Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: F4UDOA on September 29, 2003, 01:50:32 PM
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Heya's,
I am a reader of flight manuals for various WW2 A/C. One piece of information that is in many but not all flight manuals is the minimum reccomended speed for performing maneuvers.
For instance in the Spitfire IX manual it says that for looping the entry speed should be 260knots or 300MPHIAS.
In the Tempest Manual it list the minimum reccomended speed for entering a loop as 324knots or 350MPH IAS.
In the F4U-1 manual it show the minimum reccomended entry speed for inexperianced pilots at 280knots or 320MPH IAS.
This shows me a couple of things.
1. In AH we can perform virtical maneuvers to easily.
2. The disparity in maneuverability between the Spit IX, F4U-1 and Tempest V.
My questions are these.
Is the differance in manuverability between different A/C represented in AH?
Are we looping to easily?
All speeds listed are IAS so altitude should not play a part.
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Hi F4UDOA,
>Are we looping to easily?
Well, the above speeds are probably meant as guidelines on how to perform good-looking loops without undue strain to pilot, engine or airframe and low probability of spinning out on the top.
An all-out vertical combat manoeuvre might look dicedly different.
I once did an analysis for the Fw 190A-8 (for which pretty good data is available), and I concluded that at sea level and with 50% fuel, it should be able to loop continuously and even gain a bit of energy with each loop.
The "continuous looping" discussion was big on this board a while back, but I honestly don't know how the Aces High Fw 190A-8 compares to that.
It could be that due to some error in my math, I'm wrong about it anyway :-)
However, there should be no doubt that vertical manoeuvres indeed are more energy efficient than horizontal manoeuvres for the same results.
Regards,
Henning (HoHun)
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Well I must say the go to easy yes, in all other flight sims you aren't able to make them fast rolls/loops etc. Maybe it's because Aces High has a very 'fly-friendly' or easy flight engine
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HoHun,
Don't misunderstand me. I have no problem with the energy retention part of AH. In fact I was one of the people back in 1.03 that wanted better E-retention and I believe the E-retention we have is fine.
In fact I have read articals on pilots doing just what you describe. Effortless repeated rolls.
However the minimum looping speeds while not being hard numbers are not too far off I would believe. Is there anyway to determine what the minimum looping speed would be for a given A/C?
Frank3,
I am not a huge believer in to much roll internia for single engine fighters. I think the WB3 FM is way way off and wouldn't want to see it here.
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Originally posted by F4UDOA
minimum reccomended speed for entering a loop
The point is to know what factors determine the term "minimum" in that sentence. In any case, with a 50% fuel SpitIX you can perform a perfect loop (no stall horn at all) starting at 180mph just after take off, probably even slower.
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Mandoble,
I know you can. That is why I ask the question. Is this right?
The other part of this is the relative parody in the ability to loop at low speed for all A/C. The Tempest should not maneuver as well as it does relative to other A/C based on the flight manual data.
I have made this point before on flat turning circles as well.
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Originally posted by F4UDOA
In fact I was one of the people back in 1.03 that wanted better E-retention and I believe the E-retention we have is fine.
What was that fix that affected so noticeabily every light wingloaded plane? We had a N1K2 and after the 1.04 we had a monster.
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Originally posted by MANDOBLE
What was that fix that affected so noticeabily every light wingloaded plane? We had a N1K2 and after the 1.04 we had a monster.
Yeah. Sure.
Basically if pre 1.04 was correct there is now way that a A6M or Spitfire ever would have been seen as anything other than a joke. They never would have been accepted for service. The Japanese and Italians would never have been fixated on close fighting manuverability either.
1.04 fixed that.
It is your problem that you can't wrap your mind around it. You are too fixated on the "Uber Luftwaffe and their uber machines" to give a fair shake to anything else.
F4UDOA,
I'd those minimums would be applicable to normal flight, not combat flight. They are saftey tips, not performance limitations. I doubt they are anywhere near the margin of failure for those aircraft.
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Hi F4UDOA,
>However the minimum looping speeds while not being hard numbers are not too far off I would believe. Is there anyway to determine what the minimum looping speed would be for a given A/C?
If you have a lot of information about a certain plane, it can be done.
However, with that amount of information, you could probably answer any other question without needing to know the loop entry speed first :-)
If you read the pilot's notes for the Spitfire II, you can see the following description:
000° - 300 mph IAS
090° - 200 mph IAS
180° - 115 mph IAS
360° - 290 mph IAS
Assuming the loops terminates at the initial height, that's a loop that loses some energy. It also is a loop with a large margin for error as the 1 G stall speed of the Spitfire II is 79 mph IAS. That means that the Spitfire can still pull 2.1 G while going over the top. (It's probably necessary to keep some positive Gs over the top to avoid starving the carburettor.)
How much of a safety margin that is can be appreciated by considering that to get over the top with the least energy required, you'd unload the airplane and float around at 0 G. That's possible at virtually no forward speed - you'd not fly a circular loop, though, but a narrow egg.
The carburettor example shows the type of additional consideration entering the recommendations from the Pilot's Notes. It might be that carburettor or oil supply dominate the picture, or control authority to counteract engine torque. Maybe the author of the Pilot's Notes even has enough freedom to recommend a speed he personally considers safe so that criteria are different from plane to plane.
I'd be very hesitant to conclude anything about the relative manoeuvrability from such figures.
They certainly tell us something about the minimum capabilities of an aircraft, though :-)
Regards,
Henning (HoHun)
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Originally posted by Karnak
Basically if pre 1.04 was correct there is now way that a A6M or Spitfire ever would have been seen as anything other than a joke. They never would have been accepted for service. The Japanese and Italians would never have been fixated on close fighting manuverability either.
I can understand u were unable to fight in those rides, but your problem was not common:
Tour 1 stats:
The Spitfire Mk IX has 23247 kills and has been killed 23596 times.
The C.205 has 8706 kills and has been killed 8767 times.
The N1K2 has 13637 kills and has been killed 11857 times.
(we had no zeke at these times).
Zeke was introduced in tour 5:
The A6M5b has 2476 kills and has been killed 3463 times.
And today:
The A6M5b has 7620 kills and has been killed 10067 times.
Very similar than present tours.
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The first time I saw a Spit IX, it took off in less than 200 yds and went straight into a loop while raising the gear.
Spit I would be able to loop2 times with no problem, 3 times in the hands of an expert.
So, regarding the Spits in this sense, they may be undermodelled in AH :D
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I recently saw a video of an airshow pilot flying a P51D and a SpitfireIX as well as a great corsair run.
The thing is it showed the pilots performing various manouvers like loops etc from inside the cockpit and the one thing i noticed was the ease with which these planes performed the loops. It had none of the mushy look you sometimes get with AH.The pilot hardly seemed to move and certainly didnt look like he was straining in any way or being exposed to negative G.It just appeared so much easier for these planes to loop. The speeds seemed to stay fast too, none of this heavy slowing down at the top of the loops which is often the case in AH I find.
The corsair especially seemed to have power in abundance.It just powered its way all the way around.
Also when i saw them all at the Duxford airshow they seemed to be performing their ACMs with ease.To me it seemed they had a lot more power than i feel i have in AH. Still the problem is that AH is a model of everything like the ground etc and although mathmatically it may well be highly accurate the graphics for the ground etc might make it all appear different.ground rush and the lack of features with which to judge speed against and the fact it cant be photo realistic to look at must play a major part.
However if it does seem we should be able to loop more easily then im all for corrections. F4UDOA you had better get on the case with your lawyer like research right away!! :D
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Originally posted by MANDOBLE
I can understand u were unable to fight in those rides, but your problem was not common:
Tour 1 stats:
The Spitfire Mk IX has 23247 kills and has been killed 23596 times.
The C.205 has 8706 kills and has been killed 8767 times.
The N1K2 has 13637 kills and has been killed 11857 times.
(we had no zeke at these times).
Zeke was introduced in tour 5:
The A6M5b has 2476 kills and has been killed 3463 times.
And today:
The A6M5b has 7620 kills and has been killed 10067 times.
Very similar than present tours.
If you are trying to paint a picture of an AC's effectiveness using those numbers, they are already flawed. Statistically, your sample is much bigger for the more recent set.
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Originally posted by F4UDOA
Frank3,
I am not a huge believer in to much roll internia for single engine fighters. I think the WB3 FM is way way off and wouldn't want to see it here.
Please stop calling me frank3!!! it's just Frank!
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It is your problem that you can't wrap your mind around it. You are too fixated on the "Uber Luftwaffe and their uber machines" to give a fair shake to anything else.
Karnak,
You are saying that I am fixated on Luftwaffa A/C? Not hardly, I have much more issue with Russian and Allied A/C performance that is out of wack. The La-7, NIK2, Spit V, IX and XIV especially in the area of fuel consumption. I am satisfied with the 109G10 now that I have real data.
The issue I am most interested in is relative maneuverability of different A/C and their individual characteristics.
I have always felt that the stall speeds of most AH FM's fell to close together. The reccomended looping speed is a great example. Yes the Spit will win a looping contest with the F4U, but will the F4U win the contest with the Tempest? Maybe but not by the same margin as defined in the flight manual. The Spit IX is 20MPH superior in it's minimum entry speed to the F4U. But the F4U is 30MPH superior to the Tempest and Typhoon.
My question is how is this reflected in AH?
Hazed,
I know what you mean, I have interviews with modern pilots that say the same things about the ease of looping and maneuvers. It really shows the relative lack of experiance of most WW2 pilots.
I was at an Airshow a couple years ago where it was a cloudy day with a low ceiling. They were going to fly a P-51D, P-47D, F4U-1D and P-40. I spoke to the pilot (Dan Demeo I think his name was) he told me that they could not fly the P-51 or P-47 because of the low clouds and the minumum altitude required to loop those planes or do virtical maneuvers. The F4U and P-40 had no such problem.
I actually listen to the AFDU data where is says that X plane should be able to get on the tail of Y plane in 3 turn etc. When this does not work I try the math. If the math agrees then I try AH and If AH does not agree then I try the message boards.
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yep F4UDOA , and i think you should be allowed to question anything you find, regardless if you have got the wrong idea and are mistaken or if you have discovered a flaw.
The BB is after all a forum for debate.Without being able to ask for help understanding things I fail to see its true purpose.
If people happen to focus on one particular aircraft it doesnt mean they are closed to all others, just they gather info more pertinant to their favourite type and thus miss out on the wider picture.I for one have read these boards and then followed up what ive read by buying books and watching programmes that explain the subject matter.It a hell of a lot of fun and i would consider it almost a seperate hobby from actually flying AH.
I would say 50% of my enjoyment has come from buying books and learning about these aircraft.
The real problem arrises in my veiw is when we post a question and people in here immediately think we have some sort of weird alterior motive other than wanting it realistic. I guess its understandable when so many posts are aimed at annoying a particular group of players that the disussions turn into slanging matches, but if you read enough you should soon work out who is honestly just pursueing a hobby.They actually enjoy just as much being proved wrong as finding out they are right.
I have seen that you post on all subjects fairly and even better you are prepared to see that we are all capable of 'noticing' a problem even though some may not have the ability to work out mathmatically what they have felt.Im glad you do what do and even better you often explain how you did it, "it makes good readin' dude" , keep it going....:D hehe
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Hello,
for me it seems like the planes miss enginepower and on the other hand drag while strait flying.
The result is to much E-bleed and so a very fast slow down while turning.
As example: We can easy land the planes without power but full flaps in a very flat angel, and even without flaps. We nearly dont need power to keep the plane in the air, but then, if we give full power + WEP, i cant feel a real acceleration.
The acceleartion due to a dive seems to be much more powerfull than the acceleration due to the engine.
Its for sure not that bad, but a bit more drag and power and a bit less lift would be good i think. Then the planes would accelerate faster if they are slow, but at high speed all would be very similar like now.
Then the vertical manouvers would work better for the powerfull planes(good weight/power relation).
Greetings, Knegel
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I just checked the first training mission from the forgotten battles and they explain there some basic manouvers. the mission is flown with the Il-2 type 1, and for executing a loop they recommend 320 Km/h as the minimum required speed. This is around 200 Mph. Judging after this the Spitfire should be able to loop with lower speed. What do you think guys?
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F4UDOA, Do some research on sustain turn rates of airplanes. It will lead you to answereing your question about loops.
HiTech
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HT,
I understand that sustained turn rate is not the same as intantanious turn because the drag created in a max instant turn will be higher than the thrust available. Hence the aircraft can not sustain the turn.
I have the charts that show instant turns and they show the highest possible Cl max figure for that instant of the turn.
The factors for a high intant turn are
High Cl Max
High G load
Low wing loading
For sustained turn rate the two factors that I believe are missing are
High power
low drag especially Cdi
However cl max and wing loading remain important if not limiting factors.
I have the calculations for both turns although my math skills don't allow me to fully use them. However there are some drag calculators on the web that tell me enough of what I need.
I am using the stall and minimum loop entry speeds as a baseline for the different performance characteristics of individual A/C.
I am asking what conclusions if any can be drawn from that type of flight manual data.
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Hi F4UDOA,
Here are some similar looping values from finnish test flight report of a Bf109G-2:
Loop starting alt: 1000m
Starting speed: 500km/h
Speed at the top of the loop: 250km/h
Radius of the loop: 1100m
Alt gained after the loop: 150m
Time used for the loop: 26,5 sec
I do agree that these values in the pilot's notes and manuals are probably mainly for doing nice, beautiful looking airshow loops.
good topic, btw. :)