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IMG_19596 hours.

About 10 hours into Phase 1 testing, and so, time for the first oil change, among other things. Have I mentioned I love flying this airplane?   I’ve been flying all week and not blogging much, because I’ve been learning the airplane, how it flies, how it feels.  I can report with great accuracy that gyroscopic precession is a bitch:   If you try to lift the tail too fast, the aircraft will quickly be pointing at whatever is to the left of you.

I’m updating and rearranging the order of things in my checklists, based on where the task is spatially in the cockpit.   This is just good UX design, but like anything else, you work out the best workflows through usage.   For instance:  Put the flaps up before takeoff.   Yes, I know, this should be a post-landing task, and it usually is, but it doesn’t hurt to have it on the runup checklist before RPM to 1700.

The autopilot is more or less dialed in, but it still jitters a little bit.  This is unsettling and needs fixing, but that can happen later.  At least now it doesn’t pull a divergent oscillation in bank.   My fuel flow fix works as well.  I’m now reporting a burn rate consistent with what I expect for a given RPM or MAP.

Day before yesterday, I took a flight to Santa Paula to get fuel and spent a little time buzzing around the Ojai valley.  That’s where the above pic is from.   But following that flight, I decided to take a run at tweaking the idle, which is still al little rough down in the 750’s.  Last time I messed with it, I set it richer to cure the somewhat terrifying issue of it stumbling when advancing from idle to high RPM.   I think I went too far in that direction because since then, it’s run rough at idle and has been a bastard to start when hot.    The hot start is a known issue with FI engines, but even with the proper procedure, it’s difficult, so an adjustment had to be made.   This took the better part of an hour and a half, and the engine has to be hot when the adjustments are made.   This is why I have a nice burn on my hand from trying to get a wrench into the space where the idle adjustment arm is.   I’m still not ballsy enough to adjust this thing with the engine running.  That’s just not going to happen, especially when the exhaust pipes are still hot.   It’s amazing how fast ss exhaust pipes cool, but you don’t want to have a forearm laying on one when they’ve got hot gas blowing through them.

I was going to go fly again, but the wind put the kibosh on that idea:  14kts gusting to 20kts, although right down the runway.  I was too chicken to try to fly that, although I could have probably done wheel landings and i’d have been OK.  Better safe than filling out FAA forms over the wreckage of a balled-up airplane and a bunch of broken runway signage.

But yesterday saw the return of 313TD from aircraft to project.   David and I did the cutting and measuring of the wheel pants and gear fairings.  This is way more difficult than it has to be: You have to take the weight off the gear so you can align the wheel pants and gear fairings in trail.   Fortunately, the local airport mafia purchased a surplus forklift for a couple hundred bucks, and doubly fortunate, Dave knows how to drive one!


I didn’t snap a lot of pics during the actual process because we got busy and stayed busy.   We first jacked up the plane on each side to install the wheel pant brackets, and took the opportunity to bevel the brake pads in an attempt to stop them from groaning during taxi.    Then we used the forklift to lift the airplane by the motor mount just high enough to get the weight off the wheels and the bend out of the gear legs.   Then there was a lot of crawling, measuring, and marking to find the centerline of the wheel parallel to the centerline of the aircraft.   We drilled the aft section to the gear brackets once we had everything lined up.


It’s amazing how hard it is to find a 1″ block of wood in an airplane hangar, but 3/4″ PVC, no problem.  Short sections of that were used as spacers on the vertical to give the 1″ clearance required for the wheel pant.

Then we did the loop-of-string method to insure the gear leg fairings were in trail.   No drilling done there, but marking the position on the gear legs got us what we needed.

This whole process required making as much space in the hangar as possible, so we had to shove the Luscombe outside and move a bunch of stuff around to accommodate the forklift’s dance moves.


The yellow chocks are where the forklift wound up to put the tine with a hole in it directly above the engine mount.

Of course, all this means that the aircraft is down until the fairings can be installed.    This is necessary anyway because I need to do an oil and filter change and a thorough under-cowl inspection.   Fortunately I can do some of the fairing work at home, like paint.   But what’s left is the onerous, fiddly part: glassing in the intersection fairings, then trimming and priming the pieces.   When that’s done, I should be able to bolt it back together and go flying some more.

Brake lines done.

2 hours.

I finished the brake lines. I have pictures, but I can’t upload them because my VPS server keeps denying me ssh and ftp access. Something is whacked. Maybe they’re updating them or something. Anyway, more electrical plotting, planning, and pondering. At some point I’ll upload my wiring schematic and let you all tear me a new one in the comments.

Update: Here are some pics:

Left side gear. The plans actually do say to use electrical tape. Under the tape is some 1/4″ plastic tubing, cut down one side and snapped around the aluminum brake line.

During landing, the gear legs flex quite a bit, in 3 axes. Not only that, the brake caliper moves in and out relative to the wheel. The spiral tube wrapping allows for this movement.

Right side done the same way.

Brake lines attach to the fittings through the firewall to the master cylinders.


2 hours.

Since Dave grew up racing go karts back in SA, it was only common sense that I ask him for some help putting the wheels and tires together. Airplane wheels are a lot like the old-style kart wheels. We made a decent mess with the tire talc, but we got the tubes in and the wheel/brake rotor assemblies back together and torqued. I put some air in them, and left them outside all night, and will check them for leakage later, but I suspect they’ll be fine.

After Dave took off, I started in on the landing gear, just to figure out the brake caliper assembly. The plans are pretty sparse about the actual caliper, which comes as part of the kit from Parker containing wheels and brake calipers. So I’m still puzzling out how to bolt the calipers to the gear legs. I think I got it, but there’s really no drawing showing how to integrate the caliper, gear leg, and fairing bracket. I need to dig into the plans some more, this is kind of important.