It’s alive…

Sometimes all those little individual tasks you’re churning on, come together in a moment of progress. Tonight was one of those nights – the battery contactor and avionics relay switches are now active, and the main and avionics busses are connected. It’s time to flip a few switches…

Lots more wiring to do, but motivation is high.

Right side subpanel wiring

Left side sub panel wiring

More wiring in the tail

Even more fun with wiring…working my way forward from the tail I routed serial data and power wires to the ELT and assembled the autopilot pitch servo DSub connector.

AP pitch servo and ELT wiring

I also ran coax to the GTN-650 GPS and G3x GPS/XM antennae.

GPS/XM and light wiring

Assembling coax connectors is fun, at least for me…

GPS/XM antenna connectors

More to follow as I work my way forward to the cockpit.

Wiring from the tail forward

There isn’t a super-convenient way to route pitch trim and magnetometer wires into the empennage, so I improvised…

Here’s the pitch trim servo wire exiting through a lightening hole in the fuse rear deck.

Routing the pitch trim wire

I liberally applied adhesive zip-tie mounts to the rear deck and glued a small piece of aluminum angle to the rear spar with 3M 4000 marine cement (easier than riveting) to hold another zip tie.

Pitch trim wire over the HS sparThe black material is self-closing anti-chafe wire bundling I found at McMaster-Carr. The plans call for running trim wires along the front of the left elevator and into the trim servo bay. I think this is better than running wire through the existing manual trim cable holes as repeated elevator movement over time slightly twists the cable rather than bending it – much better from a wire fatigue/failure perspective.

Routing pitch trim wire into the elevator

You’ll see in this picture how the trim servo cable is routed into the left elevator and why some support is necessary where the cable crosses the HS rear spar.

Pitch trim servo ready for installation

And here’s the wired trim servo ready to be stuffed into the elevator. It’s slightly tricky to route the cable so it doesn’t interfere with the servo’s jack screw, but I think I’ve managed to get everything done correctly.

The nervous system arrives

Back from Thanksgiving with family at Bear Ass Cove on Newfound Lake, New Hampshire and guess what UPS delivered? That’s right – the avionics harness!

Unboxing the avionics harness

I’m almost ready to install the harness – just a couple of empennage things left to finish – but I couldn’t resist stretching it out. This is, essentially, the Mighty RV’s nervous system and having it fabricated by the neurosurgeons at Approach Fast Stack is saving me a *ton* of build time. Cool!

The whole nervous system

Random tasks…

Finally getting a lot of little cleanup tasks done while the avionics harness is percolating at Approach FastStack.

First, I installed this…

Mystery device

First person to guess what it is gets a ThermosWorks sticker or a free beer at Oshkosh 2019.

Second, I dug out the cockpit lights from Oplite and fabricated a small bracket to mount them on the roll bar support.

Oplite 6sOplite wires

These lights are extremely well-made by my friend and fellow RV builder Rich Mileika. In addition to Oplite, Rich owns and operates Machine, Inc, a precision machining company in the greater Boston area. If you need quality cockpit lighting, try Oplite…you’ll like ’em.

And lastly, I replaced the stock Van’s flap motor with an upgraded version made by Pat Hatch at PH Aviation Services.

This motor has several advantages over the stock unit. The motor and jackscrew are separate so grease can’t migrate into the motor windings, a common problem with the Vans motor. It also has limit switches to stop the motor at full extension on either end, and also has a position sensor to report flap position to whatever device needs it.

The only downside is that the flap support bracket must be modified to accommodate the new motor. Rather than trying to rework the existing bracket, I bought new parts from Vans and started from scratch…only took a couple of hours, and Pat’s motor will save some wiring work later on.

Panel population progress

I think it’s time to start mounting stuff in the panel. Being an electronics/avionics geek, I’ve waited for this for a long, long time.

Panel population progressThe white labels are mockups of the panel labels I’m having engraved by Aircraft Engravers in Granby, CT.

The G3x GSU 25 ADAHRS is mounted on the subpanel behind the PFD/MFD – makes plumbing the pitot-static lines to the GSU and G5 a little easier. It was hard to get in there with a ruler to lay out hole positions so I made a drill template out of thin Al.

One minor hiccup…the ignition switch locking tab isn’t clocked correctly, causing interference between the switch body and panel support rib. I’ll probably have to grind off the tab and rivet on a new one at the right orientation. The switch label will cover the rivets nicely.

Switch interference

The light at the end of the tunnel…

…is getting brighter – it’s time to start installing and wiring avionics. I’ve been plotting and planning how to mount the Garmin G3x Touch system, radios and transponders and I’ve settled on building a tray which will hold all the remote-mounted LRUs, Comm 2 and transponder.

Here’s a cardboard mockup.

Avionics tray mockup…and the tray with avionics temporarily attached.

Avionics tray fitting 1The GAD 27 and GAD 29 are on the right side. Most of the airframe power interfaces will be through the right firewall passthrough so having these boxes on the right should make wiring a little more straightforward.

GAD 27 and GAD 29The GEA 24 engine interface is on the left side as most of the engine sensor wires will come through the left firewall passthrough. Guess where the AoA CPU is going?

GEA 24More pics? Sure, I’m glad you asked.

The avionics tray from overhead