How maneuverable were they?

Discussion in 'Flight Test Data' started by Col Hajj, Jan 29, 2010.

  1. Col Hajj

    Col Hajj New Member

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    Is there a consolidated list out there some place that gives data on various plane statistics like roll rate, turning radius, and other “maneuverability” stats?

    Thank you,

    Keith
     
  2. davebender

    davebender Well-Known Member

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    Check out some of the air combat simulator sites like the one above. I suspect some of them are pretty close to reality.
     
  3. Col Hajj

    Col Hajj New Member

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    Thanks Dave, that will give me some good reading to start with. I think you are right in that most sims will give me a good "ranking" of how planes preformed compared to each other... which is what I am ultimately after.

    Thanks again,

    Keith
     
  4. drgondog

    drgondog Well-Known Member

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    You would have to be able to peel the math model apart to make that judgment - I see no way that any of the Sim designers have accurate data for drag buckets for each type, Hp to altitude, prop efficiency by altitude by a/c type, energy models which take into account the drag profile by velocity, trim drag for high deflection rudder/elevator, etc. etc.

    In short some may be resonable at sea level in level flight, including climb as the standard aero performance sets are close - but it is a toss up at altitude for two stage engines, high altitude turn performance, true turn performance from SL to high altitude, effects of gross weight to the wing L/D as the ship nears stall profile.

    Look at the enrgy and emotion expended in various debates here for example. without a drag bucket which looks somewhat lie a bowl with Drag on vertical scale and Velocity on the horizontal scale, you have no idea where to get Total Drag except for the far right at Max Velocity for a flight test - simply because Thrust is totally balanced by Total Drag (induced, parasite and form drag) - and you can calculate Induced Drag component at that data point.

    But Parasite Drag is not linear and does not vary in a straight line as the airframe loses speed from top velocity -

    You have to have a Drag Polar (bucket) for each aircraft as well as relaible wing section plots for both CL as f(AoA) and well as Cd as f(CL) for the wing on that airplane... These are minimum accurate data in hand to come close to performance calcs, particularly in turn performance
     
  5. davebender

    davebender Well-Known Member

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    Gee, you think you could be a little more pessimistic? :p

    This forum has a section for flight simulators. You might even consider joining a flight simulator. Perhaps they aren't perfect but nothing is except taking the real world aircraft type out for a test flight.
     
  6. DAVIDICUS

    DAVIDICUS Member

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    #6 DAVIDICUS, Jan 29, 2010
    Last edited: Jan 29, 2010
    "You would have to be able to peel the math model apart to make that judgment."

    That point can not be stressed enough. And right off the bat, they have the wing area and max weight wrong on the P-47D.
     
  7. davparlr

    davparlr Well-Known Member

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    Good post. Fresh out of college, but with 5 years AF flying time behind me, I was assigned the task of computerizing max range performance of the F-5 for display on an Horizontal Situation Display. Going to one of the aerodynamicist with all my aeroperformance formulas in my head, I asked what were the formulas for fuel usage. I was quickly slapped down when the engineer, who was responsible for the flight manual data, stated that if he used formulas for the charts he would fired. He only used flight test data. So, I went to numerical analysis of graphs! As the Avionics Controls and Displays manager on the B-2, I had a major interface with the moving base B-2 flight simulator. The simulation of the B-2 was reported to be very good (I believe a lot of the flight control data was actually developed in the simulator and then programmed into the B-2 flight control computers) but I can tell you that Northrop Grumman spent a whole lot more money on the B-2 simulator programming, with a lot more talented aerodynamist, than a game company has ever spent on a game!
     
  8. drgondog

    drgondog Well-Known Member

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    Dave - on top of everything else thrust for a jet engine is much more straightforward than a prop disk and drag interference is also more complicated for a propeller wash with the turbulent tube..even 'calculating' lift on the wing has its issues due to the signifcant amount of highly turbulent flow over the wing in the stream tube.

    When you were doing your project your guy could have given you sfc for the engine on a test stand but it is a complicated task integrating the cruise equations as the airframe loses weight due to fuel consumption and the wing changes angle of attack as the weight decreases, etc, etc.

    My eyes glaze over when the sim 'engineers' jump into these discussions..if Aero was easy everyone could do it.
     
  9. davparlr

    davparlr Well-Known Member

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    Yep. All you say is correct.
     
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