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Old 11-14-2003, 07:16 PM
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lov2flyrc
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Default RE: How about a "3D Waiver"?

Excellent posts Kevin!


J_R,
It's my understanding that turbine manufacturer's have some kind of rating system that implies or states speed capability.
I believe what you may be describing here is actually thrust output. Most manufacturers have a RPM = Thrust chart for their engines so that when we set up a turbine powered aircraft we can "De-rate" or lower the thrust output of the engine to match the airframe(IE: we set the max rpm in the engine, thus controlling or max thrust). Now, depending on the airframe, we may not always derate the engine to .9 to 1 settings. If we are flying a high drag airframe like an F-15 or Eurofighter, we benefit greatly from having more thrust to weight ratios, Takeoff and go-around maneuvers are much easier, vertical performance is improved greatly and the aircraft is vastly more maneuverable and controllable. Even at 1.5 to 1 thrust ratio, my eurofighter would never see 175mph at full throttle in a dive, the airframe just has too much drag! Why would I need to install a speed limiter in an airplane that is not capable of reaching 200mph? Thats like installing a retract valve on a plane with fixed gear, pretty silly..... I have attached a thrust chart for a Jetcat P-120 to give you an idea what I am describing..
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