Thanks Mike and Nishaunt, this was a tough puzzle.

Cable tensions (checked three times with three different calibrated tensiometers), AP computer swapped multiple times, FD Computer swapped multiple times, VG swapped, Trim actuator inspected twice, Trim Switch wiring repaired, ALT preselect swapped, AP control head swapped, Attitude indicator wiring repaired, ISS analog converter swapped, ADC altimeters swapped, Pitch servo swapped. All swapped units known good.

It will require one more flight test tomorrow, but we have a high degree of confidence that there were 2 pitch squawks occurring simultaneously...the VG and the FD computer. Jet Tech were a big help with this one.

John,

That sucks. At least you know someone to help. Haha and BTW Zach and your guys have been amazing. By for the best shop I have had my plane to yet.

Are you able to test the failure mode on the ground? Or do you have to fly it to have the issue come up?

Mike

No we weren't able to duplicate it on the ground. You could hook up the plane to a GPU and simulate AP procedures (climb, descent, capture, hold) all day with no issues. Manipulate both ADC's, preselect, pitch command, etc. No problem.

It appears that the VG needed an extended climb to fail. The servo and FD computer had an issue that also seemed to require in flight voltages and control surface forces to replicate the issue.

It's interesting to look at Duncan's website and read the 8130's that they include with their FD computers. Not surprisingly, the capacitors and resistors have simply aged out on the many of these Sperry FD and AP boxes. They're not "broken" they just need maintenance after decades of temp cycling and vibration.

IMHO that's going to be the Achilles heel of legacy Citations until we get the Garmin AP....some of these old Sperry components are getting WAY to expensive to overhaul.

John

I agree the AP is the legacy citation weak link. It’s way better than most old AP’s but getting tired.

I thought Garmin would have had the digital AP out by now for CE-500’s

I am sure you guys will figure out your issue. You will learn a lot along the way. Haha.

Mike

I h'reby nameth sir john kennedy the kingdom’s gremlin slayeth'r. Well done sir!

REALLY appreciate that btw.

I would love to have an in-house Sparky that could test AP/FD boxes all day and replace bad components on the boards.

I have found VG issues by lightly tapping on them with the autopilot engaged. When they get noisy pickoffs that will usually show up as the pitch servo going crazy when you lightly tap on the VG. Might have to put it in a typical cruise pitch attitude.

I have found VG issues by lightly tapping on them with the autopilot engaged. When they get noisy pickoffs that will usually show up as the pitch servo going crazy when you lightly tap on the VG. Might have to put it in a typical cruise pitch attitude.

Who do you guys like for in airplane type rating? Do you know of any instructors who will come to you? I have a 3 week old baby at home and my wife isn’t too thrilled at the idea of leaving her with a baby and 3 other kids.

https://fiestadestinationservicesinc.com/

Charles will come to you, do your training in your airplane, and then the two of you will fly your airplane to the DPE for your checkride.

My last 61.58 + SPE was with Dan. Straight up guy.

Mike C.

Can Dan still do in plane SPE?

Mike

Yes.

See attached. He was just renewed this March.

A few instructors were denied renewals. In those cases, they had gotten lax about procedural and paperwork things and the FAA suddenly got strict about checking these things. Dan wasn't among them.

Dan is also both instructor and DPE which helps with logistics.

Mike C.