before putting alot of time into the Dr1.
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(http://img.photobucket.com/albums/v51/shortsnorter/camelinflight.jpg)