View Single Post
Old Nov 17, 2012, 10:49 AM
BAF23 is offline
Find More Posts by BAF23
The sky is the limit
BAF23's Avatar
Belgium, Vlaams Gewest, Hasselt
Joined Aug 2012
254 Posts
Originally Posted by Odysis View Post
During a turn, the heading is changing (hopefully), but the vertical gyro (yaw channel) can still have a zero rate.

Because the gyro is also tilted, the yaw channel doesnt' always line up with heading. This is easiest to understand if you think from the pilot's seat. Yaw means the aircraft nose moving left/right, not north/south. In a steady, coordinated turn, the attitude is stable. That's all the gyro can detect.

Vertical gyros are used in full size aircraft for yaw damping (helps hugely in assymetric too!), and you don't notice any weird reaction; the skidball just stays nailed in the middle.
If during a coordinated turn (with heading change) the yaw channel can have a zero rate, how do you explain the needle above the skidball (in a real aircraft) showing a deflection, being nothing but a pure yaw gyro?

Signflyer, does your answer mean that I have to make every turn by putting in a certain bank angle and keep giving rudder input into the turn for the whole duration till I want to rollout? With your answer, even an aileron rudder mix (I usually put in 10% when I cannot program differential ailerons) seems short of getting a continuous steady turn done.

Dave, what I liked about your explanation is that at some point "the plane will win" and allow the bank to change the yaw anyway (or a stable aircraft to revert to wings level after a while despite the roll gyro). It all starts making more sense now, especially after you gave the correlation with the specific aircraft stability and the adjustment of the gains. I'm flying scale with mild aerobatics and have no aspirations in 3D flying.

Thanks for the info guys, anxious to try it all out next spring.
BAF23 is offline Find More Posts by BAF23
Reply With Quote