Bill,

I have read your thread all the way through, and although I don't have a definate solution, I'd like to pass along some thoughts;

Way back when I was still using Futaba gear I tried using some JR 8411 servos with a Futaba PPM receiver and transmitter. I don't recall the model number of the receiver, but it was not possible at all to use the JR servos with the Futaba (ppm) receiver. Glitched all over the place. This has happened with a few other people in the past, but it is and was not a common problem. Since I wanted to use digital servos all the time I switched over to JR equipment only because at the time JR had a larger selection of servos compatible with what I wanted to do.

OTH, I lost a brand new Edge to a new 5945 servo when it went nuts on the third flight (total time on the servo less than 20 minutes), bouncing as fast as it could go from end to end of high rate travels. I just wasn't good enough to keep up with the darn thing. Later I probably would have lost a brand new Extra on the first flight to another brand new 5945 if it had waited to lock up until after the plane took off. As it was the problem was caught on the ground. By no means should this be interpreted to mean that alll 5945 servos are bad. I still believe that may have been a issue with a quite a few back then, but doubt that the issue continues today.

Personally, I use a PPM receiver to set up a plane, and when any and all issues are located and corrected I then install a PCM receiver for flight to provide better outside interference rejection. Setting up using only PCM has the ability to mask problems that would be found immediately with a PPM receiver, later causing a crash when the problem that had been masked becomes strong enough not to be rejected. I set all my fail safes to neutral except the throttle, which is set to fail safe to a high idle. The decision to use PPM or PCM is personal one and can be influenced by several factors. The ultimate choice has to be made by the individual based upon what they like or dislike about either one.

It's entirely possible that a PCM receiver may have been able to reject some of the glitching, and that some of it may have been strong enough to pass through, ultimately causing the crash of your plane.

Pat