TruTrak GX Pilot

[armaurer]

Has anyone had to change a shear pin in one of the autopilot servos?
Told by TruTrak that the loss of lateral control...heading or tracking is caused by shear pin breakage.
Wondered if anyone has had to replace a broken one?
Cheers
Alan

[Pete D]

I have not heard of one shearing in a CC but I have heard of one or two breaking in other aircraft.

[N867SP]

Just pulled mine after loss of roll axis. Sheared at 485hrs. I’ve always felt like my aileron forces were on the excessive side, had hoped over time they would lessen, not the case. Feels like most of the resistance is in the torque tube and torque blocks, as when aileron cables are disconnected forces are pretty close to same. About 4lbs left or right...







Pete Meyer
Severna Park, MD
CCK-1865-0078
N9PW

[Daveembry]

Pete, I think a number of builders had a problem with the torque tube being too tight in the blocks. I was told that the specs on the torque tubes was +/- .005 which is enough to make it too tight if it’s on the thicker side. The blocks are suppose to be torqued down to 90 in lbs I believe. On the first couple I did, I was told to shim the blocks. I did a combination of shimming and a little less torque being sure there were 1-3 threads showing through the lock nuts.

They are shimmed very easily. Just take the belly pan off and you can get to the nuts for the front and rear torque tube blocks. Just back the off enough to stick some shims between the block halves. I cut up some aluminum coke/beer cans and use that material because it doesn’t take much.

I have since been sanding the blocks to back them bigger if needed so that it wasn’t so tight.

Just pulled mine after loss of roll axis. Sheared at 485hrs. I’ve always felt like my aileron forces were on the excessive side, had hoped over time they would lessen, not the case. Feels like most of the resistance is in the torque tube and torque blocks, as when aileron cables are disconnected forces are pretty close to same. About 4lbs left or right...







Pete Meyer
Severna Park, MD
CCK-1865-0078
N9PW