Firewall Passthrough

This weekend I decided it was time to install the firewall passthrough fire-proofing sleeves that secure the wiring bundles. There are two on the RV-14, and on my setup I have the main power cables going through one, and the smaller sensor data cables going through the other.

First I confirmed there was mother else that I’d forgotten to route through the firewall. In an attempt to future-proof the setup, I ran three spare wires through the firewall. Each is long enough to run from any point on the panel to any point in most places in the engine compartment.

I figured out quickly that Vans’ plans could use an update. There’s no way to wrap the bundle of wires with the supplied fire sleeve the way they describe. However, rotating the fire sleeve 90 degrees allows you to cut it to a useful dimension. Once the fire sleeve is pushed through the opening, it’s filled with high temp RTV, then wrapped with a second layer of fire sleeve, and secured with safety wire.

I was happy with how this turned out, especially after reading other reports of a messy and difficult job.

When applying the RTV, I used a flat plastic bag (a cake decorating bag) with a small opening. This helped to get the RTV down into the tight spaces between wires, and allowed me to attack it from both sides of the wire wall.

First layer of fire sleeve in place and filled with RTV. The black protective wiring sleeves terminate right at the edge of the RTV mess, and can be removed if necessary.
Second layer in place and secured.

Control stick connectors

Today I installed new Deutch connectors on the control stick wiring. This is my third attempt to wire the sticks up, the previous two were either too bulky, or too insecure. the deutch connectors have a nice backshell that holds d-sub pins and keeps the pins in perfect alignment. The backshells have a sturdy latch, and can be fairly easily mounted.

I cut off the molex bracket from the control stick bases. This allowed the new connectors to sit close to the control stick, minimizing the potential interference. I installed the deutch d-sub pins, and then mounted the connectors.

I installed the passenger side to check clearances, and then replicated for the pilot side. I won’t install the pilot side sticker just yet as I’m going to be working under the panel next.

The last step was to glue the mount onto the stick base with some epoxy glue. I roughed up the mount’s surface, and the powder coating on the stick base before glueing the mount’s surface on.

One half of the connector. The orange colored insets hold the pins in just the right alignment. I should have used these things for all the aircraft connectors, they are awesome.
Mount glued onto the right (passenger side) stick
Connectors wired and installed onto the mount. Supported by a padded zip tie
Some more padded zip ties secure the wires and prevent any movement

Elevator fairings

Over the last couple of weeks, Dad and I worked on the elevator and horizontal stabilizer fairings. Dad spent a lot of time getting the fairings to fit just right: trimming, glueing/glassing, sanding, and repeat. These fairings fit very well, and the gap between the HS and Elevator fairing is exactly where it should be. Dad was able to add a little curve to the aft edge of the HS fairing, which allows for a constant gap between the forward edge of the elevator fairing and the HS fairing, throughout the full range of elevator travel.

We also spent time sealing the area around the counterweight on the inside of the elevator tip, leaving one small exit hole on the aft end for draining any water that makes it into the elevator tip. Hopefully the sealant will keep any water penetration to a minimum.

Despite Dad’s near perfect fairing between the aluminum and fiberglass, once I started riveting the fairings, the rivets introduced a little bit of pillowing. It’ll need one more pass to fair it out before it’s final painted.

Test fitting the Horizontal Stabilizer fairings
Adding some curve to the aft edge of the HS fairing. The dowels are temporary to hold pressure on the structure
Finalizing the elevator/HS gap
Primed and ready to be riveted
Finished.

Wheel Pants

My parents were visiting for the month of July, and during that time, Dad and I worked on the wheel pants. These turned out to be rather time consuming, and having Dad’s help was amazing. As a boat builder by trade, Dad’s an expert at working with fiberglass, amongst many other skills. The quality of his work and attention to detail are second only to his work ethic. Despite turning 80 this year, Dad was working in the garage from 7am until 10pm each day. He was working up until the last minute, and managed to see the wheel pants through to completion. Thanks Dad!!

I didn’t realize how long the wheel pants section was in the Vans instructions. Part of it is the details they provide on each step to prepare and finish the fiberglass parts. Despite the length of the instructions, we found there were some things missing that would have been super helpful. For example, some dimensions of how the pants should sit, relative to a level ground, would have allowed us to verify placement, before final drilling the pants.

A lot of the work involved fitting and finishing the pants, the gear leg fairings, and the upper and lower gap fairings. Lots of filling and sanding to get things to line up correctly and to fair out the transitions between parts.

In hindsight, it might have been worth looking at some 3rd party wheel pants, just to save some time. I’m happy with how the parts turned out, although I’m sure there will be a little more work before they are ready to be painted.

After mum and dad left, I painted the parts with Stuart Systems Ecoprime, a two part epoxy primer.

Trimming the various fiberglass fairings
After the initial attempt to install hinges in the gear leg fairings didn’t work out, Dad used some 2×4 to glue the hinges into position before riveting. This resulted in a much better finish.
Initial test fit to locate the wheel pants
Locating the wheel pants onto the brackets which mount to the wheel assembly
Locating the wheel pants
Test fitting the gear leg and upper gap fairings
Test fitting the gear leg fairing and upper gap fairings
Some of the fairings had been repaired by Vans, including the edge of this fairing that was repaired with filler, which cracked and fell out. Dad cleaned this up and added some fiberglass for strength
Some of the fairings had been repaired by Vans, including the edge of this fairing that was repaired with filler, which cracked and fell out. Dad cleaned this up and added some fiberglass for strength
Attempting to get the correct angle for the wheel pants prior to final drilling holes.
Installing nutplates on the wheel pants
Test fitting the wheel pants after installing nutplates
Fitting the upper gap fairings. These needed some sanding, glassing, and filling to get a tight fit on the cowling
Fairing the transition between the wheel pants and the lower gap fairings
Fairing the transition between fore and aft halves of the wheel pants.
Glassing up the aft flange of the upper gap fairings. Peel ply helps remove some excess resin and allowed me to clamp the glass down
Before trimming the aft fiberglass flange on the upper gap fairings
Two overlapping fiberglass flanges help to stabilize the trailing edge of the upper gap fairings
Final fitting of the right wheel pants prior to removing, installing nutplates on the cowling, and then painting these parts.
Parts removed and primed. Note the tail fairing also received some paint

Rear Window Install

I’d been delaying installing the rear window as long as possible, because access to the baggage area is much easier without it in place. But with Dad here, and with the list of tasks shortening up, it was time to get it done.

We started by carefully masking the window per the Vans plans. We also added some tape to the window to allow us to paint a thin stripe of dark grey on the canopy to obscure the tank sealant.

For paint, I used Stuart Systems Ecopoxy, and brushed it on. It took a couple of coats of paint, but the result was good. With the paint dry, we proceeded to mix up the tank sealant, find all the required hardware, and then start the process.

Rather than following the Vans plans exactly, I took the advice from Ken’s blog (https://vansrv14project.uk), which worked out well. Using a cake decorating plastic bag I was able to easily place the sealant exactly where it was needed. Once the sealant had been squeezed into the gap, we installed the screws and nuts. Dad worked on the outside while I sat I. The baggage area and torqued up the nuts.

Once the task was complete, we let the window sit for an hour, then carefully inspected it, and then removed all the tape. some of the sealant had squeezed out, but it was a tidy job overall.

Rather than just using silicone on the screws along the leading edge, I took the time to seal the leading edge with silicone. I really don’t want the window to leak, and without any kind of sealant, I’m sure water would easily make its way into the baggage compartment.

Painting the edge of the window
Window paint
Window in position
Dad worked on the outside while I sat in the baggage compartment
With the tape removed, the finish looked great
The grey paint hides the tank sealant
The finished product

Tail Fairings

With Dad’s help over the last few days we fit the tail fairings. This required some filling and sanding of the fiberglass fairing that fits between the VS and HS, as well as trimming an d fitting two aluminum fairings on each side, under the HS.

Part of the fitting process involved locating holes in the fiberglass to line up with the nutplates in the aft fuselage. Dad painstakingly measured the location of the holes before drilling them, ending up with a perfect fit.

I primed the parts alongside some of the other fiberglass fairings, and these are good to go now.

Keeping some tension on with a length of rope
Drilling holes
Drilling holes
Final drilling holes in the fuselage, HS and VS. installed some nutplates as well
Starting the sanding
Sanding complete, ready for paint
Inside of the fairing showing some of the filling that was needed to ensure a perfect fit

Steps

Today I installed the steps. I had a local plating shop give these a black matte powdercoat, and then stuck some peel-and-stick grip tape on as an anti-slip. It looks great! I don’t know what the eventual paint scheme will be, but the black matte should go with just about everything.

Installing the steps was fairly straightforward. Without the rear window in, I could stand on the ground and reach through the rear window frame and access the bolts. It took a universal adapter on the socket to torque the bottom nut, but otherwise access wasn’t an issue. I was happy with the snug fit, as these will undergo regular torque changes as people climb aboard, and any movement would be a problem.

Interior Install

Over the last couple of weeks I’ve been working on installing the interior. This is a kit from Classic Aero, and everything is well designed and manufactured.

There are a number of holes to be drilled, fittings to install, and a few minor adjustments. The kit comes with a set of templates which make locating the holes a non-issue. Once the fittings are installed, the various components can be fitted into position. Most attach with simple studs and bolts, and some pop rivets here and there.

This wasn’t weeks worth of work, but chipping away in the evenings, I spent around 8-10 hours in total.

With everything installed, the interior looks amazing. Unfortunately I have to uninstall most of it so I can complete the wing attach, so after verifying I had all the right parts, and that the fit correctly, a lot of the components came right back out again.

I’m glad I tackled this now, because I found that the seatbelts were not in the kit. A quick email exchange with Classic Aero, and they confirmed they had forgotten to order the seatbelts. The placed the order, and they should be here in 3-4 weeks.

Drilling holes
One of the fittings
One of the fittings
Some of the fittings
Two studs, with VHB tape holding them in place
The aft baggage bulkhead cover needs modification to allow carpet to be installed on the bottom section of the bulkhead. Here I am riveting the Classic Aero section to the cover,
The JD Air latch fits, but needs a modification to flip the spring to the top of the mechanism. I forgot why I circled the holes in red…
I had to replace the Vans 12V adapter plate with a custom one that comes in the kit. There is a plastic ring that covers the edges of the carpet here.
Seats look great!
Baggage compartment
Seats and baggage compartment
Note the forward pockets visible in this picture.

Elevator counterweights

Today I torqued up the elevator counterweight bolts and used JB Weld to secure the nuts in place. This would allow me to remove the bolts (only one at a time), if necessary in the future. The problem with the original design is that the nuts are inaccessible under the elevator fairing which will be riveted into place. By gluing the nuts onto the lead weights, the bolts can be removed and reinstalled, and hopefully fully torqued, without needing to remove the fiberglass fairing.

Right elevator, showing the onboard counterweight, and the bolt heads that will be visible
Left elevator, inboard counterweight
Right elevator, outboard counterweight. This will eventually be covered by a fiberglass fairing. I may seal up the edges of the weight here to prevent any water from seeping through
Left elevator outboard counterweight
Left elevator with JB Weld applied to glue the self locking nut and washer into place. I smeared Boelube on the bolt threads before applying the glue in case any got onto the threads
Right elevator with JB Weld applied
Left elevator tip. This whole area is covered with a fairing
Right elevator tip

	

Pitot Static Check

Tonight I checked another item off the to-do list by testing the pitot and static lines for leaks. Good news – both the pitot and static lines were leak-free. I wasn’t able to test the AOA lines, but will have to do that sometime down the road.

I started with the pitot line. By removing the pilot seat floor panel, I could access the ports where the pitot and AOA lines will connect once the wings are attached. I used a piece of flexible tube, and attached one end to the Pitot connector. I gently blew into the other end until the airspeed registered, and then folded over the tube and held it for a minute. The airspeed indications on the G3X and the G5 held steady for a minute, which met the standard.

Flexible tube plugged into the Pitot connector under the pilot’s seat
Airspeed indication holding steady at 146 knots

For the static line test, I ended up taping over the static ports, then disconnecting the G3X static line where it joins a t-connector. Using the flexible tube again, except this time gently sucking air, I was able to demonstrate steady altitude on the G5 for over a minute. I guess there’s a small chance of a leak between the t-connector and the G3X, but at least I know the G5 has no leaks.

Altitude holding steady at 5000 feet
Squeezing the tube sealed the end well enough to conduct the test