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aboyd Certificates/Ratings/Crew Stations: 5. "RE: Humpty Bump technique" 10-13-02, 03:43z  Anyone thinking about competing should get a copy of the IAC "red book" which is the rule book for contest flying. In the judging criteria, it says that for a humpty, the length of the vertical and the radius of the half-loop at the top are NOT relevant. As long as there is a vertical established both up and down, and if you've got a constant radius, it's a "10". Sure, a longer vertical and smaller radius might look cooler, but don't start there. Most people slow down way too much before the pull or push. All you have to do is clearly establish a vertical upline - to avoid a judge's conference and a zero - and it's a humpty! If you can fly a round loop, you can fly a constant radius humpty. It can help to use a slightly higher entry speed. When they're starting out, most people tend to find the pull humpty easier than a push humpty. The negative G is so light in the push humpty, I don't think it's really very relevant to the difficulty. I have a theory, though. Think about what's happening with the propeller as you slow down, in a pull humpty with a lycoming: the gyroscopic precession caused by the pull will naturally cause a yaw to the right. However, the effect of the slipstream contracting is that it will strike the left hand side of the vertical fin and rudder, tending to yaw you left. They cancel each other out. This is nice. Now think about push humpty: the push will cause a yaw to the left (with a lycoming) and so will the slipstream. Oops. You may find yourself running out of right rudder in these circumstances. This is clearly seen during an outside loop, for example. So, avoid the problems caused by the propeller at slow speed and high power. Keep the speed up in the humpty. You will learn all about the effects of gyroscopic precession, slipstream, torque in other maneuvers such as the hammerhead. Hope this helps, -- aboyd@igs.net ATP http://www.webhost-canada.com/~boyd/team.htm Remove | Alert Edit | Reply | Reply With Quote | Top

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Subject      Author      Message Date     ID      Humpty Bump technique    CRodin       09-29-02              RE: Humpty Bump technique    TomParsons       09-30-02       1            RE: Humpty Bump technique    CRodin       09-30-02       2                 RE: Humpty Bump technique    TomParsons       10-01-02       3                      RE: Humpty Bump technique    TomParsons       10-11-02       4         RE: Humpty Bump technique    aboyd       10-13-02       5            RE: Humpty Bump technique    CRodin       10-20-02       7                 RE: Humpty Bump technique    aboyd       10-22-02       8                      RE: Humpty Bump technique    TomParsons       10-22-02       9         RE: Humpty Bump technique    RickB       10-17-02       6

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