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Rudder Trailing Edge Shape?

jsharkey

jsharkey

Well Known Member
I have an RV-6 with the larger couterbalanced but still folded trailing edge. I need a significant amount of rudder deflection during the take off roll and on the few times so far that I have had to do a forward slip while landing in a slight cross wind. Is this normal or is it possible that the trailing edge of the rudder needs squeezed to make it more effective? Otherwise she flies beautifully - feet and hands off in the cruise with the ball nailed in the middle.

Jim Sharkey
RV6 - Phase 1
 
It's normal, Jim

My -6A also needs a bunch of right rudder in the same conditions...it's also counterweighted and folded.

Regards,
 
After pondering this...

...overnight, Jim, there's more. In the first place, we have a high power to weight ratio in even the lowly 150 HP models and with a lot of fin/rudder area, the spiral airflow from the prop as it contacts such a large area from the left side, results in a good left yawing tendency. Regardless of the FAA's definition of "high performance airplane", which we do not fit, we are nevertheless, flying high performance airplanes and this is usually a trait of them.

In the taildraggers, the downward swinging prop blade has a lot more "bite" (think P-factor), than the up-swinging prop blade, adding to the yaw because of greater thrust on the right side of the airplane, until the tail comes up, then both prop blades have a more equal angle of attack.

FWIW, in really high HP airplanes like the Bearcat, Grumman threw in a good dose of nose-down engine tilt, this to help direct that spiral airflow over the top of the fin and help minimize the tremendous yaw caused by that 2000 or more horsepower.

Regards,
 
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