Joshua's RV-9A Project

Called in late to work and headed off to the airport this morning to take care of the transponder/altimeter correlation check that’s required before using the transponder.  I’d talked to the local shop about this last week, so I stopped in again to be sure they still had time to do it, then taxied the plane over to their hangar.  Out came the guy with the test rig, and after finding the serial numbers for the encoder (a function performed by my EFIS) and transponder, he asked if the EFIS could be installed in a certified airplane.  “No,” I said, “but this is an experimental aircraft.”  He told me it didn’t matter, and that if it couldn’t be installed in a Cessna, he couldn’t certify it.  I advised him that I didn’t believe this to be true, and he wandered off to ask someone else.

When he returned, he said OK, he could do it, “because the encoder is built into the transponder.”  Not so, I knew, because I wired and plumbed the panel myself, and I have the installation manual right here on my Ipad…but I wasn’t going to argue the point, since he was now saying he could do it.  Then, he had me pull the transponder out of the rack, whereupon he pointed to what appears to be an unused small screw hole on the back of the case, and told me that this was the static port, and I needed to have a static line plumbed to it; without that, I would be encoding the cabin static pressure, and they’d sent someone else away for the same reason before.  If I were to put the transponder in a vacuum chamber, he told me, it would read whatever pressure was in the chamber.  (FWIW, the install manual has arrows pointing to that screw hole saying “unused.”)

Well, at that point it was becoming evident that he didn’t know what he was talking about (there is no mention whatsoever in the manual of any static port, plumbing, or built-in encoders), so I took my transponder back, thanked him for his time and the education, and taxied back to the hangar.  Pushed the plane in and went to work…frustrated that I’d driven all the way over and taken time from work for that; now I’ll need to ask for more time to deal with it it later.

I’ll call SteinAir once they open back up after Oshkosh on Wednesday, and see if they have time to make a field trip with their test rig to complete these checks.  At this point, I don’t really have much of a choice but to have someone travel in to do it, at whatever that costs.  I suppose I could fly with the transponder disabled and locate a friendly shop later at one of my Phase I airports, but having the transponder active in the (busy-ish) airspace around the cities is an aid to see-and-avoid, since traffic systems and TCAS can’t do anything with non-transponder aircraft.

Later in the day, talked to the DAR about the airworthiness paperwork, and confirmed that they really do need (or at least want) a full hour of ground run on the engine, despite the 2-hour test stand run, and all systems checking out OK in the runs that have been done so far.  Had the FAA forms notarized, and dropped the packet in the mail to the MIDO on the way home from work.  I’ll call them later in the week to be sure they got it, and then let the DAR know it’s ready.  At this point, I think we can comfortably say that the inspection is “pending.”

Headed off to the airport with Allison tonight, to calibrate the fuel tanks.  We pulled the plane over to the pumps, and she sat in the cabin and pushed buttons while I added fuel, 2 gallons at a time, to each tank.  I also wanted to calibrate the dipstick tube that I made at the same time, but it seems the diameter is too large — the tube won’t hold the fuel.  I’ll have to find a smaller tube and redo that part later.  30 gallons of fuel later (15 in each tank; the gauges stop increasing at around 14.2 gallons), the tanks were calibrated.

Rather than tow the plane back to the hangar with an extra 180 lbs on board, I had Allison move over to the passenger seat, and I fired up the engine and taxied back.  First, we went down to the run-up area and did a run-up, mag check, and static RPM check.  Back to the hangar, I tried an idle RPM check before shutting down, but the engine wanted to quit somewhere south of 500 RPM, so it looks like I’ll have to adjust the idle stop up a little higher.  Allison thought taxiing around the airport was neat, though it was a bit loud for her.

Before putting the plane back inside, I parked it in front of the hangar and took a series of photos that I’ll send in as the official inspection packet photos, along with some “glamour shots”…

Back in the hangar, we removed the cowling, wing inspection panels, and tail fairing.  Later this week, I’ll get the rest of the fairings & panels removed again.  I looked over the FWF for leaks or chafing and found neither.

I put together the rest of the inspection packet tonight, and printed off a shipping label; hopefully I’ll talk to the DAR tomorrow and ship off the packet from the post office at work.

Today was the day to weight the plane, I hauled the scales to the hangar and spent the afternoon getting ready. Essentially, this meant installing every panel, cover, piece of equipment, cowling, and so forth, to get the airplane to the same weight condition it will be for flight. The process took several hours to complete, and I ran out of screws and washers when I was several short of the end. I did get everything installed, though, inside and out. Wing root fairings, cowling, forward carpet.

I also remounted the fire extinguisher on the tunnel cover between the seats, as I mentioned earlier. Menard’s didn’t have any suitable spacers that I could find, so I just used a stack of large-area washers for now; I’ll replace them with something lighter when I find or make it.

Once all the panels and covers were on, I installed the seats and the seatback braces, then adjusted the shoulder harnesses and trimmed the excessive extra length off the strap that runs aft; there’s still plenty left, I could probably trim another 18 inches, but just in case, I’ll wait until after I’ve flown and had a chance to adjust everything.

Drained all the fuel out of the tanks, too.

With everything set, I rigged up the scales, blocks, and ramps, and hauled the plane up onto them. Moment of truth…turns out she’s a bit of a big girl. 1103 lbs. I was surprised, since I have a light prop, non-oversized engine, minimal interior, and only a partial panel. I’ll have to poke around a bit and see how bad it is, but I seem to recall mid- to high-1000′s (1050-1090) being more normal.

Even with the higher weight, the CG seems fine, and all the loading scenarios I can think up are within the envelope. So it comes down to a matter of how much weight there is to add additional equipment before it starts to cut into useful load that’s actually used.

I blame all the primer and interior paint for the weight, and I know some of my fiberglass work isn’t as light as it would be, if someone who knew what they were doing with glass did the work.

So, now I can finish up the airworthiness paper trail and set the government cogs in motion, to bring first flight one step closer.

Spent the day chasing things down and catching up on non-airplane work, as I’ve not done much else the past week.  I did get out to the shop to prep and paint the seatback braces to take to the airport tomorrow.

One of the other tasks today was driving up to Savage to pick up a set of digital aircraft scales.  If I get to the hangar at a reasonable time tomorrow, I’ll be able to get the plane weighed before the day is out, then we’ll only need to deal with the transponder check.  I’m also going to try and get to the fuel level calibrations this weekend, which will put me in a good spot if I need to move the plane over to the maintenance hangar for the transponder check…can taxi it, rather than pull it over.

If that all goes well, the paperwork can go in on Monday or Tuesday, setting us up for inspection anytime next week or beyond (that depending on the inspector’s schedule).

I will probably try and get one day off work next week again, for more transition training — we’ve completed 9 hours, with 6 remaining before I’m insurable.

For other locals looking for scales…the scales are owned by the MN Soaring Association, and rent for $50, including a set of ramps.  I saw the web page and sent an email in the morning, and had them in hand a few hours later.  All the info is available on the Soar MN website.

Airport-hopped for another 3 hours of transition training this morning, including a climb to 9500MSL…even on a rather hazy day, what a view; 184kts (~212 mph) groundspeed was impressive, too.  Flying a panel with a traffic system really highlights the fact that there is a lot of traffic out there that we never see — even when we know it’s there, since it’s on the display, and even when it’s relatively nearby.  And autopilot…made cruise flight and descent planning a whirl.  I’ve managed to put the wheels on the ground a couple dozen times now at a bunch of different airports.  A bunch of stalls (power-off and power-on…that deck angle is impressive) and airwork as well.  6 hours left on the requirement.

Back on the ground, the push to complete wheelpants & leg fairings continued.  I got the wheelpants both mounted up, nutplates installed on the inboard bracket, and just using locknuts for now on the outers (miniature nutplates on order).  Safetied the outer bracket bolt, and found one wheel cotter pin that hadn’t been bent.  Drilled access holes for tire inflation & pressure check, and plugged with stainless hole plugs.

Fabricated metal T’s out of .025, to reinforce the tabs at the top of the gearleg fairings, and installed those before installing the leg fairings.  Also removed the nose leg fairing again to cut slots for a hose clamp, install the metal tab T’s, and reinstall.  The upper clamp should prevent the leg from vibrating around; the plans leave it floating free to rub on things, though it’s pretty solid as it was.  The nose leg is easy to align with string, so I did that and buttoned up the nose gear again.  The mains still need to be aligned, but are otherwise done for now (until intersection fairings show up).

I decided that I’ll move the fire extinguisher between the seats, aft of the roll trim lever, for increased legroom, and to position it away from the probable location of any fire.  I’ll secure the bracket to the tunnel cover between the seats; I need to find some spacers, though, to raise it up, since my extinguisher bumps into the roll trim knob when all the way down flush on the cover.

Located the seatback adjuster brackets and hinges, and installed the hinges to the back of the seats.  I’ll paint the brackets to match the interior colors.

Talked to the shop on the field after lunch, and though they weren’t thrilled about it, they did agree to try and find time to do a transponder check, and weigh the plane — if they have time — on Monday morning.  They want to do it in their hangar, not mine, which means of course, that after I drain the fuel out, I get to pull it over there with the towbar…fun.  If they don’t have time for the weighing, it’ll be double the fun, since I’ll get to pull it over there & back twice.

Once we have a weight, I’ll be able to submit the inspection paperwork and get the ball rolling.  We’re close, and I’m looking forward to having it in the air.

Apologies for the previous two days’ posts…I’ve been working on the plane alongside transition training this week, and my mind is trying to absorb all that, and not recalling the precise details of all the build stuff.  Today, we flew for 3.3 more hours (in two blocks), and hammered out 15 landings across 4 different airports.

Before flying this morning, I had time to countersink, deburr, and rivet the hinge into the nose leg fairing.  After we finished for the day, I tried hard to get the rest of the pants & fairings done — didn’t succeed, but it’s close.  Still waiting on intersection fairings, so I’ll either fly without, or find a different source.  I did — after a trip out to buy hoseclamps — get a bunch done, though:

• Fit, installed, and aligned the nose leg fairing.
• Reinstalled the nose pant cap…this essentially finishes the nose gear work.
• Countersunk, deburred, and riveted the hinges to the main leg fairings.
• Trimmed and retrimmed the man leg fairings for fit and brake like clearance.
• Added an extra brake line securing point to the bottom of the leg, to keep the hose from rubbing the fairing as it exits to make its turn aft to the caliper.
• Laid up two plies of glass inside the tabs at the top of the leg fairing.  This’ll be trimmed again later, and filed/heated to fit around the leg.  Set aside to cure overnight.
• Pulled the R main wheelpant and countersunk the attach screw holes, installed the split line nutplates…this one is ready for installation.
• Looked at installing nutplates on the brackets, and found that two regular one-leg nutplates (as I’d been planning) won’t fit on the outer bracket side-by-side.  I’ll need to order a handful of the mini one-leggers, if I can figure out the part number…also, more #6 tinnerman washers, as I’ve run out.

Back home to do chores, rest & recover…more training at 7:30 am tomorrow.

Milestone: crossed 1900 hours of work on the project tonight.

Bled the R brake system and tested…no leaks yet.

Installed the seat pans with a few screws, and dropped in the pilot seat.

Worked on the nose pant more, countersinking for the attach screws and adding nutplates.  Fit it back to the fork and finalized the size of the towbar holes.  Added an air access hole for servicing the tire, after finding the spot on the pant via laser.  Fully seated the towbar and marked it with yellow tape, as a witness line to full engagement.  This should eliminate guessing as to whether it actually went all the way onto the pins.

Spent the rest of the session working on the leg fairings.  Tracing the plan, cutting to size, finding the no-twist state, taping it secure, marking & drilling the hinges.

Removed the peel ply, reclecoed the pants, and final drilled wheel pant attach holes to #27 for a #6 screw.

Lots of on-off-on-off to get the tire gap on the nosewheel pant right, and to trim the hole in the top so it doesn’t hit the leg when the wheel turns.

Most of the day was spent working on wheelpants, but before that, I temporarily attached the underwing inspection covers with screws — more prep for weighing.  This also necessitated drilling out and replacing one nutplate that had no threads.

Set up the strings and lasers to align the wheelpants, and worked through the right one first.  With the process understood and completed once, the left pant went significantly faster, as it’s basically just the reverse of the right.  I opened up the tire gap to a finger’s width all around.

The front wheelpant was a different trick, and I did eventually get it satisfactorily drilled.  The instructions have you putting on and removing the aft pant by sliding it over the brackets…because the front of the pant is tapered down (unlike the mains, where the split line is at the widest point), you have to stretch it out to fit it over the brackets.  This went fine the first several times, but eventually, I stretched it and a big vertical tear zipped open in the left side.  So, after finishing the fitting of the pant and nose cap, and making sure it was able to pivot with freedom, I pulled all the pants and did some glass work.  Patched the nose pant back together with glass tape and epoxy, and added some buildups on the inside of the main pants, to fill gaps between the pant and the brackets.

I need to bring a larger step drill to finish the towbar holes (3/4″ isn’t big enough for the bar to enter through).  Then, all the nutplate work has to be done on the pants and brackets.  After that, leg fairings…  No word on an ETA of the intersection fairings yet.  I did some internet digging and the data indicates that the pants and leg fairings make up for most of the speed increase (10-15 kts), with the intersection fairings contributing just a couple kts of that.  I’ll weigh with the wrong fairings taped in place, since the replacements should weigh about the same; any difference ought to be negligible.

And, I still need to bleed the right brake.  I would have done it today but it always seems to make a mess; I want to pick up a foil pan to catch the drips under the caliper so I don’t make a big mess of the hangar floor.

Still avoiding the wheelpants, but I knocked nearly everything else off the list, so if I make it to the hangar at a reasonable time tomorrow, I won’t have a choice but to begin…

Cut foam blocks and inserted them into the gap between the upper & lower bars of the wing spar, where the spar joins the fuselage.  This should help prevent air ingress and cabin drafts.

Removed most of the zipties from the ignition wires and replaced with “tubing clips” from McMaster.  There are a couple spots near the ignitions where wires are tied together from various directions; in those places the clips don’t work (they are designed for parallel wires), so the zipties remain.

Opened the right brake system at the pilot’s pedal, in order to fix the weeping leak there.  When I arrived today, a small pool of fluid had formed on the cabin floor, so it’ll be good to get this fixed.  Removed the hoses, and the elbows, and cleaned off all the EZ Turn.  Reinstalled with Loctite 567, which is specified as a high-pressure thread sealer.  The tech sheet for it says that full cure takes up to 24 hours, so I won’t rebleed that system until tomorrow, to give it the best chance of sealing up well.

Added RTV to the inboard lower cylinder baffles, where the tapered-fin “issue” is.  This fix has been reported to work just fine, so I’m going to try it before committing to a complete removal & reinstallation of the baffle system (and everything that’s mounted to it).

Installed threaded hex plugs in the tie-down holes.  The extrusion that the tie-down rings screw into are tapped deeper than the ring bolt is long, so it’s possible to thread them in too far and gouge up the outside of the skin (and any paint that may be on it).  The plugs I found are just the right length to thread in all the way, and provide a positive stop for the rings, clear of any skin damage.

Replaced the screws on wingtip and leading edge light lenses with Torx-drive, after receiving an order of the correct size from microfasteners.com.  These’ll be used for all non-structural fairings, panels, lenses, etc.

Drilled a matched set of holes in the upper corners of each crotch strap bracket.  Deburred, and installed a bolt through both halves, with a stack of washers between to act as a spacer.  This secures the floppy forward piece in place, making it less prone to bending, and easier to align the screws when installing the seat pans.

Resecured the wire bundle for the pilot stick grip.  The stick is much more comfortable now that it’s shorter…my arm rests comfortably on the leg, with fingers around the grip.  Vacuumed all the debris out of the cabin.

Placed the empennage fairing and elevator horn access panels in place, and secured with a few screws; the rest of the screws are just finger-tight in.  I need to install all the panels, fairings, screws, etc, in anticipation of having the plane weighed (once the wheelpants are on).  I’ll also drain out all the fuel.  After weighing, fuel will be added in increments to calibrate the tanks & dipsticks.

I’ve taken the next week off work, to spend time getting transition training.  When not doing that, I’ll be working on the plane; I’d like to get the pants on, W&B done, transponder check done, and inspection paperwork submitted…we’ll see how realistic that goal is.