View Single Post
  #2  
Old June 19th 04, 03:44 PM
Leslie Watts
external usenet poster
 
Posts: n/a
Default

I never noticed that much pitch up /down with yaw inputs with the
planes I fly, but I will try to give a reason for your observation.

I think it is due to p-factor rather than gyroscopic precession.

Let's take your right yaw. With the clockwise rotation that means the bottom
stroke of the prop is moving faster in the slipstream due to the forward
advancing
from the yaw. Higher speed = higher lift. The opposite would happen on the
top stroke.
This would give the pitch up.

I suspect the reason I never noticed it might be because the airframe and
motor mounting
might be designed to compensate, at least at one speed.

Les Watts

"xerj" wrote in message
...
Pitching a clockwise spinning (seen from the cockpit) prop forward will
result in a yaw to the left, pitching it up will result in a right yaw.
Correct so far?

However, why does a yaw to the right cause a pitch up, and a yaw to the

left
cause a pitch down? I thought it would be the other way, given that a yaw

to
the right means applying a force to the left of the prop disc, which would
result in the precession force being applied 90 degrees later meaning that
it would pitch DOWN. What am I missing?

Thanks in advance.