Colin thanks for taking the time to reply. Like I said before We both have tail dragger time so the concept of compensating for p factor at the transition is not new but this planes reaction is more extreme than I feel safe with. However I like the idea of trying the roll @ partial power. there is plenty of runway for a gradual application of power and if raising the tail @ partial power produces a controlable roll then maybe the problem is just a learning curve for this craft. Again thanks for your help Wayne ----- Original Message ----- From: Colin <crain...@cfl.rr.com> To: KR builders and pilots <kr...@mylist.net> Sent: Tuesday, October 14, 2003 1:18 PM Subject: KR>Ground loops
Wayne, Keep in mind that P-factor is not the only response the aircraft will have. It sounds to me that what you are experiencing is what used to happen to alot of the WWII pilots when they went from low power J3 cub trainers, to Mustangs, and Corsairs. They did fine when starting their takeoff roll, with full power applied, until they raised the tail. Then the spinning blade became gyroscope and precession kicked in causing them to uncontrollably ground loop. These aircraft actually had to begin their takeoff roll with half power applied, and as they acquired rudder authority, then apply full power. Tri-cycle gear aircraft do not experience this due to the fact that they are already somewhat level when full power is applied, and the CG is between the nose wheel and the mains, allowing much better directional control until the rudder becomes effective. Since the aircraft mass is very light, Newton's Law says that very little force is required to deflect the aircraft into a new direction. Although the design may have effective rudder control in flight, during takeoff roll the engine torque, P-factor, and precession will challenge you to master it. The gyro of the blade reacts 90 degrees in the direction of rotation, from the force applied. This would be the same reactionary problem of directional control that one of the other KR drivers was having while performing high speed taxi tests. Due to the precession response of the aircraft, and the fact that the CG is behind the mains, but close to them, directional control can be touchy. I suggest some part throttle takeoff rolls, that are followed by a smooth application of power as rudder authority is gained. It might not be a short field, STOL takeoff, but it will be in control with room to spare. I fully intend to transition into my KR2 this way. I have flown some high performance tricycle gear aircraft that will almost ground loop, due to just P-factor and torque. Good luck! Colin & Bev Rainey KR2(td) crain...@cfl.rr.com Sanford, Florida FLY SAFE!!!!_______________________________________________ see KRnet list details at http://www.krnet.org/instructions.html
