I have used two-channel gyros on Zagi THLs :-)! But, they do little in helping pitch stability, when using extremely rearward CG, to my surprise, but are excellent in increasing lateral stability in turbulence. Someone wrote that adding rate gyros acts like increasing the inertia, making it somewhat easier to get ahead of the action! What could work is those 'autopilots' that use the horizon as reference, so they basically work when the aircraft is flying straight ahead, but help nothing in a turn! So they act like the 'return to normal flight attitude' gimmick MiG-29s have (connect it incorrectly and your aircraft will flip inverted when activated)! Have not tested my HAL 2001 autopilot yet, though (needs more space than a two-channel piezo gyro)! The HAL doesn't like flying low as trees and other obstacles interfere with its reference system (thinking the tree is part of the ground). These systems are said to have a Soviet Missile technology background, as they are simple and effective, as most Soviet technolgy was/is. Don't know if it is true, though! Heading holding gyros might work too, but cost a lot! Neither system would help in a spin! Tord, Sweden <URL:http://www.aricraft.com/tord/tord.html> <URL:http://home.beseen.com/hobbies/jebbushell/tord/tord.htm> -- If reply difficulties - use [EMAIL PROTECTED] Tord S. Eriksson, Ovralidsg.25:5, S-422 47 Hisings Backa, Sweden RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
