Transponder Antenna Mount

Posted on by Neal

Having more-or-less finished the shelving behind the panel, I moved onto the antenna installation. I ordered the antenna I needed from Vans and Stein Air; 2 comm antenna, 2 GPS antenna, and one ADS B antenna.

I started with the ADS B transponder antenna which mounts under the tail. I had already final-sized the holes when I built the tail cone, but I had also primed in and around the holes. I spent time removing the primer to allow the antenna to connect to the ground plane.

With the primer removed I started work on a backing plate. I’m not planning to rivet the backing plate in place, I’ll secure it using just the antenna bolts. This isn’t quite as solid, but I really don’t want to rivet the backing plate in place. Since I can’t prime the parts, and this is at the bottom of the tail, there’s a chance of corrosion in this area. I’d rather be able to quickly replace the backing plate in the event corrosion occurs in this area.

With the plate made, I was able to easily install the antenna myself as access to both the inside and outside at this location is easy. I placed a bead of silicon to seal the gap.

Primer removed from around the holes. Same on the outside.
Drilling holes in what will be the backing plate
The antenna itself
Antenna installed
Inside view looking after, with the cable connected

Shelves etc

Posted on by Neal

After some time off building for work and other events, I was able to get some time in the garage today. I made a cover for the fuse box, as I won’t be using it. It’s also a (hopefully) convenient location to mount the CO detector. I found a template on Vans Air Force, cut it out, drill holes, and countersunk for flush screws. I match drilled holes for the CO detector mount, then primed the cover.

I also rebuilt the bottom shelf on the pilot side, making a much stronger version. I have been iterating on the design several times, but think I have it right this time. I did a test fit with the vertical power unit and the transponder, and it looks good to me.

Passenger side mounts

Posted on by Neal

The last two days I’ve been working on the passenger side shelves for the engine monitor, air data computer, and the satellite receiver.

The box that will hold the engine data and air data computers. They don’t require cooling, so no issues with encasing them in this way
The plate I’m using to stiffen the sub panel and allow the shelf to be positioned exactly where I want it, without worrying about the panel sub-structure (ribs etc).
The units installed in the box. AN-3 bolts will hold these in position. Tape stops drill shavings from getting into the d-sub connectors. I ended up re-orienting the bolts on the bottom so the heads are on top and nuts underneath
Drilling holes in the sub panel
The satellite data receiver, which requires a certain orientation relative to the aircraft direction of travel. This shelf will install behind the sub-panel.
The shelves installed
Another angle of the sub panel
Passenger side with all the components in their final position. Tape is where I need to safety-wire the piano hinge pins
A look at passenger and pilot side shelving

Exhaust Inventory

Posted on by Neal

After being on backorder for several months the FWF Kit’s exhaust package arrived this week. The box was in rough shape, but luckily everything from the inventory was present.

I had a few extra unmarked parts which should be interesting to figure out.

Box on arrival
Open box of exhaust parts
The extra pieces

Standby battery

Posted on by Neal

Tonight I decided where to install the standby battery and made the parts to mount it above the center channel about 3 inches aft of the firewall on the cover panel between the sets of rudder pedals. I made backing plates to reinforce the panel and to hold the nut plates.

It was a pain to work on this panel because the canopy release cable passes through behind the battery, and I can’t remove the panel without undoing work on the canopy release mechanism. So I drilled, deburred and riveted everything with the panel nearly in place, which was awkward.

Location of standby battery. The screws are temporarily holding this in place.

Sub Panel Mounts

Posted on by Neal

Over the last couple of days I’ve been slowly refining the design and construction for the sub panel mounts on the pilot side. The two biggest boxes going in this area are the Vertical Power and Transponder unit. Originally I was planning to orient these horizontally, but when I installed the bank of switches, there isn’t enough room. So I switched the orientation to vertical. This also meant the standby battery wouldn’t fit, so that is going to move somewhere else. Tonight I finished the construction and test fit everything.

Nut plates and piano hinges have been used extensively
The vertical power unit.
Drilling holes in the various panels and hinges
The location of the two piano hinges that hold the boxes in place on the subpanel. The upper hinge has a backing plate on the forward side of the subpanel
Test fitting the frame. While not shown, I made sure the transponder unit fits inside the cage

Sub Panel Mounts

Posted on by Neal

Tonight I worked on making the first mount for the sub-panel. This will house the GTR-20 remote com radio, and the GMA-245R remote audio panel.

Since my last blog post I’ve made multiple revisions to my plans for mounting the hardware. I’m reasonably happy with the final arrangement, and it’s good enough to get started building. I’m sure I’ll decide to change something else, but it’s time to get started making stuff.

Everything went according to plan, and it turned out alright. With no pre-punched or pre-formed parts the whole construction process took a lot longer.

GMA-20 will sit inside this shelf
Nutplates installed, drilling holes
Working on the shelf
The shelf will be connected to the panel and sub-panel via piano hinges. This allows for easy removal if needed for maintenance
Mostly complete shelf. Com radio on the bottom, and remote audio panel on the top

GEA24 mount

Posted on by Neal

Tonight I worked out how I plan to mount the GEA24 box. This will mount directly onto the sub panel, with a doubler on each side to support the nut plates and provide some additional strength. The box itself is not heavy, but with the cables attached it will be heavier. It also needs to be able to withstand repeated +6/-3 G loads without cracking, so I want the mount to be strong.

Space on the forward side of the sub-panel is tight on one side, and open on the other. I made up to backing plates, the drilled, countersunk, and primed them.

Location of the box on the sub-panel. The doubler on the near side will fit between the map-box doubler (the opening on the right), and the rib flange about 25mm to the left
The GEA24 showing the wiring harness attach points, and the doublers
The doublers. These will have nut plates attached and will be pop riveted into position behind the sub-panel

Remote boxes

Posted on by Neal

Tonight I came up with what I believe will be the right placement for the remote components behind the panel. Initially, it looks like everything will fit in with room to install all the necessary wiring harnesses and d-sub connectors. On the left side, I need to determine the orientation of the boxes. I think setting the vertical power and transponder vertically against the sub-panel, with the standby battery sitting on a tray at the bottom of the space will result in the best clearance. However I’ll keep options open and try both.

Now I need to work out the tray structure I need to build to hold these components. I’ve seen a few ideas, but need to settle on a plan.

Right side mock-up. Com radio, remote audio panel, engine monitor, air data receiver, and satellite data receiver. the white tape indicates the approximate location of the canopy frame when closed.
The actual boxes oriented as they will fit in the space. Black box is the satellite receiver, and it has a specific required orientation. It’ll be raised to allow connectors to pass underneath.
Option 1 for left side orientation. This gives the most clearance from the bottom edge of the screen recess. another unknown is how much space I need behind the switches which sit below the screen on this side. I may need to install the switches temporarily to check this out.
Option 2 for the left side. This would be my preferred orientation, but there might be a clearance issue.

Panel test-fit

Posted on by Neal

Tonight I installed the panel inserts and mounted the G3X screens. This is a temporary install to measure distances and clearances behind the panel, and to confirm my suspected lack of clearance between the control stick grips and the panel.

It really starts to look like an airplane cockpit with the screens in place! Unfortunately, as I suspected, the stick grips are just touching the screen bezel in their forward most position. I’ll need to shorten the sticks by approximately 2 inches to allow them to clear the bottom of the panel.

Panel and G3X screens temporarily installed. I didn’t install the G5, G750, autopilot, or switch panels, as the main concern is the space behind these G3X screens
The space where the remote mount modules will be installed. This is the passenger side