Preparing the door mechanisms

I started getting the Aerosport handle and the PlaneAround center latch, by cutting the racks in half, then test-fitting all the parts together:

Door lock racks cut in half

Door lock mechanism on the workbench

Door lock mechanism mounted into the door

From the position above, I trimmed the forward and aft pushrods leaving only a couple inches sticking out in the "closed" position, then safety-wired the parts together:

Door lock pushrods and racks safetied together

We then attached the reinforcement blocks around the center latch position:

Center latch reinforcement blocks glued in place

As the last thing before joining the door shells, I decided to add the iflyrv10 door pull strap, so I made doublers for those. The included mounting hardware is kind of useless - they're very long 1/4" screws and nuts, which I wouldn't want inside the door). so I instead used nutplates for #10 screws (the AN520 series has the same head size as the socket screws they included). I attached them (using the same method as for the gas strut attach doublers) to the top-center of the aft part of the door, which will allow us to easily pull the door closed from the ground (without climbing on the wing just for that):

iflyrv10 door pull attachment block and backing doublers

Door pull doubler match-drilled to the door shell and ready to rivet

Door pull block in place over the door pull doubler

Door pull doublers with primer and nutplates

Door pull doubler epoxied in place

Door pull holes, as seen from the inside

Next, there'll be some more sanding to do (e.g. around the reinforcement blocks), and then we'll join the door shells.

Time lapse:


Total cabin door rivets: 32
Total cabin door time: 48.2h

Door and latch hole drilling

I got back to working on the doors, starting with trimming the handle levers a bit more for a better fit, priming, painting, then assembling the handles:

Door handle parts attached together

I then started match-drilling the fuselage and the doors (at least in parts where I hadn't sanded it down beyond the holes - oops):

Door match-drilled to fuselage

Hole where i had trimmed the door too far to match-drill

Door clamped firmly in place for match-drilling the window frame

Window frame match-drilled between door shells

I also finally (after about 4 months) received the Aerosport low-profile handle, so it was time to start thinking of the latch mechanism - starting with drilling the holes for it. I wanted to avoid actually drilling through the door towards the exterior until the halves are joined, so I "aimed" the best I could using the backing plate and other parts, and opened those holes - expanding them later should be easy if needed:

Aligning latch rack for drilling holes

Aligning latch racks for drilling holes

Latch rack holes drilled into inner door shell

Trying out mounting the door latch racks/gear to adjust gaps around racks

I also opened up the slots for the center latch. I had originally planned to install it through just a single hole for the axis, but decided it was not worth the complication (I could end up with epoxy in the gears, might someday need to remove them, would have trouble with the screws being too close to edges, etc.), so I opened up the slots per instructions:

Match-drilling center latch holes to door inner shell

Center latch attached in place

Next I want to finish getting the latch mechanism ready (as much as I can before the door halves are joined), and then join them.

Time lapse:


Total cabin door rivets: 20
Total cabin door time: 39.9h

Empennage fairing riveting and filling/sanding

I continued the work on the empennage fairing by drilling the nutplate holes for its screws:

Vertical and horizontal stabilizer nutplate holes

Vertical and horizontal stabilizer nutplate holes

Unfortunately, most of those holes actually were on or very close to the flange flutes. I was afraid that a solid rivet would expand in that space, and didn't want to flatten the flute, so instead of dimpling and riveting with solid rivets, I machine-countersunk and used CCR264 nutplate blind rivets, which worked out well:

Vertical stabilizer nutplate holes overlapping the flutes

Vertical stabilizer nutplates attached with CCR264s

Vertical stabilizer fairing nutplate holes attached

On the horizontal stabilizer, I did dimple and use solid rivets (except for two holes which were too close to the edges of the rib flanges, so I countersunk those):

Horizontal stabilizer fairing nutplates attached

We continued the sand-fill-repeat process on the bottom rudder fairing, and got a lot closer to a good finish:

Bottom rudder fairing with primer applied to spot pinholes

At this point, we, of course, sanded it again as several pinholes became evident - and squeegeed another layer of resin with some flox in:

Bottom rudder fairing trailing edge after another layer of resin

We laid up some epoxy and flox around the elevator fairings to make a smooth transition:

Forward face of the elevator fairing filled with resin/flox (unsanded)

Gap between fairing and elevator filled with resin/flox (unsanded)

After that comes a lot of sanding to make a smooth transition on all of them. So far we only did the forward faces, and even those still need a lot of pinhole filling:

Forward face of left elevator fairing, before filling pinholes

Forward face of right elevator fairing, before filling pinholes

Time lapse:


Total empennage fairing rivets: 44 
Total empennage fairing time: 49.5h

Door riveting and sanding

We final-attached the gas strut attach doublers in place, with both epoxy and rivets:

Applying epoxy (with cab-o-sil) to gas strut attach doublers

Epoxying the gas strut attach doublers in place

Gas strut attach doubler rivets

We then sanded all the door shell inner contact surfaces (where the two shell halves touch), as well as the cabin cover flange to let the doors sit flush. In one place, we sanded too much and had to fix it with more fiber:

Door shell corner where we sanded too much

Laying up fiber where we sanded too much

Fiber laid up where we sanded too much

Next is, of course, more sanding :) and getting the doors shell halves drilled together in place.

Time lapse:


Total cabin door rivets: 20
Total cabin door time: 29.4h

Empennage fairing layup and filling

Some of the fairing holes had become too large with countersunking, and we were afraid they wouldn't hold the rivets, so we followed Van's suggestion and made some metal backing strips from 0.016" aluminum (for the record, the strips were 2x 17.25", 2x 24.5", 4x 5.5", 2x 16.5" and 2x 6"):

Backing metal strips for various fairings

We then match-drilled them and used resin to "glue" them on the parts, then applied spray-can primer to give some protection:

Fairings with backing metal strips clecoed on

Fairings with glued and primed backing metal strips


To rebuild the bottom rudder fairing gap without the bulbous light portion, we filled it with expanding foam (Great Stuff Large Gap) - or tried, but made a big mess and then had to trim and sand it down quite a bit. Luckily we had protected everything inside and around the rudder with tape:

Massive blob of expanding foam around bottom rudder fairing trailing edge

Initial cut of bottom rudder fairing foam

Trimmed foam on bottom rudder fairing trailing edge

and then covered that with a couple layers of fiber, sanded, realized we sanded too much, then added another layer:

Laying up fiberglass on rudder bottom fairing trailing edge

Fiber layup on bottom rudder fairing trailing edge

Bottom rudder fairing after first round of sanding

Bottom rudder fairing with second fiber layup over trailing edge

The final result was pretty good for a first attempt at layup, and it matches the rudder nicely:

Bottom rudder fairing with modified trailing edge, after sanding

Bottom rudder fairing sitting in place

To fill the "gap" (different protrusion) of the elevator forward faces between the fairing and the metal, we added a few layers of fiber, then sanded it smooth:

Sanded elevator fairing forward face

Elevator fairing forward face with laid-up fiber layers (and peel ply)

Elevator fairing forward face after sanding

We also used resin with flox and some cab-o-sil to fill the gaps between the empennage fairing and the stabilizers (and later the tailcone), then sanded a smooth ramp around the edges which gave a good fit/look:

Applying filler to the empennage fairing

Empennage fairing after filler cured

HS leading edge on empennage fairing, after filler cured

Empennage fairing with filled/smoothed stabilizer edges (forward edge not yet done)

With the gaps done, I could finally machine-countersink the fairing (using a #40 bit), then enlarge the holes to #27. The last two pages of the plans are kind of confusing and some guess work was involved (like that I had to countersink the two holes that overlap with the empennage gap cover).

Empennage fairing with finished edges and countersunk holes

Finally, we started trying to fill the gaps between the metal and fairings, but there's still a lot of sanding and filling to be done:

Gap between elevator and elevator fairing filled with resin (not yet sanded)

Next in this section, we'll work on the horizontal stabilizer fairings, before we start disassembling the rudder and vertical stabilizer to work on the rudder top and the rudder stop SB.

Time lapse: 


Total empennage fairings time: 40.9h