Schllc Posted November 27, 2022 Report Share Posted November 27, 2022 On 11/4/2022 at 4:35 PM, BravoWhiskey said: Well I did not see this one coming! annual is complete. Hats off to Weber Aircraft and Lancaster Avionics again. The 7 weeks wasn’t their fault because the AP and elec trim was serviced… again! But this time they may have finally found the bug that has been plaguing this system for years. Apparently the computer in the STEC55x was actually for a Cirrus. So now I have an Autopilot and servo that is specific to my airframe… how nice. I did notice some differences in the reaction time and direction today. On the prior system the aircraft would sometimes start the turn in the wrong direction for about 5-10 degrees then correct itself. I’ll play around more tomorrow when I have time to fully test everything out. oh… and about those v-bend clamps… not cheap! I reviewed the log books on your plane a few weeks before you purchased. The main computer for the autopilot had been changed several times, I also noticed the recurring trim problem. I couldn’t help but think those two were related and I saw no resolution or even evidence of diagnostics beyond changing electronic components. If I’m not mistaken Airmart actually had to service the autopilot immediately after they purchased and listed the plane. I suspected an underlying issue and asked them to warranty the repair for a year after purchase to make sure that they fixed the problem and they declined. I hope the correct servo was the root of the problem, but find it hard to believe after all the years and services that this was the issue. That being said, my experience with Weber, as well as their reputation would suggest they are more thorough than most. Quote Link to comment Share on other sites More sharing options...
BravoWhiskey Posted November 27, 2022 Author Report Share Posted November 27, 2022 51 minutes ago, Schllc said: I reviewed the log books on your plane a few weeks before you purchased. The main computer for the autopilot had been changed several times, I also noticed the recurring trim problem. I couldn’t help but think those two were related and I saw no resolution or even evidence of diagnostics beyond changing electronic components. If I’m not mistaken Airmart actually had to service the autopilot immediately after they purchased and listed the plane. I suspected an underlying issue and asked them to warranty the repair for a year after purchase to make sure that they fixed the problem and they declined. I hope the correct servo was the root of the problem, but find it hard to believe after all the years and services that this was the issue. That being said, my experience with Weber, as well as their reputation would suggest they are more thorough than most. It was an actual circuit board within the s55x computer… so because of that the computer was telling the servo to operate a little differently than it should. They believe this was why the amperage draw on the servo was outside it’s normal limitations. It would appear this computer could have been using the wrong board since it came off the factory floor. Serial number for the s55x and servos were always correct though, it was just a wrong board within the s55x. It is kind of disappointing that no one prior to this looked at the issue a little closer, but it is what it is. Weber, Lancaster Avionics and Genysis diagnosed the issue together with the goal of determining why this was occurring instead just replacing. Quote Link to comment Share on other sites More sharing options...
Schllc Posted November 27, 2022 Report Share Posted November 27, 2022 1 hour ago, BravoWhiskey said: It was an actual circuit board within the s55x computer… so because of that the computer was telling the servo to operate a little differently than it should. They believe this was why the amperage draw on the servo was outside it’s normal limitations. It would appear this computer could have been using the wrong board since it came off the factory floor. Serial number for the s55x and servos were always correct though, it was just a wrong board within the s55x. It is kind of disappointing that no one prior to this looked at the issue a little closer, but it is what it is. Weber, Lancaster Avionics and Genysis diagnosed the issue together with the goal of determining why this was occurring instead just replacing. The main AP head was replaced several times with different units. Do you think they just looked at the board type that was returned as a reference, instead of the make and model, each time it was replaced? Is the trim wheel supposed to be stiff when the AP is off? I have only had a few intermittent AP problems on my moonies, and I don't really recall if the trim wheel is stiff when it is off.... Shouldn't the servos go into "neutral" when the power is off? (I am going to fly today and test that btw) I went back to look at the logs that I had (through 2020). There were 12 instances of either computer replacement/overhaul or trim servo replacement/overhaul in 13 years. That really sounds like a mechanical problem causing the electronic failures, but it’s just a quasi educated guess… Either way, the plane was really nice, and had a really high UL for the equipment, which is why it was so tempting. I sure hope this takes care of your gremlins. Quote Link to comment Share on other sites More sharing options...
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