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Re: Elevator Trim Tab

>    Why reinvent the wheel?  Spring trim works fine and is the norm on several
> aircraft, both experimental and certificated.  It also is simpler, has no
> hinges to wear or pins to work out, and is probably lighter.

Hmmm, why reinvent the wheel?
My biggest reason is that the wheel is there and it can be reinvented.
It's not that the spring trim is broken, I just think it could be done
better.  I'm a tinkerer, and like the challenge.

There are several reasons why I think a trim tab would be better:
1) weight:  I haven't weighed the stock actuator, but I'm sure
	it's over one lb.  There is also the fiberglass hoop
	and several layups ... oh, and a wooden block to keep
	from going over center.  Servos weigh several ounces.
2) response:  The actuator requires several seconds to travel
	full deflection.  Some of the servos I am looking at
	travel 60 degrees in .2 to .3 seconds.  Servos are
	active devices in that they are set and forget.  Tell
	them where to go and they stay there if they are disturbed.
	Of course they require constant power and constant 

Brian Michalk  <http://www.awpi.com/michalk>
Life is what you make of it ... never wish you had done something.
Aviator, experimental aircraft builder, motorcyclist, SCUBA diver
musician, home-brewer, entrepenuer and SINGLE!