Aces High Bulletin Board
General Forums => Aces High General Discussion => Topic started by: SgtPappy on September 28, 2008, 10:23:16 PM
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I had a discussion about Spitfires vs Mustangs with a friend recently and we were discussing about the fact that, even though the Spitfire was renowned for its turning, the Mustang could outturn the Spitfire under certain circumstances. One of those circumstances being high speed. He asked me why and I couldn't really say. So the question is...
What is the reason as to why higher wing-loaded aircraft have better turn rates than lighter wing-loaded planes?
First I thought it was because the heavier-wingloaded planes are generally heavier and maintain more speed at the same given AoA allowing for a better turn rate. However, if that is so, the lighter plane would burn off its speed quickly enough to gain a turn rate advantage via AoA rather than speed. Hypothesis #2 states that the heavier wing-loaded planes burn off speed faster since they burn off more speed for the same given AoA, thereby tightening the turn radius.
Has me flustered, Ladies and Gentlemen.
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Well, Here is what i know and you can take this for what it worth. i fly RC aircraft and i know that a lighter wing loading plane will turn tighter than a heavy wing loaded airplane at slow to normal speed. but at high speed the high wing loaded plane will out turn the lighter because of the lift the heavy is creating at higher speeds.
you see the Stang generates a lot more lift at higher speeds than say a spit. So, When you turn the plane and yank on the stick, essentially, your "Climbing" horizantally. Since the 51 can generate more lift at higher speeds you get a tighter turn. I am sure that some aeronautical engineer will come on here and dispute this but....This is my story and im sticking to it :lol :lol
Even the F4U will turn tighter at higher speeds for the same reason. It also has a lot to do with the shape of the wing itself. The 51 had a laminar flow airfoil that was thick while the spit had a normal airfoil and a thinner wing. With the thicker wing you can take tighter turns at higher speeds because they do not "flex" as much thus giving you better stability at higher speeds allowing the wing to do its job......Generate lift.
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Good post guys. I actually read this one :aok
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the pony can deploy a notch of flaps at high speeds and spits can't ?
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Lots of good info :aok
^what he said
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I would have to agree with GhostBer. Makes sense. BTW this is a great post! :rock
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the pony can deploy a notch of flaps at high speeds and spits can't ?
I believe the pony can deploy 1 notch of flaps up to 175....The spit cannot agina i think it is due tot he shape of the wing. Can you imagine if the spitty were able to deploy flaps at higher speeds?? We would ALL be flying spits and turning on a dime!
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A spits flaps deploy at 100% It would physically be impossible to deploy 100% of flap anywhere even close to 200Kts.
If you could deploy fractions of flap like most other aircraft then maybe, but still above 200Kts it's a risky proposition.
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I believe the pony can deploy 1 notch of flaps up to 175
Actually the 51 can deploy its flaps at 400mph.
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Actually the 51 can deploy its flaps at 400mph.
yep :aok
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RL 109s could deploy 10% flaps up to 700kph
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wow, i didn't know that. maybe one day i'll fly one of those 109s .....a captured one that is :D
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The wikipedia article uses roll rate as an example of high speed maneuverability, but here ya go:
http://en.wikipedia.org/wiki/Compressibility#Aeronautical_dynamics (http://en.wikipedia.org/wiki/Compressibility#Aeronautical_dynamics)
Compressibility is an important factor in aerodynamics. At low speeds, the compressibility of air is not significant in relation to aircraft design, but as the airflow nears and exceeds the speed of sound, a host of new aerodynamic effects become important in the design of aircraft. These effects, often several of them at a time, made it very difficult for World War II era aircraft to reach speeds much beyond 800 km/h (500 mph).
Some of the minor effects include changes to the airflow that lead to problems in control. For instance, the P-38 Lightning with its thick high-lift wing had a particular problem in high-speed dives that led to a nose-down condition. Pilots would enter dives, and then find that they could no longer control the plane, which continued to nose over until it crashed. Adding a "dive flap" beneath the wing altered the center of pressure distribution so that the wing would not lose its lift. This fixed the problem.[4]
A similar problem affected some models of the Supermarine Spitfire. At high speeds the ailerons could apply more torque than the Spitfire's thin wings could handle, and the entire wing would twist in the opposite direction. This meant that the plane would roll in the direction opposite to that which the pilot intended, and led to a number of accidents. Earlier models weren't fast enough for this to be a problem, and so it wasn't noticed until later model Spitfires like the Mk.IX started to appear. This was mitigated by adding considerable torsional rigidity to the wings, and was wholly cured when the Mk.XIV was introduced.
The Messerschmitt Bf 109 and Mitsubishi Zero had the exact opposite problem in which the controls became ineffective. At higher speeds the pilot simply couldn't move the controls because there was too much airflow over the control surfaces. The planes would become difficult to maneuver, and at high enough speeds aircraft without this problem could out-turn them.
I don't think the answer has anything to do with wingloading because an aircraft with low wingloading generates more lift than one with high wingloading at any speed.
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Compressibility is an important factor in aerodynamics. At low speeds, the compressibility of air is not significant in relation to aircraft design, but as the airflow nears and exceeds the speed of sound, a host of new aerodynamic effects become important in the design of aircraft. These effects, often several of them at a time, made it very difficult for World War II era aircraft to reach speeds much beyond 800 km/h (500 mph).
This is true but i don't think this effects the turning ability of a particular aircraft.
Some of the minor effects include changes to the airflow that lead to problems in control. For instance, the P-38 Lightning with its thick high-lift wing had a particular problem in high-speed dives that led to a nose-down condition. Pilots would enter dives, and then find that they could no longer control the plane, which continued to nose over until it crashed. Adding a "dive flap" beneath the wing altered the center of pressure distribution so that the wing would not lose its lift. This fixed the problem.
While the P38 has a huge issue with compressability it had nothing to do with the shape of the wings or the wings themselves. It was due, In a small part to the actual design of the airplane, and the small size of the control surfaces. Once the airflow exceeded a certain speed the control surfaces were ineffectual due to the fact that they couldn't divert enough of the air to change the attitude of the airplane. Yes...This was fixed by the dive brake but only because it slowed the aircraft down enough to allow the small control surfaces to do the job.
A similar problem affected some models of the Supermarine Spitfire. At high speeds the ailerons could apply more torque than the Spitfire's thin wings could handle, and the entire wing would twist in the opposite direction. This meant that the plane would roll in the direction opposite to that which the pilot intended, and led to a number of accidents. Earlier models weren't fast enough for this to be a problem, and so it wasn't noticed until later model Spitfires like the Mk.IX started to appear. This was mitigated by adding considerable torsional rigidity to the wings, and was wholly cured when the Mk.XIV was introduced.
WOW! I didnt even know about this one. If that is the case then what i said in my previous post holds true. This also means that the Spit MK XIV should be the best turning airplane in the game..Spit pilots?? Anything to add??
I don't think the answer has anything to do with wingloading because an aircraft with low wingloading generates more lift than one with high wingloading at any speed.
Actually Anaxogoras, The light wing loading airplane will generate more lift at slower speeds than a heavier wing loading airplane. Usually lighter wingloading airplanes have an airfoil that is either semi symetrical or a flat bottomed. If you look at say.... a Cessna, the wing has more curve over the topof the wing than the bottom. This allows good slow speed stability and more lift.....But it cuts down on the areobatic ability of the airfoil because at higher speeds it generates less lift and the flat bottom airfoil is inherantly stable in slower speeds and doesnt really allow for radical or dynamic manuvers.
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Ok Gentlemen, I see much confusion.
"the Mustang could out turn the Spitfire under certain circumstances"
This statement must be more clearly defined.
First we must define what the word TURN means.
The word TURN typically is used for 2 types of things.
1. Instantaneous turn. This is simply based on 2 things
A. Stall Speed. (In general relates to wing loading but wing loading is only a quick approximation, Max LCO must also be considered) Lower stall speed the plane also turns faster.
B. Max G Limitations. This is either based on pilot or plane. (You can not exceed either in a turn, or your brake the airplane, or G lock the pilot).
2. Sustained turn. I.E. Max Degrees per second that can be done with out loosing speed.
This depends on wing loading, drag, thrust and can change for each plane at different speeds.
I do not know the numbers of the top of my head for all the spits and the stang, but it could be possible for a stang to have a better sustained turn, with a worse instantaneous turn than the spit.
HiTech
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Holy cow.... spell check works! :aok
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"the Mustang could out turn the Spitfire under certain circumstances"
This statement must be more clearly defined.
First we must define what the word TURN means.
The word TURN typically is used for 2 types of things.
1. Instantaneous turn. This is simply based on 2 things
A. Stall Speed. (In general relates to wing loading but wing loading is only a quick approximation, Max LCO must also be considered) Lower stall speed the plane also turns faster.
B. Max G Limitations. This is either based on pilot or plane. (You can not exceed either in a turn, or your brake the airplane, or G lock the pilot).
2. Sustained turn. I.E. Max Degrees per second that can be done with out loosing speed.
This depends on wing loading, drag, thrust and can change for each plane at different speeds.
I do not know the numbers of the top of my head for all the spits and the stang, but it could be possible for a stang to have a better sustained turn, with a worse instantaneous turn than the spit.
HiTech
i couldn't agree with you more. I think we were going with the sustained turn as this would be about airflow over the wing itself. I also agree with you that the Mustang will probably have a higher sustained turn than the Spitfire. The Spitfire will ALWAYS have a higher instant turn than the Mustang simply due to weight.
i also wanted you to know that in now way was this thread a slam against HiTech. I think you guys have a done a heck of a job with this game. Keep it up!!
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Given a certain speed then?
Also depends on alt and what engine, - or hp rather at that alt. Not just wingloading....power is there too )
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Oh yes of course, thrust is a huge factor. The only reason why the Me262, Me163 and P-38 outturn a lot of lightly-wingloaded planes is because they have that huge thrust factor (and good flaps in the P-38's case) allowing them to turn with a better rate than many of the lighter-wingloaded planes.
But, for planes like the Mustang vs Spitfire, the designs are quite conventional and thrust, though a large factor, is probably not more of a deciding factor than the wingloadings. Sorry HiTech. I should be more specific. What I meant by the Mustang turning better under circumstances was that the Mustang had a better horizontal turn rate than the Spitfire under certain circumstances whether the turn be instantaneous or sustained.
Also a bit of clarification, the P-47 and P-38 dive flaps were not slowing down the plane in in order to pull them out of shock stalls.. They were not dive brakes, they were dive flaps. They changed the pressure of the air under the wing in such a way that lift would be regained.
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I often take a P51D up to about 19k with a Spit 16 behind me then drop my nose slightly to build speed. The Spit will come along willingly because he thinks he has a chance and then at about 475 I start turning (not a hard turn) with the nose still down. Usually about the time he is looking out the side of his canopy at me he will roll and dive hard with me right behind him. :D :aok
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A lot of the answer has to do with "wing shape". Look up wing shapes and air speed and you will find the answer. The shape is related to lift and speed.
P51's have a flat wing endge and spits have rounded except for the s16.
Ask your self why a spit 8 can out turn a spit 16 and you have the answer.
:salute
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I often take a P51D up to about 19k
WOW
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Some of the minor effects include changes to the airflow that lead to problems in control. For instance, the P-38 Lightning with its thick high-lift wing had a particular problem in high-speed dives that led to a nose-down condition. Pilots would enter dives, and then find that they could no longer control the plane, which continued to nose over until it crashed. Adding a "dive flap" beneath the wing altered the center of pressure distribution so that the wing would not lose its lift. This fixed the problem.[4]
This is correct.
While the P38 has a huge issue with compressability it had nothing to do with the shape of the wings or the wings themselves. It was due, In a small part to the actual design of the airplane, and the small size of the control surfaces. Once the airflow exceeded a certain speed the control surfaces were ineffectual due to the fact that they couldn't divert enough of the air to change the attitude of the airplane. Yes...This was fixed by the dive brake but only because it slowed the aircraft down enough to allow the small control surfaces to do the job.
This is very incorrect.
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What is the reason as to why higher wing-loaded aircraft have better turn rates than lighter wing-loaded planes?
Better power-loading? As an extreme example, modern jet fighters that have more thrust than weight can maintain their maximum turn rate, pulling as many Gs as the pilot can stand 'till the fuel runs out. No prop-fighter can pull itself around against the drag generated by being at the maximum angle of attack very long. I believe you'll find the average fighter in this game can go around a flat circle pulling 3.5 Gs at best. But some have much more thrust than others. Thus, we would expect that a 109K4 could sustain a higher rate of turn than a HurriMK1, even though the latter's lighter wing-loading allows it to fly a tighter radius.
Hypothesis #2 states that the heavier wing-loaded planes burn off speed faster since they burn off more speed for the same given AoA, thereby tightening the turn radius.
I believe this would have to be it. Spits retain energy in turns in this game in a way that is just freakish and hard to believe...I'll leave it at that. A P-51, with higher wing-loading and flaps that can be dropped to increase drag, can decelerate better in high speed maneuvering and thus conceivably get down to its corner velocity quicker, if both start out well above corner speed. It also rolls better than non-clipped wing Spits above 375mph IAS.
This would be the only explanation I could think of for a P-51 ever "out-turning" a Spit, since a contemporary Spit is superior in both wing-loading and power-loading at typical AH altitudes, and does not suffer from elevator authority issues at high speed either.
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Bnz power loading as in regards to sustained turn rate, weight has nothing to do with the calculations. So do not think of power/weight but rather power/drag.
Think of the sustained turn rate issue this way.
A zero (a6m2) top speed on deck is 270 mph, a p51 is 355. So at 270MPH if the zero tries to turn on the deck, he will slow down. So a zeros sustained turn rate at 270 MPH is 0 Degrees per second.
The p51 at 270 MPH can maintain 270 MPH and turn at some rate greater then 0 with out slowing down.
HiTech
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Bnz power loading as in regards to sustained turn rate, weight has nothing to do with the calculations. So do not think of power/weight but rather power/drag.
Good clarification there, although I believe I mentioned power v. induced drag in the turn.
Think of the sustained turn rate issue this way.
A zero (a6m2) top speed on deck is 270 mph, a p51 is 355. So at 270MPH if the zero tries to turn on the deck, he will slow down. So a zeros sustained turn rate at 270 MPH is 0 Degrees per second.
The p51 at 270 MPH can maintain 270 MPH and turn at some rate greater then 0 with out slowing down.
HiTech
Makes sense, but if the turn is very hard at all, the P-51 will quickly bleed down below 270mpp. How would this information be useful for "out-turning" a Spitfire?
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Makes sense, but if the turn is very hard at all, the P-51 will quickly bleed down below 270mpp. How would this information be useful for "out-turning" a Spitfire?
If i am not mistaken (And i have been quite a few times on this thread! :rofl :rofl) I believe that the Stang, Turns sharper at lower speeds but cannot hold that turn for very long because of the bleeding of E. A spitfire can sustain its turn through almost any speed and this is why the Spiut is prefered by noobs because it is easier to turn and burn which is what most noobs see as a dogfight. Those of us that have been playing this game for a while know that you can "Dogfight" with almost any airplane as long as you know how. It is something that is learned and can only come with time.
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Hey Pap, what do we have to pay you for MORE posts like this? I never thought
of that one while my knuckles went white while twisting my "Saitek" into oblivion.
Think there might be an "Einstein" answer of "Relativity",E=MC (or whatever that
was about mass + speed = ??)
Really, after all the whiner and cryer "Tard-Threads", this is really nice! :salute TY
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It is deceptively simple really. A high wing-loading aircraft produces more drag in high-G turns due to needing a higher angle of attack to achieve the same lift. This means that in high-speed turns where both aircraft are limited not by lift, but by G tolerance, the high wing-loading aircraft is able to slow down quicker thereby being able to tighten the turn faster (Stang turning inside the Spit for example). If both aircraft keep a constant speed neither aircraft will be able to outturn the other (given the same G-tolerance), but WWII fighters didn't have the engine power to sustain high speed through high-G turns, and thus would slow down. The best turning speed of any aircraft is the speed where it is just barely able to generate max tolerated G. This speed is well below the maximum speed of WWII fighters and thus the plane that can slow down to this "best turning speed" the fastest is going to turn inside the other. However, as speed continues to drop the light wing-loading aircraft will gain the advantage as the game now turns to who can generate the most G out of the available engine power (i.e. sustained turn rate). This is why planes like the Fw and P-51 could outturn more nimble opponents like the Spitfire and 109, but the advantage was only at high speed and only as long as the fight didn't slow down to a sustained turn fight.
My $.2
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It is deceptively simple really. A high wing-loading aircraft produces more drag in high-G turns due to needing a higher angle of attack to achieve the same lift. This means that in high-speed turns where both aircraft are limited not by lift, but by G tolerance, the high wing-loading aircraft is able to slow down quicker thereby being able to tighten the turn faster (Stang turning inside the Spit for example). If both aircraft keep a constant speed neither aircraft will be able to outturn the other (given the same G-tolerance), but WWII fighters didn't have the engine power to sustain high speed through high-G turns, and thus would slow down. The best turning speed of any aircraft is the speed where it is just barely able to generate max tolerated G. This speed is well below the maximum speed of WWII fighters and thus the plane that can slow down to this "best turning speed" the fastest is going to turn inside the other. However, as speed continues to drop the light wing-loading aircraft will gain the advantage as the game now turns to who can generate the most G out of the available engine power (i.e. sustained turn rate). This is why planes like the Fw and P-51 could outturn more nimble opponents like the Spitfire and 109, but the advantage was only at high speed and only as long as the fight didn't slow down to a sustained turn fight.
My $.2
20 cents?
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20 cents?
Whoops! Well it was a rather long-winded post, so I'll pay extra. ;)
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It is deceptively simple really. A high wing-loading aircraft produces more drag in high-G turns due to needing a higher angle of attack to achieve the same lift. This means that in high-speed turns where both aircraft are limited not by lift, but by G tolerance, the high wing-loading aircraft is able to slow down quicker thereby being able to tighten the turn faster (Stang turning inside the Spit for example). If both aircraft keep a constant speed neither aircraft will be able to outturn the other (given the same G-tolerance), but WWII fighters didn't have the engine power to sustain high speed through high-G turns, and thus would slow down. The best turning speed of any aircraft is the speed where it is just barely able to generate max tolerated G. This speed is well below the maximum speed of WWII fighters and thus the plane that can slow down to this "best turning speed" the fastest is going to turn inside the other. However, as speed continues to drop the light wing-loading aircraft will gain the advantage as the game now turns to who can generate the most G out of the available engine power (i.e. sustained turn rate). This is why planes like the Fw and P-51 could outturn more nimble opponents like the Spitfire and 109, but the advantage was only at high speed and only as long as the fight didn't slow down to a sustained turn fight.
My $.2
I couldn't agree with you more! This pretty much answer the OP's question as well. Well done Die Hard.
I am also with everyone else.....This thread is a breath of fresh air. When you look at the majority of the posts are about whiners, squeakers, cheaters, Bish - Nit - Rook sucks ETC. this post is definitely very nice and i think that i will try to post more like this one to break up the whining posts. We will see how it works.