New Avionics - How the project evolved...

Nice work.

When I purchased the 'coupe, the panel was partially disassembled. I knew it wouldn't be too difficult to put it back together well enough to fly, but I also knew that I'd want to do some more serious work on it in the future.


ABOVE: As purchased. There was also an old RT-459A Mode C transponder sitting on the hat shelf. 

First all, the AV-30 had to go. The previous owner had installed the "Experimental" version so it wasn't legal.

I moved the COMM radio and Transponder to the bottom of the rack, which freed up enough space to stick in a mount for an Aera 660 GPS.

I replaced a lot of little stuff like fuse holders, pitot-static tubing, and worn wiring - but all in all this setup got me through the annual and a few months of flying. But then... the old transponder died on me.

The dead transponder brought me around to the idea of getting rid of that extended avionics shell. Eventually I wanted a less obstructed panel, but I also didn't want to sling a radio/transponder under the panel because I'm already cramped for legroom.

 

 

Not to mention that some of the instrument installations had been bugging me. Someone had mounted  a bunch of them with their flanges and adapters on the front of the panel.

I decided to install a Trig remote transponder so that installation depth wouldn't be an issue. Unfortunately I'll also need a remote COMM if I want to get rid of the extension rack. Since I wanted to do this in the future anyway, I decided to bite the bullet, buy both Trig units, and start taking things apart. 

 

Someone had hacked an extremely rough opening for that extended rack. The photo above shows the results of a lot of filing and sanding to make it look less alarming. The mounting holes for the throttle, carb heat, and mixture controls were really butchered, so I cut a strip of .063 aluminum and riveted it over the existing holes.

Nut plates were installed around the perimeter of the main opening. I cut another piece of .063 and then the real fun began. You see, the Trig transponder and Comm heads come in a very compact shape that requires an odd cutout shape. To be fair, they include adapters to make them fit a standard 2.25" instrument hole, but I wanted to try to do without them. A lot of cutting and filing later, then trashing the panel and starting over with more cutting and filing...

 

I also decided to install PTT switches where I can press it with my hand on the throttle. All the loose wire and velcro hanging off the wheel was getting me down.

 

Built a tray to install the main units under the pilot's seat. Wiring has been cleaned up since I took this photo.

 

At this point I'm in for a penny, in for a pound and the last things I wanted were fuel flow, and a 4-point EGT/CHT. Removed the old single-point EGT and CHT and did some rearranging.

 

Moved the altimeter to the upper right where it's easier to see and adjust, then moved the MAP gauge into the lower left empty slot. Also moved the parking brake up to the panel so I no longer have a bracket banging my knees. Ground run shows everything working just fine, so now I'm waiting for my A&P to stop by to do one more inspection. Oh, and reinstall the compass deviation card!