This is a brief description of the aerodynamic parameters used in Chuck Yeager's Advanced Flight Trainer. This is NOT a lesson in aerodynamics, although you may learn something about some of the forces acting on an airplane in flight. Please feel free to invent your own planes, if you make something that flies in an interesting way, please send it as a text file, or on disk to: Electronic Arts, 1820 Gateway Dr San Mateo CA., 94404 Att: Paul Grace First some notes: The plane files are in the AFT subdirectory, you can indentify them as *.FLY files. They are ordinary text files, and can be edited with any wordprocessor. They have the form of one signed numeric and a return character per line. The numerics are unitless; that is, they are not in Knots, Knewtons, or whatever. They are just scalars, so do not assume otherwise. I suggest that you copy an existing plane that is similar to what you want to make to a temporary file such as TEST.FLY, then edit TEST.FLY changing only one or two variables at a time and test fly the plane to see what your changes have done. When everything is right, you can rename your plane as you like, but remember to include the .FLY extension. Do not call customer service with questions, Electronic Arts will not support this feature. (you're on your own). Some aerodynamic conventions: (PLEASE see the manual pps 32, 33) Alpha is the angle the wing makes relative to the airstream as viewed from the end of the wing. Note that a plane flying straight up can have an Alpha of zero. Alpha is also known as the Angle of Attack. Beta is the angle the centerline of the plane makes relative to the airstream as viewed from above the plane. Beta is also known as the Sideslip Angle. Pitch is the rotation of the plane around its lateral axis Roll is the rotation of the plane around its longitudinal axis Yaw is the rotation of the plane around its vertical axis ________________________________________________________________________________ plane name no hints here... wing: 0=bi, 1=high, 2=low, 3=test This affects the look of the cockpit too... roll due to beta Sideslip causes the plane to roll, because flow over the upstream wing is different than flow over the other wing. roll damping Be careful with all of the damping terms, they create dramatic changes in aircraft stability at varying speeds. roll due to ailerons This is the effectiveness of the ailerons. roll due to rudder Because the rudder is above the center of gravity of the plane, the yawing force also has a roll component. roll due to engine The torque of the engine/propeller rolls the aircraft. pitch due to velocity As the plane changes velocity the center of lift moves fore or aft relative to the center of gravity, inducing pitch. pitch damping See the warning above about the damping terms. pitch due to elevators This is the effectiveness of the elevators. pitch due to angle of attack As the plane changes Alpha, the center of lift moves fore or aft relative to the center of gravity, inducing pitch. pitch due to landing gears The drag of the landing gear is below the center of gravity, so the gear tends to pitch the plane down. 0 means gear are not retractable. yaw due to beta As sideslip increases, the vertical stabilizer tends to straighten the plane. yaw damping Another damping term... yaw due to rudder This is the effectiveness of the rudder. yaw due to nose wheel This is the effectiveness of the nosewheel for steering on the ground. drag with flaps The drag induced by extending the flaps. drag with no flaps The basic drag of the aircraft. If this term is the same as the above, then the aircraft will not have operable flaps. This term combined with the thrust constant determine the top speed of the plane. This and the thrust constant also combine to determine the maximum altitude of the plane. (a high-thrust, high-drag plane will have a high ceiling, and vice-versa) drag due to alpha As Alpha increases, the wing creates more lift and therefore more drag. side force due to beta Beta slides the plane sideways side force due to rudder The rudder also slides the plane sideways. adjustment for alpha=0 lift The basic lift term. This is a term you should experiment with. lift due to alpha with flaps As Alpha increases, the wing creates more lift. Experiment with this too. lift due to alpha, no flaps come on now... get with it. (are you paying attention?) lift due to change in pitch A transient effect, related to the circulation of air around the wing during changes in pitch. nose heaviness of plane The plane's natural tendency to pitch down affects the planes "static stability". braking efficiency Obviously, but these are ground brakes only. flap pressure limit When will the flaps jam? positive G force limit When will the wings rip off? Be careful here, these are instantaneous measurements, and transient G's can be much higher than RMS values. When in doubt, use a very big number. landing gear friction ...When on the ground. thrust constant Have fun with this one... see my comments about drag above. thrust loss due to velocity The faster you go, the harder it is to go faster. dummy All "dummy" terms hold values used by the aerodynamic model, but are not plane- specific. Don't change these. pitch limit on landing Landing parameters... There are more at beta limit on landing the bottom of the list. They control the roll limit on landing "sturdiness" of the landing gear. ground impact limit on landing dummy See the comment about the "dummy" terms. yaw due to aileron The use of ailerons tends to yaw the aircraft in the wrong direction, that is, when you bank to the right, the right aileron decreases lift (and therefore drag) while the left aileron increases lift (and therefore drag) The right wing has lower drag than the left wing, which tends to yaw the plane to the LEFT (oops! That's why some modern fighters use spoilers instead of ailerons). time limit upside down Some planes use gravity feed fuel systems, which limits the amount of time they can spend in negative-G positions. negative G force limit In the manner as the positive G limit, remember transients can be very high. pilot red out G force Just how tough ARE you? pilot black out G force red line This is when the "exceeding Maximum Velocity" warning comes up. Choose the velocity you want for the warning, and divide (or is it multiply? I forget) by .73 roll damping on ground These are landing gear characteristics. Me, roll spring force on ground I'm into flying, not taxiing. pitch damping on ground pitch spring force on ground 0 speed ground attitude forward pitch limit when landing This should go up with the other landing parameters... dummy dummy dummy dummy limit on steering More steering parameters... p turning rate limits Steering q turning rate limits Steering r turning rate limits Steering