Ray Allen Elevator Trim Tab trays

[U2fletch]

These trays are riveted to a rib, and bonded to the elevator tube using Loctite EA9394 structural adhesive. They replace the stock servo tab and mechanical trim mechanism. T3 Actuator Original v15.jpg

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T3 Actuator.jpg T3 Tray.jpg

[jim.mclaughlin924]

If I were doing it over, this is how I would go. I would do a rudder trim tab the same way.

[rv8bldr]

I put electric elevator trim in my 4A (mounted in the fuselage driving the original trim arms), but instead of a rudder trim tab I just re-used the elevator trim wheel and chain to tension the rudder return springs. I did an article in Beartracks a few years ago on it. I hooked the forward side of the rudder pedals (where the return springs attach) to 1/16" cable that ran through a couple of small pulleys up to springs connected to the trim wheel. The trim wheel is mounted horizontally under the throttle quadrant and you just move the wheel left or right to apply a spring tension bias in the direction you want the rudder to go.

Full disclosure: I am waiting for good enough weather to do my first flight so this has not been tested airborne. However, it works a treat on the ground and my Maule had a factory installed similar design (it only worked for "right rudder", though)

[SpruceForest]

We did something similar, but use 4130... nice to reduce overall trim system weight.

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[paulodonnell]

I'm placing just one Ray Allen servo in the tail area of my Patrol to actuate the original trim horn....tail feathers are already covered!

[TJ_Slice]

I'm placing just one Ray Allen servo in the tail area of my Patrol to actuate the original trim horn....tail feathers are already covered!

Is the Patrol trim a servo tab? Wouldn't that cause an issue with the trim?

[paulodonnell]

Yes I think the Patrol servo tab function should be unaffected (as I'm using the trim motor to just move the original horn in the fuselage) but would have lost that feature had I fitted twin servo motors in the elevators I guess.

[TJ_Slice]

I haven't seen the whole mechanism in action. I am guessing the trim horn in the fuselage stays stationary when you move the elevator, and the 'servo action' is caused by the relative position of the tab and mechanism in the horizontal stab?

[paulodonnell]

That's correct TJ as far as I know and why the servo is going in that location for me...