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

Empennage parts attached

We attached the empennage parts together (at least temporarily), starting with the stabilizers:

Horizontal and veritical stabilizers mounted in place

Fuselage, tailcone and stabilizers all together!

Full-airplane view with the stabilizers on

We attached the elevators, measured and adjusted their travel:

Elevators attached to the horizontal stabilizer

Lower travel limit at ~24˚

Upper travel limit at ~28˚

To get it to the target range (25° down, 30° up), I had to file down the elevator stops a bit:

Slots filed down to increase upper elevator range

Slot filed down to increase lower elevator range

Bottom view of elevator range slot

Final lower elevator travel at ~25˚

Final upper elevator travel at ~30˚

This, unfortunately, created the need to comply with SB18-03-30. It was only then that I realized - and Van's support confirmed, that I didn't need to do any of this :/ instead, the section on flight testing specifies a range of angles, and my original values were within that range, so I'll likely just replace that angle with one that's untrimmed.

With all the parts attached and adjusted, it looked pretty impressive, and gave a real sense of progress:

All empennage parts attached to the fuselage

I'll take advantage of having all these parts on to work on the empennage fairings, before I pull them out again, address the SB, and store them away until final assembly time.

Time lapse:

Total empennage attach rivets: 40
Total empennage attach time: 26h

Rudder cables, pedals and brake system mostly installed

Another delayed post - last year we ran the rudder cables through the fuselage and tailcone:

Rudder cables entering the tailcone

Rudder cables attached with clamps near the tailcone exits

Rudder cables running from forward tunnel all the way to the tailcone

Rudder cables running from the pedals back through the tunnel

Rudder cable tips (temporarily) attached to the rudder

After an attempt at making my own brake hoses and getting OK but not great results, I decided to order them from Aircraft Specialty, and the difference is very clear:

Aircraft Specialty brake hoses

Aircraft Specialty hose (top) vs my previous attempt (bottom)

We test-installed those and the lengths matched perfectly for installing with the Beringer system:

Trial fitting of AS hoses between firewall and parking brake

After quite a while (to wait for a larger batch), I primed the ALIR bracket, as well as the parking brake cable attachment bracket from AS:

Primed ALIR and pedal bracket (along with other parts)

and then put it all together for good, including the rudder pedal itself:

All parts for attaching the parking brake and ALIR

Brackets, ALIR, parking brake and rudder pedal installed in place

Top view of pedal and brake parts

With this, the only remaining part of this section is attaching the hoses permanently and installing the brake fluid reservoir, which I'll do after the firewall insulation and some panel work are done.

Time lapse:

Total rudder pedal and brake system time: 12.4h

Step installation done

On another delayed post, back in Dec 2019 we primed and finished installing the steps, including the inner block:

Step final-installed

Time lapse:

Total step time: 7.9h

Mid-fuselage bulkheads complete (delayed)

There are quite a few steps we did some time ago but never posted, because the videos were too short and I was hoping to have more accumulate, so I'll be posting them soon.

On this one, back in Dec 2018, we riveted the remaining stiffener angles to the center section spars, which was the last step for this section:

Center spar stiffener angle

Time lapse:

Total mid-fuselage bulkhead rivets: 622
Total mid-fuselage bulkhead time: 59.4h