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Trim/Servo Tab Adjustment

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Aug 28, 2007
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OK Gang, a little input requested: Got the bird out of its long and detailed (all winter) condition inspection and had an enjoyable and pretty successful 1.4test hop Wednesday. Only one problem noted; When it went in this winter, one of the squawks my A&P wrote up was that the servo tab pushrod was rusted and slightly bent. So I dutifully cleaned, painted, and straightened it, and reinstalled in the original horn holes at the original thread adjustments.

During the test flight, it was immediately apparent that there was now a pronounced pitch up tendency requiring forward pressure on the stick, even with full nose-down trim. Not so bad at 80-90 knots, but more and more pressure required at 110-120 (as you'd expect). Should note that it flew pretty much hands off before I screwed around with the pushrod.

I expected straightening the rod would have some effect but not to this extent. I know, the obvious fix is probably to just bend the rod again, but looking for more education on how the trim should be set up properly.

Joe C.

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