PerfTech
Well Known Member
.... I am posting this as it may help someone else from the same experience I had last weekend en-route to the Vans Homecoming. We traveled the last 200 miles or so VFR on top with no ground sightings or holes to be had. We were between layers and things were getting worse rapidly when all of a sudden my airplane began a turn to the left for no apparent reason. This is when I became aware that my auto pilot, True-Trac ADI Pilot II, was not functioning. This is where I really needed it and the first and only time it has failed to function perfectly in 600 hrs. The altitude hold was working, all indicator lights were on, but no roll servo action at all. After returning home I went to work locating the problem and found it had sheared off the shear pin in the servo arm. Not a difficult fix, but in retrospect I think I know what caused it to quit. I have on two occasions put considerable stress on the airplane, once in severe turbulence and one high G drop on landing. I am sure this is what stressed the pin and it finely just let go at a very inopportune time. The moral to this story is this, if you have been in extreme turbulence or a hard landing you may want to consider changing these pins. They are very inexpensive and easy to change. This ounce of prevention may save your axx one day. I definitely like a working auto pilot when in the clouds. Thanks, Allan