REFLECTOR: FW: Aileron torque tube bearing

[John Tvedte]

Al,

Personally I think these bearings are of general poor quality.

General Bearing part#: 32264-88-302 - and as far as I know, are used throughout the control system.

I have not sourced a better quality product at this time, but am working on it.  We are looking at Timken.

I have a couple retired engr's from Rockwell helping me - they didn't really like the tolerance of the bell crank to inner race either, and thought a capture spacer should be added on the inboard side when the bell crank is inserted.  They also suggest complete encapsulation of the outer flange - could be as simple as an aluminum ring.

I'm not sure of a timeline on my research - I'll get back to you with results.  Also attached are some encapsulation rings, designed by John Leder.

John
________________________________
From: reflector-bounces at tvbf.org [reflector-bounces at tvbf.org] On Behalf Of Al Gietzen [ALVentures at cox.net]
Sent: Tuesday, June 03, 2008 10:35 AM
To: reflector
Subject: REFLECTOR: Aileron torque tube bearing

I find that one of the aileron torque tube bearings at the bellcrank in the engine compartment has failed. It now has about 1/16” play, and slack in the controls is not a good thing. This seems a bit peculiar to me as the normal motion is slow and limited, and the normal loads minimal.

Is this a unique occurrence, or have others had this happen?  The underlying question is vibrational loads; lateral or torsional, that may have some resonance – like in that 4-5 ft length of unsupported torque tube.

Al
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