Author Topic: Remodeling the flight model  (Read 8434 times)

Offline ccvi

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Remodeling the flight model
« Reply #150 on: July 03, 2003, 01:31:31 PM »
When going super sonic lift shifts forward. That's why modern fighters have their wings so far in the back.

Offline Straiga

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Remodeling the flight model
« Reply #151 on: July 03, 2003, 04:01:40 PM »
Clouds Your right the F-111 was not made for dog fighting it was designed for all weather strike fighter using terrain following radar to fly nap of the earth to hit its target. F-14 is quite manuverable for what it is. The tomcat was design to carry the AIM-54. It can carry six and stand off over a 100 miles, than launch all six on six seperate targets. I just used the F-111 and F-14 to show that CG and center of pressure can change with the sweep of the wings.

Later Clouds

Offline clouds

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Remodeling the flight model
« Reply #152 on: July 04, 2003, 02:57:37 AM »
Uhm......ccvi......the F-14 have two little winglets deploying out from the upper part of the jet intakes and they could have to adjust the horizontal stability during SS cruises if I remember well (tell me if I'm wrong). So it seems, at least in the F-14, this sort of little canards could add a little bit forward lift positioned absolutely forward the CG. Could these devices be used to raise or down the F-14 nose ? I have no infos about this.

Bye

Offline bod

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Remodeling the flight model
« Reply #153 on: July 05, 2003, 12:40:26 AM »
Anybody with a PPL or higher should know that the horizontal stab has a negative lift vector, and the reason being stability. With artificial stability (f-16 and other modern fighters) CG can be moved aft so that the tail produces lift.

The most complex of all flying things are birds. They are unstable in all axis (pitch, roll and yaw), can move their cg and lift vector etc.

Offline hazed-

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Remodeling the flight model
« Reply #154 on: July 05, 2003, 06:43:18 AM »
arent we supposed to be giving info to pyro which might be incorperated into the new model? what the hell has F16's and F111's got to do with his request?

Its all very good that you guys know your aerodynamics but please keep things RELEVANT to WW2?

otherwise pyro will not bother reading this thread if it gets filled with irrelevant Flight dynamics. Modern jets dont bear much relation to piston engines.

For me id like to ask pyro if he has factored in the different types of aileron and control mechanisms.

For instance modern stunt aircraft that need stability in lateral and horzontal pitch and roll and yaw control used control rods to connect the joystick/yoke. Only a few WW2 aircraft used this method and the rest used the far less 'crisp' wires and pulleys.
The two aircraft i know of so far that used control rods are the F4U's and the FW190s.
It would seem according to an interveiw i saw with a modern stunt pilot that the control rods give much more precise and instant control.The pulleys and wires systems would also stretch over time and make the fighters lose their crisp handling.

So my question is why do both these aircraft behave almost identically to others when the fact that modern stunt aircraft use control rods clearly points to an added benefit of this method of control.
THe area where we would or should notice this the most is when we have to use fine and delecate control of the aircraft.In vertical climbs as the speed drops off and you allow gravity to pull you over both these aircraft should have a notably better feel to the controls.I would have thought the same thing would be noticable in suustained turning on the limit of stalls.Whereas wire controls would require a slight opersite lock to counter the give in the wires etc the control rod aircraft should have a much more precise feel. How about it pyro? has any of this been factored in?

I know its a small matter but its the small improvements that add up to a superior aircraft. Im not complaining but for the 190 already it has many of its novel features unmodeled. None are major but addded together it soon becomes a rather large chunk of what actually made them special.

For instance in WW2 there were very few aircraft with any form of auto pilot. In AH we all have auto pilot with X,alt X, shift X etc but in WW2 when 190s were introduced it came with one of the first computer autopilots. It handled mixture rates and propellor pitch control among other jobs. This took a lot of load off the pilots mind and allowed him to better concentrate on fighting,Which is what they were there for after all.In AH this clever inovation has no benefit for the 190.Whilst allied pilots were focusing on their engine management it was to the detrement of their SA, not so in AH
It also had an electric fusing sytem for its bombs which could be set whilst inflight by the pilot. This meant timed fused or impact fused bombs allowing for a choice of how the weapon was deployed. This is also irrelevan in AH but was a huge improvement at the time.
The 190 was also supposedly a very stable aircraft at all speeds needing very little trimming.It didnt have adjustable trim because it handled so well they decided to remove tham and use small tabs instead. In AH the 190 needs constant trimming as you increase speed and it also seems to take a longer period to settle from a climb trim to a level trim if you use auto level.Why is this? shouldnt it be very quick to sort out the trim if this aircraft was as good as it seems it was? (plus the control rods mentioned above)
MW50 and GM1 was used by the 190s and these were superb systems.In AH we all have a very similar system of wep for all aircraft but in WW2 many early allied and almost all russian aircraft had no such systems. The La7 for instance had a severe limit on emergency power use.It was a 2 minute limit according to the pilots manual! not so in AH eh? :) .The same applies to many aircraft.The fuel for these systems which affected how long you could use them was also a major factor in favour of 190s etc. They carried much larger supplies than even some of the latest allied types.This meant they had advantage in longer protracted fights.As the allied planes ran out of wep or additives the LW aircraft had more left.
This would make a big difference but with AH's wep system its hardly noticable as any advantage, in fact as the weights of the gm1 and mw50 systems is still modelled they actually work against the aircrafts ability.
The seating position on the 190 was distinctly cambered back to allow for greater pilot tollerance of G's because of his seating position and its used in modern fighters in a similar way,I believe P47s also had this tilted or more reclining seating position yet neither aircraft seem to have any advantage in levels where blackout occours in AH.
I know its small things but they do add up to the overall package.Im ok with the way AH is modelled in wep etc but I do feel it doesnt represent the WW2 systems too well and aircraft with metanol and nitrious in real life have little if any advantage in AH over those that didnt back then in RL.Add this to the other 'little' things and soon you have half the innovations wiped out and you get a less than representive model dont you?

Id like to see all aircraft given their full range of benefits that the real aircraft introduced factored into the model. Things like laminar flow wings or the stukas automatic pull out computer etc. OH and of course the bad things too!
109s and 110s had a sliding leading edge slats that could deploy unevenly at certain speeds and would drag the wings one way or the other and throw off the pilots aim or cause premature stalls.
The me262 throttle was an absolute squeak!! if at certain alts you used it without following the rather delicate rules you would get a flame out and you couldnt restart the engine until you got below a certain alt (19k i think it was from memory).Also slamming the throttle open could destroy the engines. In AH you can do whatever you like in the me262 and this doesnt give us the 'feel' of being in a very new and very tricky to fly and dangerous jet.We can fly like maniacs with no penalties.
 
just my opinion of course but i feel much has been missed out.
« Last Edit: July 05, 2003, 07:21:02 AM by hazed- »

Offline Tilt

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« Reply #155 on: July 05, 2003, 08:02:52 AM »
Quote
Originally posted by hazed-
The La7 for instance had a severe limit on emergency power use.It was a 2 minute limit according to the pilots manual! not so in AH eh? :)  


from the pilots manual.................  the Ash82FNV was field rated to run 10 mins continuously at 2500  WEP and 30 secs (upon take of) at 2600.

The only referance I have ever seen to 2 mins was   recounted by Czech pilots flying the La5 FN.

Also FYI elevator and ailerons on the La7 were actuated thru tubular (rod linkages) rudder was actuated via cable linkages.
Ludere Vincere

Offline clouds

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Remodeling the flight model
« Reply #156 on: July 07, 2003, 07:31:06 AM »
WOW hazed !!!!...............you post looks huge like the British Encyclopedia is :D

Anyway u said lots of interesting things 4 me.

And.....what do u think about the Me163 fuel dissolving properties had ? (dissolving the pilot I intended) :p

Some time the plane lands intact but.....afther some minutes the pilots didn't get out, why ?.....because him vanished inside the cockpit. GULP!!! :rolleyes: :p
« Last Edit: July 07, 2003, 07:52:40 AM by clouds »

Offline hazed-

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Remodeling the flight model
« Reply #157 on: July 07, 2003, 08:13:32 AM »
Quote
Originally posted by clouds
WOW hazed !!!!...............you post looks huge like the British Encyclopedia is :D

Anyway u said lots of interesting things 4 me.

And.....what do u think about the Me163 fuel dissolving properties had ? (dissolving the pilot I intended) :p


yeah if i was HTC id model it lol. you could hear screams and stuff as your pilot dissolves after being hit in 163 :) hehe

Tilt i didnt know that! La7 had control rods too? The 2 minute limit was on a website that had the La7 in detail.I unfortunately lost all my 'favourites' so i cant post it or remember the addy  but I got the link from a post in this BB if i remember right. It caused a bit of a fuss when it was discussed in here.(btw there was also a load of info on the LA7 they fitted a rocket to!! it boosted its speed tremendously! can you imagine LA7s running around with rocket boosters!?! :D

EDIT: found the site!!! http://www.btinternet.com/~fulltilt/Engine.html

EDIT:This is your website tilt ! lol I didnt realise. But as you can see
it clearly says it can be run at maximum (2600rpm) for 30 seconds. Even less than the 2 minutes i thought it was. There is a 'Duration' in the list that says 10 mins but i cant see what that duration refers to. I assume this is what you are talking about? 10 mins from the manual? what is the 30 seconds referance all about?

Ive since sort of discovered that control rods and wires would (if recently adjusted) behave similarly.Only when heavy use stretches the wires do the control rods show their benefit.As AH models all aircraft in their factory fresh condition it doesnt factor in to the model.I have to concede i have got the wrong idea about how they would effect flight. They would affect performance if we used the same aircraft over time but not in the instant renew AH spawning :)

However I still feel its a shame in a way that we dont get to see the difference that the autopilot computer and fuse selector and MW50/GM1 systems made in real life. Its not HTC's fault to be fair because faced with the almost insermountable work it would take to somehow model the lifespan of a real engine with the limits it has in real life being totally out of phase with our quick up and go type of play. Perhaps TOD could try to model the realistic lifespans of a particular engine but that would require a huge, and probably unecessary change.Engines last for years! you can overabuse them or look after them and it all affects lifespan.

Tilt now i need to ask another question. If im correct HTC said the wep limits are set as the pilot manuals recommend. Or at least when i asked about this before thats what i was told(probably a customers idea of what it was but i think HTC sort of confirmed it).
Unfortunately it doesnt tally up. Just as you have just said, 10 mins of wep for the LA7 according to the manual? why is it 5 mins now in AH? The current times for wep are incomprehendable to me im afraid.heres a few examples

109 10 mins wep 10 mins to cool
190 10 mins wep 20 mins to cool
P51  5 mins wep 10 mins to cool
P47  5 mins wep 10 mins to cool
SPIT  5 mins wep 15 mins to cool
Hurr   5 mins wep 15 mins to cool

Ive never managed to understand how its worked out.

edit: Actually this is off thread topic Tilt, never mind.
« Last Edit: July 07, 2003, 12:58:29 PM by hazed- »

Offline Tilt

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« Reply #158 on: July 07, 2003, 01:16:23 PM »
Quote
Originally posted by hazed-

EDIT: found the site!!! http://www.btinternet.com/~fulltilt/Engine.html

EDIT:This is your website tilt ! lol I didnt realise. But as you can see
it clearly says it can be run at maximum (2600rpm) for 30 seconds. Even less than the 2 minutes i thought it was. There is a 'Duration' in the list that says 10 mins but i cant see what that duration refers to.


Std WEP is the 2500 rpm figure............. the reference to 2600 can only be found in the La 7 manual......I doubt it was ever used in flight.......however you will note that the rev control would have permitted the pilot to set it! regardless of consequencies........

It is also my page refers to the la5FN having just 2 mins of WEP

http://www.btinternet.com/~fulltilt/Perform.html

I will admit this is contentious, if you click on the ! next to the 2min figure you will arrive at some speculation on my part and the reason it is given.

I do not know how HTC arrived at the WEP ratings given........... I do like them linked to engine temperature as IMO this would indeed have been the parameter the pilot would have watched. (in this case it {air cooled radial}would, I think, have been oil temp and pressure).

In a thread elsewhere we have discussed the niceties of WEP via over rev and  WEP via additive injection (water, methanol, NO etc) and how it would be neat to have them replicated.

Re rods and wires........ I know its my imagination.... but some times it seems to me that after prolonged periods of very high G my turning  ability is reduced.............. I think it probably has more to do with my inability to rid myself of what ever is on my 6;)
Ludere Vincere

Offline hazed-

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Remodeling the flight model
« Reply #159 on: July 07, 2003, 01:44:15 PM »
ahh ok my bad, i said La7 when i should have said La5.

I wont go over the wep business again.I had my bellybutton chewed off by hitech for asking before so id best drop it :) leave it to someone else to ask :) tilt :)

Offline rshubert

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Remodeling the flight model
« Reply #160 on: July 07, 2003, 02:01:53 PM »
Quote
Originally posted by clouds
Uhm......ccvi......the F-14 have two little winglets deploying out from the upper part of the jet intakes and they could have to adjust the horizontal stability during SS cruises if I remember well (tell me if I'm wrong). So it seems, at least in the F-14, this sort of little canards could add a little bit forward lift positioned absolutely forward the CG. Could these devices be used to raise or down the F-14 nose ? I have no infos about this.

Bye


The winglets "pop out" to adjust the center of lift when the wing sweeps, and are not adjustable in any way by the pilot or flight control system.

And yes, hazed, it is off the subject.

Offline rshubert

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In defense of Straiga...
« Reply #161 on: July 07, 2003, 02:35:27 PM »
He's absolutely right about the horizontal stabilizer.  It does, indeed, produce a DOWN force to counteract the FORWARD CG of (almost all) planes with a tail in the back.  I think the bleriot monoplane is an exception.

Look at the flight manual for any light plane.  The center of lift is AFT of the center of gravity.

Canard planes like Beech Starships and Velocitys have a canard that Lifts UP, and that's one fo thereasons they are more efficient designs.

The private pilot books produced by Gleim (or is it Gliem) explain this stuff in the chapter on aerodynamics.  It is published fact.

Offline joeblogs

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your work
« Reply #162 on: July 07, 2003, 10:08:27 PM »
Tilt

Have not been to your page in a while.  It is really great.  Nice editions and the citations are much appreciated.

-Blogs

Offline bfreek

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dork alert
« Reply #163 on: July 08, 2003, 11:38:27 PM »
ya got autolevel, autofly (comb trim), auto speed, auto that , auto this, dive bombing buffs, buffs flying thru hangers upside down, 10 million yard killing and ya'all fighting about this topic of torque and airflows?


LOL

god knows all the other odd stuff with the fighters,  who cares about the airflow

Offline oboe

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A6M FM changes
« Reply #164 on: July 28, 2003, 06:40:08 AM »
Hope you guys look at the A6M's drag numbers.   These must be among the most lightly wingloaded aircraft in the game, yet I've never been able to glide one to a deadstick landing...