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This is one of 3 question in "series" - one question split up in 3 to better reward those responding about each aircraft. Other questions: Yak-131, L-159

A-10 is one 3 planes that are used in the ArmA 3 combat simulator, but its aerodynamics modelling currently lacks significantly. I'm planning on writing a short "essay" to developers regarding what and how can be specifically fixed in the flight model, but I'd like to back my research with some hard data. Specifically, I'm interested in any of the following:

  1. L/AoA
  2. D/AoA
  3. Side lift/SA (Slide angle)
  4. Max G/velocity
  5. Flight envelopes (like one below for F-15):

http://img704.imageshack.us/img704/7035/f15str.png

Torques can well be left out - it's not a full fledged simulator, but the above data can give quite a good estimation of high level characteristics already.

Are there any good sources on any of the above data? I've found some (see below), but the quality leaves a lot to desire. Low-mach data is good enough for me.

I understand this is a tall order, but, well, SE is for expert answers - maybe a wonder happens and someone here has it? :)

What I've found so far:

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  • $\begingroup$ Data like this is quite hard to come by. Civilian manufacturers of large aircraft charge simulator companies huge amounts of money (on the order of hundreds of thousands of dollars) for "data packages" that contain this stuff. It's going to be much, much harder to obtain similar data for military aircraft (no "need to know," and some of the data may still be classified). $\endgroup$ – TypeIA May 27 '14 at 16:25
  • $\begingroup$ On one side, yes. On the other side, the airframe is almost 50 years old, so it's not like it needs so much secrecy. Besides, there is a lot of educational material built on such famous and battle-proven aircraft usually. Similar F-15's data, for example, is circulating freely $\endgroup$ – DarkWanderer May 27 '14 at 17:19
  • $\begingroup$ You are aware that game physics and flight physics differ greatly, right?. Game physics must run in better-than real time; flight physics requires substantial mathematical effort to execute in real time. $\endgroup$ – Emily May 27 '14 at 21:20
  • $\begingroup$ I participated in the development of Rise of Flight sim, so yeah, I know that and I know how to model it. $\endgroup$ – DarkWanderer May 28 '14 at 5:26
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    $\begingroup$ I'm okay with a plot of how scared it is depending on AoA $\endgroup$ – DarkWanderer Feb 2 '15 at 21:41
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Good luck finding number 1-3 on your list. As far as I know these are proprietary data the you would have to get from Fairchild Republic. After a career of flying fighters I never saw this data or really care about it.

In my opinions numbers 4 and 5 on your list are much more relevant. What you are looking for are called EM diagrams. EM stands for energy maneuverability and these diagrams show a scale of turn rate, turn radius, airspeed and altitude to display meanueverability at a given energy state.

Using these diagrams you can find some key performance factors:

Min maneuvering airspeed - where the rate and radius slope drops off on the left of the chard showing min flying airspeed at given altitudes and wing loading

Max instantaneous rate of turn - max possible turn rate given a certain energy state - top of the rate curve then drops off

Max sustained rate of turn - maximum rate that can be achieved while maintaining your energy state (Ps = 0)

Corner velocity - velocity to achieve max rate at a given energy state

Min radius - smallest radius of turn acheveable given a certain energy state

Radius for given conditions - important to determine this when planning something like a targeting attack

I've found an A-10 EM diagram and a good Mig-21 diagram that annotates the factors I have defined above.

Note: I have to giggle at your "Low-Mach data is good enough for me" statement. There is no high-Mach data in an A-10. It will top out around .6 Mach (max speed around .7)

[Mig-21 EM Diagram] [A-10 EM Diagram]2

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  • $\begingroup$ In my opinions numbers 4 and 5 on your list are much more relevant. not if you want to simulate the aerodynamic behaviour (the stated goal behind the question) $\endgroup$ – Federico Apr 17 '16 at 20:37
  • $\begingroup$ Actually, without a full 6 degree-of freedom aerodynamic simulation, then programming the aerodynamic characteristics in the links he already has along with the realistic turn rate and radius limits from the EM diagram provided, he can get a realistic representation with normal gaming simulations $\endgroup$ – ahabf15e Apr 17 '16 at 22:51

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