CG location w and w/o pitch rate gyro

[INewton]

I usually move the cg back until my planes start to become a bit 'snappy'. When I recently stated installing pitch rate gyros, it didn't seem to matter where I move the cg; the planes always remain neutral.

Is there aerodynamically speaking, a 'best' spot for the cg when there's active feedback on the pitch?

[Sparky Paul]

The gyro is faster at cancelling pitch rate than you are.
It adds stability regardless of the c.g. location.

[INewton]

The gyro is faster at cancelling pitch rate than you are.
It adds stability regardless of the c.g. location.

Well yeah, the planes appear stable regardless of cg, but are there other factors, eg drag, that vary? If so, is there a rule of thumb that points at an optimum location for different operating regimes (slow speed flight, high speed/high angle of attack, or just plain hotlining)?

Thanks!

[Sparky Paul]

Automatic feedback into the pitch system can make anything flyable.
We modified a Tristar to have the inflight c.g. aft of the main landing gear.. by pumping water aft into large tanks, once in the air.
The plane's efficiency improved.. it could fly at a lower angle of attack, cutting the drag.
The response in pitch was interesting, the plane more "translated" up and down than changed the deck angle when manuvering. Unusual feeling in flight.
The F-16 and later planes are almost unflyable without the augmentation that keeps the pointy end at the front.

[INewton]

Automatic feedback into the pitch system can make anything flyable.
We modified a Tristar to have the inflight c.g. aft of the main landing gear.. by pumping water aft into large tanks, once in the air.
The plane's efficiency improved.. it could fly at a lower angle of attack, cutting the drag.
The response in pitch was interesting, the plane more "translated" up and down than changed the deck angle when manuvering. Unusual feeling in flight.
The F-16 and later planes are almost unflyable without the augmentation that keeps the pointy end at the front.

The Tristar is a nice model but rare nowadays. The RR fans are also prone to cracking. I'd like to get one, but my model club doesn't allow three holer heavies.

[Ollie]

http://www.charlesriverrc.org/articles/asfwpp/helmutlelke_asfwpp.htm
http://members.cox.net/evdesign/pages/spiral_stability_gyro.html

[INewton]

http://www.charlesriverrc.org/articles/asfwpp/helmutlelke_asfwpp.htm
http://members.cox.net/evdesign/pages/spiral_stability_gyro.html

Thanks a bunch. You led me to a real nice hotliner field in Framingham I never knew about. :D