Panel turns on!

I started connecting the coax cables, with the transponder and bottom COM cables first (since they don't require messing with the overhead console):

COM and transponder coax cables running through the subpanel

The GPS antennas had too-short screws that were not going through the nut inserts, so I replaced those with longer ones (turned out MS24693C56 and MS51958-68 were the right lengths):

GPS antenna doubler with screws not coming out

GPS antenna doubler with longer screws


Bottom COM cable connected to the antenna

Transponder cable connected to the antenna

Tailcone ground wires connected

It was then the time we've all (or at least I have) been waiting for - I assembled the panel in place, and started turning on the LRUs one by one (by controlling each output of the VP-X from a laptop):

Panel frame and center section attached in place

Connecting left-side switches to wire harness

Panel turned on in place!

All of the magic smoke stayed inside!
I played a bit with the system and most connections seem to be fine, but of course there's a CAN bus failure which is preventing most LRUs from communicating - my next step will be tracing that down, then finishing up the wiring (still have to do all of the overhead console wiring, baggage light, securing all the wires, and then later the engine sensors).

Time lapse:


Total avionics rivets: 161
Total avionics time: 268.8h

Panel breakout connectors

I put together the left-side breakout connector, which is a mixed power/signal connector (TE CPC series 4). For the 10AWG EFII battery wires (which are the main reason to have this connector, so I can easily disconnect the hot battery wires from the rest of the panel without going into the tailcone), they're supposedly standard open-barrel crimping, but my generic crimp tool from ATS did a pretty horrible job at it, ruining the fancy expensive socket:

Bad crimp on $23 10AWG CPC socket :/

Part of the problem was that the crimp tool "pinched" the corner of the connector as it was compressing. I managed to crimp them properly on the second attempt by trimming the tabs, compressing the sides slightly to make it narrower and not caught on the corner of the tool, and by crimping the insulation first before crimping the wire (which left a small mark on the wire but oh well). With that, and by adding all the signal wires, I completed the left-side CPC:

Completed left-side breakout plug

The Aerosport interior panels have a recess that occupies most of the bottom part of the under-panel sides, so to route wires away from that area, we installed some Click Bond mounts on the sides:

Clickbond fasteners to secure the right-side wires behind the Aerosport panels

Battery cable attached to Clickbond fastener

Left-side wires running through Clickbond fasteners

With that, I could tell the wire lengths for the left breakout receptacle and install pins on those wires. This time, I managed to do a much more decent job with the 10AWG pins on the first try:

EFII/bus manager battery wires pinned for the left-side breakout connector

Completed left side breakout plug and receptacle

Assembled (and quite bulky!) left-side breakout connector

It was then time to finish the right-side breakout connector (for which I had to wait for more snap bushings for the side passthru holes):

Right-side breakout receptacle wiring

Right-side breakout receptacle closed up

Right-side breakout connected

I also transferred the location of the wing conduits to the side of the fuselage to get a sense of wire lengths and where to cut holes for the CPCs:

Wing root wire exit location markings

Next I'll be working on the tunnel and wing root wiring.

Time lapse:


Total avionics rivets: 161
Total avionics time: 259.3h

Avionics connectors progress

I ran that last remaining ground wire (the 14ga pitot heat ground) through the existing bundle, then connected the defrost fan power/ground crossing above the GTN, to be secured above it in some way (probably a Clickbond?) later along with the G5 GPS cable:

Cooling/defrost fans connected (wire over GTN to be secured later)

For the door sensors, I had previously attached Molex SL connectors to them, not realizing that the 18AWG I had ran for it per plans does not fit in the SL series :( so I swapped those for Molex CP series which can do 18AWG and are still fairly small:

Molex SL series (bottom, black) vs CP series (top, green) attached to door sensors

I ran the wire between the sensors on each side, but I'm still waiting to do the side connectors before I trim the other wires:

Molex CP series connector attached to door sensor

To prevent any chafing of wires coming out of the LRUs against the subpanel edge, I paranoidly added some grommet edging to that:

SL1 edge grommet on subpanel edge to prevent chafing

It was then time to finally work on the side connectors - the plan is to replace most DB connectors with a single CPC, and leave only the roll servo connector as is (so I can plug the CAN terminator to it). I started by trimming all wires to roughly the same length, re-pinning them (the TE series 2 CPCs use M39029/63-368 sockets just like the the DB connectors, so for all wires that were on the shortest bundle, no rework was needed), and adding labels which were missing:

Labels for right-side CPC breakout connector

Right-side breakout wires (including longer GTS power pin)

For the few 18AWG wires (the GTR20 and GTS800 power wires), those pins are too small. Stein's install had the GTR wires spliced onto a 20AWG wire just to go through the connector (and I left that in place since it was already the final length), but they had used a large separate Molex connector for the GTS power and ground - instead of doing that, I used the special 18AWG pin/sockets (FC6018D2 / MC6018D), which are a tradeoff - they require no splice, but they extend outside the connector housing and require heatshrink around the extension, plus they're not removable (the way to remove them is to cut them off since there's no way to get the removal tool around the bulkier part of it). I figured that if I ever do need to remove them, I can then add the splice and use a regular pin.

I then finally installed the CPC - the shell was a tight fit but I didn't need to go to the large-size shell as I had feared:

Right-side breakout connector fully pinned and ready to close

Right-side CPC and roll AP connectors closed up

Right-side CPC and roll AP connectors

Next I'll do the same to make the left-side breakout connector (which is much simpler since that's the power connector, but also much more critical as it'll carry power to the EFII system and feed the essential bus).

Time lapse:


Total avionics rivets: 161
Total avionics time: 242.7h

Ground/power wiring finished

I shortened/rerouted the fuse block wire bundle:

Fuse block and door relay wiring

I also finished wiring the VP-X by running all the light and pitot heat wires to the wing root exit points, and changing how Wig-wag is connected - in the old Ziptips they had to be grounded, were 18 AWG wires, and were associated with the landing lights, with the new ones they're 22 AWG wires connected to power and associated with the taxi lights, so I ran the wire out of the taxi light output of the VP-X. 

I then took on the tedious task of labeling the ground wires (which didn't come labeled from Stein) - which meant getting a probe into each device's ground pin, and then using the other to figure out which ground connector it was wired to, and since there were multiple wires per terminal, then cutting off the connector and figuring out which of those wires were for the device:

Tracing ground wires (multiple per terminal) before cutting off the terminals

Labels for all the ground wires

Labels on all the ground wires after tracing them

I also ran ground wires for the devices that didn't have them yet (fuel pumps, door sensors, GHA15, etc.), and then finally trimmed them all to size and attached faston terminals:

All ground wires shortened, labeled and with fast-on terminals

Ground wires connected to the forest of tabs on the firewall

(there's actually one ground wire left to run - the pitot heat ground - because I didn't have any black 14AWG handy - but I can easily slip that one through the existing wax lacing)

I ran the left-side signal wires through the conduit to the tailcone, connected the relay control wires, and attached terminals to the battery fault and hall effect sensor wires. These will get trimmed up front where I insert the breakout connector:

Primary power control wires in place in the tailcone

Next on the wiring, I'll add the side breakout CPC connectors and route the side wires where it doesn't interfere with the Aerosport panels.

Time lapse:


Total avionics rivets: 161
Total avionics time: 231.6h

Avionics rebundling progress

I shortened/moved the IBBS wire bundle (which also needed labeling the wires), the CO detector bundle, and the yaw trim bundle:

Pinning and labeling shortened IBBS wire bundle

Shortened IBBS wire bundle

Original, very long yaw trim relay bundle

Shortened yaw trim relay bundle in place

I also finished the roll servo breakout connector, keeping it as DB15 with the same pinout as the GSA28 itself so that I can directly plug the CAN bus terminator to it:

Roll GSA28 breakout connector with CAN terminator (until the wings are attached)

I then finally wired the EFII display connector and circuit breakers (may still need some cleanup/bundling later):

EFII display and circuit breakers connected to ECUs/power

EFII display and circuit breakers with all wiring in place (still not very organized)

After securing the main bundle to the panel, I wired all the switches:

Left-side switch connectors

and then updated the power connections to reflect both the VP-X bank analysis I mentioned in the previous post and the updates for the Ziptip Vegas (as well as shortening the long bundles):

Shortened left-side VP-X wire bundles

Shortened right-side VP-X wire bundles

VP-X with shortened wire bundles

Unrelated to the wiring, there was a discussion about the 120° clearance cone required for the GHA15, which made me measure it again for my install - it is indeed close to the main gear, but just about clears it - I could increase the clearance a bit by moving the antenna a few inches forward, but that'd require relocating the fuel pumps too (at least moving them up to clear the antenna connector), which I wanted to avoid:

Tip of the GHA15 120° clearance cone near the main gear

Next, I'll finish the power wiring by also shortening the fuse block wires, and all the ground wires (which also need to be labeled, none of them currently are). I decided to not try to shorten the GAD29 wires, but that'll be the only long bundle left. I also need to update some of the light switches for the Vegas ziptips (adding the recognition lights, and moving the wig-wag to the taxi light switch).

With this, I'll be doing the long, tedious work of doing a continuity check on all the in-panel connections (I'll later do the same for the tailcone and overhead connections, once I've finished the breakout connectors) - maybe by the next post I'll be able to turn on some of the avionics again.

Time lapse:


Total avionics rivets: 161
Total avionics time: 211.9h

Engine sensors, System32, GHA15 and more wiring work

I installed the CHT and oil temperature sensors in the engine:

CHT sensors installed in place

Oil temperature sensor with ATM connector

Oil temperature sensor safetied in place

I also finished wiring the System32 (as neatly as I could given its prewired bundles):

Completed ECU wiring in place (bottom view)

Completed ECU wiring in place (side view)

On the main wire bundle, the main challenge with SteinAir making it without having the physical panel is that a lot of the lengths are off - in a couple cases (the GTN bundle and the breakout connectors) it was a bit shorter than I'd like, but in most cases it was too long - like these very generous ground wires and the GEA24 bundle which would hang down onto the copilot's leg:

Super long ground wires I got from Stein, which will need to be trimmed

GEA24 wire bundle hanging down into the copilot leg space

so I shortened the GEA24 by about 8" - luckily, most wires were not connected on the other end so I could just pull them through, but a few others had to be re-pinned. I also realized this is the bundle I'm most likely to make changes to in the future (adding/removing sensors and so on), so I removed the nice-looking sleeving in favor of just wax lacing it:

Shorter GEA24 wire bundle, just wax-laced for ease of future changes

Since I was re-pinning the CAN bus connection to the GEA, I also took the opportunity to add the GHA15 in there, and got started with attaching with its doubler:

Match-drilling the GHA15 doubler in place

GHA15 doubler on the outside for opening up the remaining holes

Yes, the GHA15 is only about 2ft forward of the GA58 antenna, but Garmin doesn't seem very concerned given how far apart the frequencies are (~1GHz at 40W vs 24GHz at 19mW) - worst case, I'll need to adjust positions later by poking more holes into my fuselage. Also, based on the bit of trimming I had to do to the sides of the doubler, I updated the published F360 project so no/little trimming is required.

I also started analyzing the VP-X connections for reliability, and came up with a matrix of what bank I want each device to be on (so a full bank failure leaves me enough on the other bank to keep flying comfortably in IMC). The criteria was:
  • GTN and GNX should be on separate banks (NAV redundancy)
  • GTR and GTN should be on separate banks (COM redundancy)
  • GAD29 should be on the same as the GTN (most useful together)
  • PFD and MFD should be on separate banks (display redundancy)
  • GSU and G5 should be on separate banks (AHRS redundancy)
  • Fans and GTN should be on the same bank (most heat-producing device)
  • GEA and MFD should be on the same bank (most useful together)
  • GMC and GSAs should be on the same bank (most useful together)
  • ALT1 and ALT2 should be on separate banks (alternator redundancy)
  • Landing and recognition lights should be on separate banks (landing light redundancy)
  • IBBS and G5 should be on separate banks (backup battery redundancy)
  • Pitot heat and PFD should be on separate banks (both losing the PFD and getting iced up in IMC would suck)
With that criteria, I came up with a matrix of possibilities (spreadsheet here with a bit of magic in the conditional formatting):


which then let me make the selections:


Next, I'll shorten/move the IBBS wire bundle, wire the EFII display, wire all the switches, and get started on the power wiring updates above.

Time lapse:


Total avionics rivets: 161
Total avionics time: 193.2h