Padded Fuel Line Under Forward Cover

The plans specify that the fuel lines are wrapped in foam where they pass under the forward center cover.  I used some adhesive weatherstripping under a couple of spots between the fuel line and the floor.

I also put some foam on the underside of the cover in the same spots to sandwich the fuel line when the cover is installed.  I also put a small piece where the aft angle is relieved just in case vibration would allow it to contact the fuel line.

Left Wingtip Lens and Cowl Prep

I couldn’t go down to the hangar tonight, so I worked on some of the pieces I brought home.  I finished trimming and sanding the left wingtip lens and drilled it to the wingtip.  I’ll have to install the nutplates at the hangar where the rest of my tools are, but other than that the wingtips are ready for flight.  There is still a bunch of finish work before I’ll be happy with these, but I want to put that off until the landing lights are aimed right, then I can do all of the fiberglass finish work and put a coat of primer on the wingtip.

Speaking of fiberglass finish work, I resumed work on the cowl to get it ready for a coat of primer.  There are still a few spots that have pinholes, so I’ll be doing a little epoxy work before priming.  I spent a little time first with a file smoothing out little high spots and fixing a couple of epoxy runs.

Prepping Plane for DAR Visit

I got started tonight by taking a couple of more weight and balance measurements.  I had forgotten to include the plenum, but I decided to also throw the wheel pants and gear leg fairings on at their approximate position.  All of that helped move the CG forward 0.22″, but increased my empty weight to 1110.  After that, I took a measurement with me in the plane to find out exactly where my CG is.  Unfortunately, I’m 0.24″ aft of where Van’s says the pilot’s CG should be.  This had the effect of moving the plane’s CG back by 0.05″.  The net result is that the CG will be roughly 0.17″ forward of where I calculated on Sunday.  That still puts me 2.48″ aft of the forward CG limit, so I’ll still have to add some weight up front.

Afterward, I pulled everything off or out of the plane to get it ready for inspection.  I’ve still got a fair number of items to knock off the list before that happens though.

Put Together Paperwork for DAR

I spent a little time tonight wrapping up the paperwork for the DAR who will be inspecting my airplane.  From the upper left, we have the registration, 8130-6, notarized 8130-12, program letter, weight & balance, three-view and condition inspection.  I emailed everything to him tonight and am planning on meeting with him this Sunday.

Weight and Balance

My big goal for the day was to compute the weight and balance.  To do that, I needed to have the plane ready for flight.

In preparation for reinstalling the canopy (hopefully for the last time), I applied a strip of UHMW tape under the leading edge.  This will help the flange slide over the weatherstripping without catching and dragging on it.

I then used a razor blade to trim the tape flush width the edges of the skin.

I then installed the wing root fairing.  I didn’t bother tightening all of the screws all of the way since that wouldn’t change the weight or CG.

The plans say to trim the rubber seal to just touch the fuselage, but I think it looks better to leave the whole seal and have it flare out at the fuselage.  It probably seals against the fuselage better too.

I also installed the wingtips with the landing lights and mounting plates.

I reinstalled the spinner and the cowl.

Jenn stopped by the hangar and helped me install the canopy.

I then installed all of the interior.

After installing the empennage fairings and all of the wing inspection panels, I leveled the plane and put it on scales.  I came in right at 1100 lbs which is great.  It probably means I’ll be around 1130 or so with gear fairings and paint.  My center of gravity is farther aft than I would have liked at 81.35″, or 2.65″ aft of the forward limit.  This makes it fairly easy to load aft of the aft CG limit, so I’m likely going to have to shift some weight forward or add more weight under the cowl.

Leak Checked Pitot System, Empennage Nutplates, Unusable Fuel and Firewall Passthroughs

I spent some time this morning working on the left wingtip lens before heading down to the hangar.  Since I reworked the pitot and AOA tubing yesterday, I wanted to leak check it today.  I disconnected the tubing at the new fitting in the wing inspection panel and attached some 1/4″ ID latex tubing.  I could roll up the other end of the tubing to increase the pressure in the pitot system and test for leaks.  AC 43.13 recommends increasing the pressure to an indicated airspeed of 150kts and then clamping the tubing for 1 minute to check for leaks.  As long as the leaks aren’t substantial enough to cause the indicated airspeed to drop more than 10kts, then everything is fine.  After 1 minute, I had a 3 kt drop, so I’m in great shape.

Next, I tackled installing the two Click Bond nutplates in the horizontal stabilizer.  I used some hemostats to scotchbrite and solvent wipe the inside of the horizontal stabilizer around the hole and then fished some 0.025″ safety wire up through the hole and out through the nose of the inboard end of the horizontal stabilizer.  I pushed the safety wire through the end of the silicone installation plug so that I will be able to pull it back through the hole.

The Click Bond adhesive I had had dried up, so I mixed up some epoxy with West System 404 structural adhesive filler.  I applied a little bit on the flange of the nutplate and then pulled it through the hole.

Here’s a picture taken through a mirror at the installed nutplate.  Once the adhesive cures, I can just pull out the silicone plug.

With the new fuel pump installed, I decided to determine the unusable fuel.  I rigged up the hose from the spider so I could capture any fuel pumped to the engine.  I dumped 16 oz into each wing and then ran the fuel pump until nothing came out.  Finally, I drained the fuel in each tank to see how much unusable fuel there was.  I drained almost 7 oz from the left tank and 6 oz from the right tank.  I then dumped the fuel back in the tanks so that it could be included in the weight and balance.

My buddy Greg noticed that the firewall pass-throughs didn’t grip these cables very securely.  I removed the eyeballs and wrapped a couple of layers of aluminum tape around each cable and then reinstalled them.  The cables are rock solid now.

Primed Canopy and Fixed Pitot and AOA Tubing

I sanded down the epoxy I applied the other night and painted on a few coats of primer.  There are a few pinholes I need to deal with, but this is good enough for first flight.

Between coats of primer, I fixed the pitot and angle of attack tubing.  I had previously made these connections in the wing root, but that was a mistake since there’s no room to ever service them.  I had planned on running new lines down the conduit, but I realized I could use the same lines if I added a couple of additional connectors in the wing.  I disconnected the tubing at the pitot tube and slid it inboard inside the wing enough that I could pull the excess through the holes in the fuselage.  These fittings will now be trivial to service if that is ever necessary.

I then cut the lines in the wing and took some longer pieces and ran them from the pitot tube to these fittings.  This is better anyway since I can disconnect the tubing here and pull the pitot tube out of the mount.  This is looking up into the inspection port just inboard of the pitot mast.  With the way the lines were previously run, pulling the pitot tube out of the mount required disconnecting the lines right at the top of the mount.  That wasn’t too painful, but reinstalling the pitot tube was a real pain since it required hooking up the tubing entirely by feel.  This way, the fittings are easy to inspect and verify correct installation.

Worked on Left Wingtip

Now that I have a pretty good idea how the wingtip lights will be mounted, I could do the work on the other wingtip.  I marked and cut out most of the recess.

I then fabricated an approximate duplicate of the right mounting plate and then trimmed it to fit the left wingtip.  The two wingtips are slightly different, so I couldn’t make an exact duplicate.  I then transferred the plate mounting holes and the center set of light mounting holes.  You can see in the previous picture that I also drilled the plate to the wingtip.  All that is left now is to finish getting the lenses to fit properly.

New Fuel Pump, Wingtip Lights and Canopy Fairing

I got my replacement fuel pump from Andair, so I ran down to the hangar tonight to install it.  I pulled the old pump out and removed the fuel filter.  Since I’ve pulled fuel from both tanks, I wanted to clean the filter to remove any debris that might have made its way into the tank or fuel lines during construction.

Despite my best efforts to keep the tanks clean and sealed and clean the fuel lines before installation, there was a surprising amount of junk in the fuel filter.  I rinsed everything in a few ounces of gasoline.  It looked like mostly dust and small sandy particles, but there were a couple of small metal particles mixed in.  It’s good to get all of this out of the fuel filter before the first flight.

I lubricated the o-ring, safety wired the filter and reinstalled it on the pump.

Here’s the completed pump assembly with wires cut to length and a molex connector installed.

Finally, I reinstalled it in the plane and re-torqued all of the fittings.

Next, I installed the wingtip so I could get an idea how the light was aimed.  It looks pretty high, but I’ll need to level the plane to be sure.  I’m pretty happy with how bright this is.  Here’s the hangar across the way with the light on.

And here it is with the light off.

To get a better idea how the light is aimed, I pulled the plane out into the taxiway and put the tail up on my chair to get the fuselage level and then turned the light on.

I adjusted the light until the beam was roughly level.  You can see it does a pretty good job of lighting up the taxiway.

I walked to the far end of the taxiway to get an idea how much light was making it down there.  The picture doesn’t really capture it well, but it was uncomfortable to look directly at the light, even from this far away.

This picture of the shadows cast by my legs gives a pretty good idea how well the far end of the taxiway is lit up.

Finally, I resumed work on the canopy fairing.  I started with sanding the fairing down to be flush with the two layers of electrical tape and got the overall shape where I wanted it.  Next, I removed the upper layer of tape and sanded the fairing down again to be flush with the remaining tape.

After taping over the exposed parts of the canopy bubble, I mixed up some epoxy with black pigment and applied a sealer coat on the fairing.  After this cures, I’ll sand it down and apply a coat of primer.