At 07:26 PM 9/19/2002 -0700, you wrote: >Donald Qualls wrote: > >>Picture two gyroscopes with opposite spin directions, and the frames >>locked rigidly together. When you tilt them, one gyro tries to precess >>one way, the other tries to precess the other way. If the angular >>moments of inertia and angular momenta are identical, the two precessions >>will cancel, leaving you with a gyroscopic device that will simply fall >>over instead of precessing. > > >If you need further proof, isn't this what most people do when they have >something rotating where they *don't* want gyroscopic effects? For >instance, in a helicopter: if all you have is your main rotor, you want >to be able to tilt, since that gives you the ability to translate >forward/reverse and left/right - split the main rotor's thrust into >vertical and horizontal components. One not-too-uncommon way to do >this is to have two main rotors, spinning in opposite directions. (A >slight difference in rotation speeds can also let you induce angular >momentum, turning the helicopter left/right.)
Tail rotors and counterrotating blades are to neutralize motor shaft torque, they aren't related to stability. John Carmack _______________________________________________ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list
