Before fabricating the forward overhead insert from carbon fiber, I wanted to try it out for ergonomics and for wire routing, so I laser-cut it in cheap acrylic and mounted it on - turns out the screw holes from the CAD model were slightly off, and I need to move the O2 distributors slightly forward:
Overhead console insert mockup
I also tested out the GoPro mounting position, and it gives a nice view:
GoPro's view of the cockpit when attached to the overhead console
Once I removed the pilot's seat, I could finish drilling the stick grip connector hole on that side:
Pilot stick grip connector hole underneath the pilot's seat
One of the last large steps was to embed the TAS antenna ground plane on the cabin cover (and since there's only a small amount of information about this on other blogs/forums, I'll try to be detailed here) - we covered the plane to keep the dust out, and carved it with the Dremel (using the router accessory) to the depth of 2 fiber layers plus the metal:
Airplane covered up for carving the cabin cover
Cabin cover center before carving (with metal tube trimmed flush to it)
Carving the cabin top for the ground plane
Caved cabin cover top after sanding (with ramps at the edges for the fiberglass to bond to)
We then sanded the surface to be as close to flat as possible, added a layer of fiberglass to bond any exposed foam core, and trimmed the center pipe flush with it.
We used a 3D printed jig the same shape as the antenna (by 3D scanning the antenna) for alignment and drilling the antenna attachment holes straight. I included a center slot for alignment with the aircraft's axis, a protrusion that will go into the center tube, holes for drilling the antenna attachment, and some extra margin around the antenna (which will be filled with sealant anyway):
GA58 installation jig
GA58 jig compared to 3D scanned antenna
3D printed GA58 mockup jig
(I added this jig to my Designs folder in case anyone wants it)
The slot at the center helped us perfectly align it with the airplane's centerline using a laser (or it fits a ruler for similar purposes):
Aligning the drilling jig using the laser through the center slot
Laser through the aircraft's centerline, for alignment
Antenna, perfectly aligned at the center thanks to holes drilled through the jig
We then bonded the metal ground plane (which I had already tested before and passed the GTS test), using the same jig to compress it flat against the fiberglass at the center, and clamps and weights around the edges:
Metal ground plane bonded to the cabin cover, with jig holding it flat in place
Metal ground plane bonded to cabin cover, with well-aligned holes
Still using the jig, we scuffed the parts of the ground plane that the jig didn't overlay, and laid 3 more layers of fiberglass to bring the structure as close as possible to the original, while leaving an antenna-shaped section of the metal still exposed for direct contact:
Scuffing the TAS antenna ground plane where it'll be underneath fiberglass
Fiberglass layers on top of the TAS antenna ground plane
We also installed Clickbonds on the wire covers and around the bulkheads to secure wires and the pressure tubes so they avoid the interior cover parts and other screws:
Overhead wires secured to wire cover
Pitot and AoA tubes secured to bulkheads
I received the last part of the Mountain High kit (nevermind that prices more than doubled :( but at least it was just the last kit), with the cylinder, regulator and masks. The regulator they sent with the cylinder is the 2nd generation IPR, which is great, but had some changes from the 1st generation that I had to account for - notably, they changed the emergency O2 switch, from a simple 2-port pneumatic switch to a 4-port one (presumably so it can positively operate the valve in either direction?), which required me to change the switch on the panel, and I'll need to run one additional tube to it:
Old IPR emergency O2 switch installed in place
New IPR emergency O2 switch installed in place
I will only install the cylinder and all tubing once I'm done with all dust-generating work (like fiberglass sanding) and have thoroughly cleaned up the plane, so there's no chance of any dust getting into the system.
Next up is probably sanding/finishing the cabin cover fiberglass and attaching that antenna, after which we can finally finish the overhead wiring and attach the doors and windshield.
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