Avionics Installation Question

[whiskytango]

Back in the beginning of 2022 I had 2 G5s and a 3 servo GFC500 installed.  The existing Century 31 autopilot, HSI and Attitude indicator, plus the vacuum system were removed.  My question is: Would the work described above require that the interior panels on the pilot's side be removed?  The reason I ask is that at the end of a flight yesterday, while taxiing to my shade port, I reached over to open the door and get some ventilation going.  To my amazement, my shoulder harness fell off its attachment point to the structure of the aircraft.  I later found the attachment bolt lying on the floor behind my seat.  It would be necessary to remove this bolt and the shoulder harness if a technician needed to remove the pilot's side interior panels to route cables etc.  I checked the bolt and there is no sign of thread stripping or deformation - it seems to have simply backed out under no-load conditions.  Fortunately I have not been in any situation where I needed my shoulder harness, but this could have made the difference between injury/death or not in an accident.  I checked and the shoulder harness attachment bolt on the passenger side was tight.

[PT20J]

Yes, Mooney runs all the electrical wiring along the left side of the cockpit behind the trim panels. 

[whiskytango]

Well I guess this means that the post-maintenance preflight checklist now has to include "Check security of left side Shoulder Harness attachment bolt".  Thanks @PT20J

[StevenL757]

22 minutes ago, whiskytango said:

Back in the beginning of 2022 I had 2 G5s and a 3 servo GFC500 installed.  The existing Century 31 autopilot, HSI and Attitude indicator, plus the vacuum system were removed.  My question is: Would the work described above require that the interior panels on the pilot's side be removed?  The reason I ask is that at the end of a flight yesterday, while taxiing to my shade port, I reached over to open the door and get some ventilation going.  To my amazement, my shoulder harness fell off its attachment point to the structure of the aircraft.  I later found the attachment bolt lying on the floor behind my seat.  It would be necessary to remove this bolt and the shoulder harness if a technician needed to remove the pilot's side interior panels to route cables etc.  I checked the bolt and there is no sign of thread stripping or deformation - it seems to have simply backed out under no-load conditions.  Fortunately I have not been in any situation where I needed my shoulder harness, but this could have made the difference between injury/death or not in an accident.  I checked and the shoulder harness attachment bolt on the passenger side was tight.

Yes…as Skip @PT20J indicated, that whole side of the aircraft needs to be removed.  I’ve been through it several times on my Ovation for various pieces of work, and it’s never a fun task.  Not the worst task, but not fun either.  I’ve always made a habit of removing the interior and reinstalling it myself after every avionics job to ensure it is replaced correctly.  It’s pretty apparent when someone forgets to replace seat belt anchor bolts, so the shop should’ve caught this.  It’s possible they screwed the bolts in just to get them started, got sidetracked, and then never double-checked their security.  Replacing the interior yourself helps eliminate things like this…assuming you know what you’re doing.

[PT20J]

4 hours ago, StevenL757 said:

Yes…as Skip @PT20J indicated, that whole side of the aircraft needs to be removed.  I’ve been through it several times on my Ovation for various pieces of work, and it’s never a fun task.  Not the worst task, but not fun either.  I’ve always made a habit of removing the interior and reinstalling it myself after every avionics job to ensure it is replaced correctly.  It’s pretty apparent when someone forgets to replace seat belt anchor bolts, so the shop should’ve caught this.  It’s possible they screwed the bolts in just to get them started, got sidetracked, and then never double-checked their security.  Replacing the interior yourself helps eliminate things like this…assuming you know what you’re doing.

I removed and replaced it myself when I did the panel upgrade. It takes a surprisingly long time to do it correctly and I didn't really want to pay shop rates for that. Plus, it gave me an opportunity to fix a couple of cracks.

[Fly Boomer]

1 minute ago, PT20J said:

I removed and replaced it myself when I did the panel upgrade.

have you replaced the fasteners with that zippy new 3M "grabber" stuff?  Saw a post here somewhere.  Looked cool.

[PT20J]

1 minute ago, Fly Boomer said:

have you replaced the fasteners with that zippy new 3M "grabber" stuff?  Saw a post here somewhere.  Looked cool.

No, but I did tape Tinnermans on the back of the carpeted side panels where the screws go through them so that the screws don't pull out. I also did that on other places where Mooney just had sheet metal screws screwing into plastic -- for instance the covers over the overhead lights.

Skip