Wiring: Wing root wiring.

Because I chose to do all the wiring myself (to save money and to support my unique avionics setup as shown on my panel), I was responsible for determining my routing scheme.  As this post outlines, from 15-Aug-16, the wiring in my wings include support for a number of functions.  Here is my wiring map for the wings.

I needed a lot more wires than what the stock setup accommodates.

• My optical low fuel level sensors and capacitive fuel senders needed to have their wires come from the front of the spar to the back. 
• My landing lights require a lot of wires, as compared what the Van's suggested lights uses. 
• Though I don't plan to install it, I wanted accommodations for electric roll trim should I decide to install it in the future.
• The right wing autopilot roll servo needed an additional Molex connector added to the right wing's W-1029A-R Torque Tube Support Bracket because there wasn't enough space on the included W-1029D-R spacer.

Here is a picture showing the additional spacer I added to the right Torque Tube Support Bracket showing the Molex connector placed (upside down!), prior to final wiring.  I fabricated the spacer with some scrap and riveted it in to the Support Bracket with two rivets.

As noted above, the optical low fuel level sensors and capacitive fuel senders needed to have their wires come from the front of the spar to the back.  They cannot be routed through the spar as-is.  I could have drilled a hole in the webbing and passed them through a grommet from there, but I didn't want to mess with the structural integrity on a part as important as the spar.  So I routed the wires in the space between the T-00001-L/R Fuel Tank Skin and the spar web, as shown below.  I first injected sealant in the space, tucked the wires in, then locked them in place with a fillet of more sealant.  This approach will prevent the wires from moving and chaffing in that spot.

The left image shows the wires passing under the spar on the left wing.  The left image shows the wires from the optical low fuel level sensor and from the capacitive fuel sender just tacked to the tank rib with sealant on the right wing.

The final wiring setup on the right wing (top image) and left wing (bottom image).

Avionics: The big master wiring post.

It turns out that it's difficult to find pictures of how folks wired their airplanes.  Based on my experience wiring an airplane for the first time, I think I understand why folks tend not to share their work.  One of the goals for my blog was to share all of my work, no matter the quality.  So, though I'm not proud of my wiring work, this post discloses it fully.

I opted to do the wiring myself after learning that the cost to have it done professionally would be between $3k and $5k.  My time tracking spreadsheet shows I spent 220.14 hours on avionics (wiring and mounting).  That's under-reported.  It's probably in the 300 hour range.

Wiring planning began in December of 2015.  Physical wiring began in February of 2016 and continued in fits and spurts until April of 2017.

Here are the posts outlining my harness construction and wiring routings.

• Air frame harness.
• Avionics stack (Garmin and GRT) harnesses.
• Control column harnesses.
• GRT EIS sensor distribution board.
• Canopy harness.
• Fuse block construction and layout.
• EGT and CHT wiring. 
• LEMO wiring.
• Magneto wiring.
• Starter switch wiring.
• Landing light wiring.
• Switch control circuit board for landing and nav/strobe lights.
• Indicator lights circuit board.
• Wing root wiring

Here is a high level electrical diagram for the airframe.  You can read about my topology here.

Bringing the harnesses into the airframe is a gentle affair.  The wire ends are then temporarily labeled so that pins can be later added.

It gets really messy inside, especially at the outset.

Routing wires down the tunnel.

I used wire tie mounts to fasten down the wires adjacent to the fuel pump.  These are from Panduit and are shown on the left.  Some folks use Adel clamps.  Those "nut launchers" are evil, so I wanted to avoid using them, especially in a confined space.  The right image shows how the wire tie mounts were attached to the F-14103 Fuel Pump Brackets with nutplates and #8 screws.  I used four wire tie mounts (not shown), two on each side.

Wires going outboard from center under the seat pans (left is left, right is right).

The harnesses to the wings are set outside the airframe.  Visible on the right image is a temporary min-harness I made to test my landing and nav/strobe lights.

When connecting pins, I used the rungs on my ladder as shelves to hold my various tools.  Nearly every wire was labeled on both ends.  Go to the end of this post to see how I labeled my wires.

Final layout of airframe and tail harnesses going down the baggage area.

The top images show the left side LEMO connector wiring whilst the bottom shows the right side.  I wanted a large service loop on each.  You can also see that I put on little Molex connectors to accommodate later replacement of the LEMO socket.  This whole approach is detailed in this post.

Canopy harness, detailed in this post.

The left side behind the panel, detailing the GRT AHRS and EIS.  Go here for details on the AHRS mounting and here for details on the EIS mounting.

The right side behind the panel detailing the SkyRadar DX, whose installation is detailed here.  You can see the main ground lug at the bottom of the picture.  It just goes into a nutplate on the firewall with an AN3 bolt.

The center behind the panel.  It looks hideous and it is.  However, those wire bundles are so incredibly stout that I'm entirely confident they will not move appreciably during flight.  Also, you can see the MAP sensor on the right side of the plane (left side of image).  It's the black box fastened to the F-01456-R Fwd Fuse Rib.   Details of the MAP install are found here.

A larger-picture view of the entire area behind the panel.



Left side of subpanel.  I plan to spiral wrap the wires along the TruTrak ADI2.

Right side of subpanel.  As an aside, the instrument on the bottom left of the image is my lift reserve indicator (LRI).  Go here to read about an LRI.  A forthcoming post will provide additional details on what I ultimately did to construct my LRI.  Until that time, I'll record here that I used a Manostar FR51AHV-500D differential pressure gauge.

A closer shot of the right side subpanel showing the main ground distribution bus, AE Fuel Guardian and SSR for Avionics Bus 2.

Center of subpanel.

Wider shot of subpanel.

Canopy underside showing the LED strip and defrost fans.  Canopy wiring is detailed here.

CHT and EGT wire routing along engine mount.  This process was detailed here.

The GRT pitch servo.  This was taken prior to replacement of the DB9 hood (explained below).

I replaced all hoods with ones that can be finger tightened (DB9 and DB25).  These were to the AHRS, MAP sensor, GRT HXr EFISs, TruTrak ADI2 and pitch/roll servos.  This allows easier work to be done because I didn't have to use a screw driver.

ELT.  Details of its installation are here.  Just need to route the wires.  I'm waiting for the tail to be mounted to be sure they are routed correctly.

ELT antenna coax running on left side of baggage area.  I used silicone and edge grommets to lock it into place to avoid chaffing.

Wire routing on left side of tailcone.

Here is the magnetometer.  Details of its mounting are here.

Some additional thoughts:

• I did not plan my wiring well at all.  I just routed wires as I went along, so I didn't plan things ahead of time.  
• If I were to do this again (ha!), I would plan accordingly so as to have a much nicer wiring layout.  
• I would add service loops and consider better positioning of the various constituents.  
• I would use the "forest of tabs" approach for the ground bus and leave extra tabs for later additions.
• I would leave accommodations to power additional, future components.

However ugly as it is, I'm confident that my wiring is stout, resilient and ready for flight.  It just could have been a lot nicer.

Avionics: Canopy harness, switch and fan wiring.

The canopy harness has been created and installed.

First, I had to fish the canopy switch wire down the C-01409-L Aft Canopy Rail.  That took a few hours of frustration.  I used some safety wire (top left) and pushed it through the channel (top right).  Then got it through the hole on the forward side (bottom left) and used it to pull through the canopy switch wire (bottom right).

Rather than fish two wires (switch and GND), I grounded the switch to the screw holding the C-01424 Canopy Pin Block.

Then I installed the LED strip under the glareshield, making sure that it was centered along its length and that it was recessed far enough back.  I used the entire 35" length of the stip.  I did not cut it.

Next I installed the ES-00056 CPU Fans (defrost fans) and their wiring.  I wanted to preserve the connectors on the fans in case the latter needed to be replaced in the future.  So I bought some cheap floppy drive power cables off of eBay to connect to the fans.

Then I designed the harness.  The Molex connector on the airframe is shown on the left.  It accommodates the wires going to the 2 channel dimmer and provides power to the indicator stack, both from the fuse block.  It also accepts the canopy switch wire for the indicator and the power output from the panel's defrost switch.  Finally, it includes a jumper to provide ground to the fans.  The ground connection is taken from a nearby hole in the subpanel (this is one of only a very few grounds not take from the central ground block).

The Molex connector coming from the canopy is shown on the right.  It accommodates the wires coming from the LED strip, canopy switch and defrost fans.  It also does double duty and acts as a set of jumpers to distribute power and ground to the wires coming from the mating Molex.

Here is the installed canopy harness.

Underside of canopy showing the LED strip and defrost fans.