« Posts under Phase One Testing

Rockin the clock.

5 hours.

Last time I went flying, there was a very odd glitch.  On the first takeoff of the day, if I do a quick pattern, on base leg before final, I’ll lose my AHRS and compass.   This was intermittent, and I couldn’t reproduce it on the ground.   This week it got worse: If I landed and taxied back to the hangar and shut down the engine, the instruments would come back.  With the engine running, the AHRS and compass are inop.  This is WEIRD.   Strange things happen when voltage dips below 10v, but my backup battery and system voltage both were above 12v.   A quick check of the RCA cables revealed one loose.

Bingo.  RCA cables as aircraft duty connectors are a the worst idea in a collection of bad ideas, but there’s not a lot I can do about it.    Added item to maintenance checklist.   No weirdness from the radio either.

But the futzing around cost me an hour of valuable good weather.  I had planned to get 4 hours of flight time today; I got 2.   That’s only 14 hours left on the Phase 1 countdown clock.   But I need all this crap to stop happening so I can do some real tests.

Onward.

10 Hour Oil Change

8 hours.

OK, it’s the 13.2 hour oil change, but who’s counting?   I got out there as early as I could and set the engine to draining.  The cheesy quick-drain valve on the sump has an absolutely abysmal flow rate, but it has a fitting for a length of hose so you can drain it into a container and not get dirty oil all over the place.   I set it going and worked on other things.   After it had put some oil in the bucket, I took the oil filter off.   This is tricky, because the spin-on oil filter is basically a can full of dirty oil that just wants to dribble it everywhere it can.   The neat trick I figured out is to wrap a rag around the bottom of it while taking it off.

The next thing to do was cut the filter apart and have a look at the filter element.  The guys left an oil filter cutter on the workbench for me, but it was the wrong type, and didn’t work with my filter.   My filter has the threaded fitting on it, and this cutter is designed for a filter with the threaded hole.    No big thing.   I just put it in the vise and cut it apart with a rotary grinder.

I found no metal bits on the filter element.   None.   That was very cool.   That means my engine isn’t shredding some vital part of itself as it runs.  I also took out the screen and had a look at that. One solitary aluminum chip (which I suspect actually came from the bench I set it down on), and a couple of dark, non-metallic flakes and that was it.    I spun on the new filter and safety-wired it up, then replaced the oil screen and wired it.

A fairly detailed inspection showed no chafing or burning, but there was a weird discoloration on the firesleeve of one of my fuel lines.   I need to check that out, but I think it’s just from some oil that got on there before.

And finally, today, I dialed in the governor.  I had been getting a max takeoff RPM of about 2459, which was enough to get it in the sky, but the takeoff power on that engine is supposed to be 2700.   A turn and a half of the fine pitch screw on the gov, and my takeoff RPM is now 2650.   I’ll call that a win.    The weather turned out to be decent – clear skies with wind 11 at 260, so I got a chance to fly a bit.   Maintenance clock was reset to 25 hours, and I’m back to testing.

No More Wobble.

16 hours.

Going to have to sum up last week as well.   Last weekend I did the fiberglass layups on the intersection fairings.   I hate those things.  As is typical with Van’s fiberglass, the fit is garbage.   Add my lack of skill to that, and the result is a set of ugly  fairings that just barely managed to get the job done.   I may wind up reworking the whole landing gear fairing mess, but for now, these will do.   I think if I actually make them smooth and trim off the excess, I’ll get a couple of knots out of them, but the process went like this:  Saturday – Fiddle with wet fiberglasss layups all day.   Sunday – trim the extra bits off, install some platenuts for mounting hardware, go flying.

That’s when I noticed the wing wobble.  running flat-out, with ground speed at around 190mph, trimmed up, the slightest bounce on the stick would cause a divergent oscillation..  This is without the autopilot, au naturel.   Bump the stick, the wiggle starts and just gets worse.    So I had to leave it for another week.

This week:

2 hours fiddling, almost 3 hours flying.  I can live with that.   First thing on the agenda was to double check the gear leg fairing alignment.   No issue there.   Next was clocking the governor back a couple of notches on the control shaft to get more RPM on my takeoff run.  It currently tops out at 2549, when it should be around 2600-2650.   One notch is too coarse of an adjustment; I wasn’t able to cycle the prop during runup, so I had to set it back to where it was.    With that fixed,  I went up just to confirm the oscillation, and sure enough, predictable and repeatable.   So I came back down and checked my rigging.  Turns out, one of the ailerons was off.   Not sure how that happened, but whatever it was, it wasn’t enough to cause a problem with the gear fairings and wheel pants off, at least not until the autopilot was engaged.   The AP couldn’t keep up with the oscillation either.    And, because I’d read about it, I checked the trailing edge of the ailerons.  The control surface is supposed to be absolutely flat from front to back, and then it wraps around where the trailing edge is bent.   This being a quickbuild kit, you’d think they’d be just fine.   Not so.  If the surfaces bulge outward at all, they can cause instability, so you do the heavy-wing treatment: Squeeze the trailing edges so the top and bottom are flat and not curved outward.   Even a little convex is OK.   But the idea is to go easy, not even enough to notice visually.

That was the magic bullet.    Hands-off, the stick stayed rock solid.   Repeating the bump test had the wings settle back to trimmed bank angle.   The autopilot was still a little twitchy though.   The fix for that was to move the AP control linkage to the innermost hole on the servo arm.  Less motion, more precise control increments in the stepper motor.   So that was awesome.   Being able to steer the plane with the heading bug is cool.

With everything trimmed up, balls to the wall, I managed to get 192mph ground speed in level flight.   The fuel burn was absolutely decadent, but it was pretty cool to go almost 200mph.   Oh, and the oil door stayed closed, which was nice.

So I did some more speed runs and spent some time getting familiar with the new handling.   A little different with gear fairings.   It doesn’t slow down as fast, for one thing.   I landed at SZP, went back to OXR, then spent some time in the pattern.   Landings are a little different as well.

Wow, this thing is fun!

8 hours.
1.8 flight hours.

I got off to a late start, and didn’t get to the airport until about 10:30. I got the cowling back on and programmed in the autopilot numbers Matt sent me from MGL. I got off the ground and saw my #4 cylinder was reading totally cold, which was not right, because the plane was making full power just like it’s supposed to. I turned around to land, and managed to sneak in ahead of Derek Spears, who brought the family up for lunch.

After that, I burned some more gas, climbing, turning, generally getting the feel for the airplane, and doing it with the throttle rammed to the boards for cylinder break in. The numbers for the autopilot worked pretty well, and I could steer the plane by changing the heading bug on the EFIS. I have no words for how cool that is. It was still a little springy though. The correction the AP did had a little bit of oscillation left in it, so I’ll fine tune it and see what I can get from it. Most people have trouble with the pitch servo, but mine dialed in just fine. I got a couple of landings in on that flight.

I put about 1.8 hours on the plane today, and it would have been over 2, but on my last flight of the day, the oil fill door popped open in flight. Surprising, but not problematic. I headed for the deck and got into the pattern, then set down and burbled back to the barn.

One thing I’ve been noticing is that my fuel flow is ridiculously high, according to the little gizmo on the EFIS. According to that thing, I’m burning 45gph on takeoff and 30 in cruise. Last time I looked, this wasn’t a 414 or a twin Bonanza, so like, WTF?

Fuel flow works by doing some clever math using the k-factor of the flow sensor. When I got my sensor, there was a tag that said 16-3496. I assumed 3496 was the k-factor and dutifully entered it into the EFIS when I set it up. But MGL EFISes are metric, internally. That means the k-factor on the American FloScan sensor has to be converted. 3496 x 10 / 3.785 = 9236.46, which will probably give me the fuel flow numbers I expect.

First Flight!

4 hours.

Yesterday, 313TD got some air under the tires.   Weather was perfect: Wind 260 at 4, clear sky, visibility unlimited.   This was actually a couple of firsts for me.  It was my first taildragger solo, my first flight in my airplane, and my airplane’s first flight, period.

Shelley, Dave and I arrived at the airport at about 9:45AM, and we spent  a bit of time waiting for the wind to flip over from 090 to 260, the direction of the runway I’m authorized to use in Phase 1.   We busied ourselves prepping the airplane.   We cleaned off the plexiglass, removed the stray items from the cockpit, and generally got things ready to go.   Ron was there briefly to go up to the Chicken Strip with Owen for lunch, and he loaned me his handheld radio, which Dave and Shelley used to monitor the tower.

I went through my engine start checklist, but somehow missed turning off the 430W prior to start, which was bad, because the power drain forced it to go offline, and when it came back up, it had to verify its database.    That takes a while, and I was freaking out a little bit, thinking I’d just burned my radio and would have to abort the flight.

Eventually, it did come up and I was ready to go.   I did a radio check with ground control, then taxied out to the runup area at runway 25.   I did my runup checks, then called the tower.   “Experimental 313TD at RWY 25, first flight in phase one testing, intend to turn right, then climb to 4000′ and remain above the airport.”

They cleared me for takeoff right behind Owen’s Bearhawk, which was kind of cool.   I couldn’t really tell if I had a heavy wing or not.  I didn’t have to fight it to keep it wings level on takeoff, if that means anything. The rolling around you see in the video is me not holding the stick all that steady.  I couldn’t tell you what my angle of climb was, but lowered the nose a bit to see if I could get my CHT’s down a bit.

By the way, without a couple hundred pounds of flight instructor in the right seat and only half fuel, this thing jumps into the air like it was beamed up from the Enterprise!

On climbout, #2 and #4 hit the caution mark at 400, but the nose-down brought them back into line.   I climbed to 4000′ doing slow circles upward.   Once I had 1500′ made, I pulled the throttle back to 2500rpm and MAP to 25.  I fumbled it a little bit, but I still don’t know the controls that well.   I also fumbled setting my transponder to altitude.   Never mind that there’s a giant button on it to engage altitude reporting.  OXR didn’t see it, and Pt. Mugu approach didn’t see it, but  I eventually figured out I needed to push the damn button marked “ALT” instead of “ON.”  But hey, the transponder works, so that’s nice.

Once I was at 4000′ and my instrument shenanigans were done, I could concentrate on feeling out the airplane.   Among the first things I discovered was that my airspeed tape was inoperative.   I guess of all the things that could be inoperative up there, that’s the easiest one to deal with.   I blipped the trim control a little bit and that seemed to level out the wings, but since I have no trim position indicators, I’m not sure it was ever centered to begin with.   Like I said, I didn’t feel like I had a heavy wing, and it didn’t take much trim to correct it out.   Once I stabilized, I trimmed up altitude and it flew hands off, which was awesome.   I guess I built a more or less straight airplane.  More accurately, the Filipino factory workers who did the QB kit built a more or less straight airplane, but I think my sweep/twist/incidence measurements and final drilling were pretty much on.

Without airspeed, I really had no idea when I could deploy flaps, so I did my best guess at slowing down to Vfe for slow flight.   I remembered the sounds (engine, wind) from training with Mike Seager, so I figured if I matched that, I’d be OK.   I got to slow flight with flaps extended and felt it out a little bit with shallow turns.  I wasn’t ready to stall it just yet, but I figured out about where it will stall.   It also feels different from Mike’s plane in that it’s a bit draggier with the gear fairings off.    I did this for a bit, making turns, going back up to cruise, all the while making sure I didn’t fly over populated areas per my op lims.

Naturally, I forgot to set a flight timer, but after the slow flight practice I decided to come home.   I called Mugu, who had been providing me with flight following (nice of them) and told them I was heading for OXR airspace.   Frequency change approved, I got OXR ATIS ,then called the tower.   Once again, I said hey, phase one first flight here.   They cleared me to land before I even entered the pattern proper.   I got slow enough to be able to think (probably 110mph or so), and got my downwind checks done.   I followed the sequence and checklists perfectly.   Abeam the instrument landing marks, slow down to 80 (ish) and drop half flaps.   Boost on, prop high, mix rich.   On base, drop the rest of the flaps and get the approach dialed in.   I came in a little fast, probably, and I definitely held on to power a little longer than I should have, but I made a good, straight, soft landing.   I ate up 2000′ of runway, but that’s my prerogative.   Then I taxied back, and we decowled and inspected.

Squawks:

Some oil seeping from the right mag gasket.

Airspeed inop

The airspeed we were able to fix easily: the AOA and pitot lines were reversed, which is why I got an intermittent airspeed reading which coincided with my taxi speed.   The oil, we wiped off and decided to see if it was indeed leaking from the mag gasket or somewhere else.   The amount was negligible.

I was going to go for a second flight, but during runup, the right mag was inop.  Boo.  Abort.   That’s what I fix today.   Here’s the video

 

Airworthy!

15 hours.

That includes Friday and Saturday.

You folks who follow this blog on Facebook already know this stuff, this is more for those who don’t, and the general public at large.

Last time, I had just made my appointment for inspection on 1/25.   I spent a bit of time freaking out about this because work is a torrential downpour right now and there was enough stuff to do to make me concerned that we wouldn’t finish by Saturday.   I had planned to take Friday off, but there was a thing at USC I was scheduled to do so that was out.   But like a bolt of lightning from on high, the USC event was cancelled, so I took a vacation day.

David Prescott , who’s appeared on these pages before, volunteered to help, so we were on the freeway at 8am on Friday morning, heading to Oxnard with the intention of crossing every t and dotting every i we could find on the ship from one end to the other.   We cleaned out all the metal chips, spare hardware, and tools that have collected in hard-to-reach places over the years, securing wires, removing the remaining access panels, and generally making things ready for the inspection.   There was a fair bit of safety wiring, which Dave did, while I fixed and dressed wiring underneath the panel that had come undone during the Great Magneto Adventure.  All the stuff on the list from last time got done, and as many of those chronically deprioritized small fixes as we could do.

Then we cleaned up the shop.   That hangar is a study in constrained chaos.  There are two and a half airplanes, a car on a trailer, and an empire of tools and hardware.   Our goal was to make my rented portion of the hangar as clean and clutter-free as possible.   Difficult with an asphalt floor, but we did really well.   All the tools were put away and organized in such a way that it would be easy to find what we needed if we had to fix something during the inspection.   That was Dave’s doing.   Very smart.  We both knew that the greatest amount of wasted time is in the act of looking for something that should be in a known, proper place.   This time, adherence to that idea paid concrete dividends.

As we worked through the plane, I checked off items on the 100-hour condition inspection checklist, at least the ones that applied, since this is a new aircraft.   We also spent some time measuring the control surfaces’ travel to ensure they were within limits called out by the construction manual.   They were, for the most part.   Flaps need a minor adjustment, ailerons, rudder, and elevators are good, and we got the elevator trim adjusted correctly.

I also wound up adjusting the fail-safe spring on the purge valve.   Ron found me a spring the other day, which worked fine, but I twisted it around in kind of a half-assed manner to get it to work.   Friday, I undid it and reworked it with a pair of safety-wire pliers so now it looks clean and is much better.

I couldn’t tell you all the little things we did.   Mostly it involved getting eyes in places that haven’t been looked at in years and fixing anything that needed to be fixed and generally making temporary solutions permanent.

Saturday was the inspection itself.

Adam Valdez got there at about 8:30, and the family had come along for the ride.   While they were getting some brunch, Adam performed a very thorough inspection of the aircraft.   He started at the tail and worked his way forward.   He said that usually he finds small things, like missing cotter pins, nuts, things like that.   I was thinking, you’re not going to find much.   We went over this thing yesterday.   But sure enough, he found some minor issues that we didn’t even think to check for.

At about 9:30, David Voelker of the FAA stopped by to brief me on what my operating limitations and some of the regs regarding phase one testing are.   Mr. Voelker’s an excellent guy.  He loves general aviation, and he makes time to personally contact each new builder to brief them, which is really cool of him to do.   He doesn’t have to, but he does.

“How many hours do you have?”  He asked me.

“About 125 or so,”  I said.  “I’m not sure, I didn’t bring my logbook.   Today was the last day I expected to go flying.”

Then he informed me that I am now a test pilot.  A TEST PILOT.  Let that sink in for a while.  And as a test pilot, I have certain responsibilities, number one of which is to protect the non-participating public from a fairly dangerous activity that we as aviators and experimental airplane builders willingly and deliberately choose to do, but that they don’t.

I don’t think he was expecting me to have such a low number on my flight clock.   He did ask me about tailwheel training, and transition training, and currency.   Then it was a bit of a socratic dialogue about the regs, and the purpose of all the questions he asked me was not to make sure I could quote the regulations chapter and verse, but that I understood that the purpose of my operating limitations is to keep me within the constraints of the prime directive stated above.   It boils down to:  don’t fly over population, leave yourself an out, and it’s OK to tell ATC “unable to comply” if their directions put you in conflict with the above.   Lots of good advice, and an invitation to call any time I had a question.

Altogether an informative and pleasant process.

While this was going on, Adam had found the most onerous squawk of the day:   None of the rudder pedal attach bolts had cotter pins on them, but there was nothing I could do about it in the middle of my briefing.   Fortunately Dave picked up the slack and got out ahead of Adam, looking for loose jam nuts and other similar gaffes.

The only fly in this otherwise smooth ointment was one of the local airport bums who really wasn’t able to take the hint that this wasn’t a social gathering and it might be best if he came back in a couple of hours after everything was over, and please, for fuck’s sake don’t ask the FAA guy or the DAR inane questions while they’re trying to impart information to me that might save my life or my pilot’s license.   And absolutely do not start kibitzing while i’m upside down under the panel trying to put 8 sets of cotter pins on bolts I can’t see and dropping 3/8″ wrenches and pliers on my face.

I was debating throwing him out of my hangar, but he’s one of the old heads at the airport, and I didn’t want to risk pissing him off.  You never know the ways people can make your life miserable until they do.   In retrospect, it may have been worth it.

Mr. Voelker headed out, then I worked on the rudder pedal cotter pins for a while.   At that point, Adam was inspecting the engine, where he found a couple of missing nuts and a backwards safety wiring.   He taught Dave the cool trick of safety-wiring drilled bolt heads, which I picked up secondhand.    He also found that the throttle had about 1/8″ of travel left to go full, and the mixture didn’t actually go all the way to lean, both easily fixed by adjustments to the cable travel.

After that, it was time to do paperwork.    Dave took over the cotter-pinning of the rudder pedals, and I sat down with Adam to go over the 8130 forms, operating limitations, and other signature-requiring documents.    With the stroke of a pen and a handshake, I had an airplane!

He autographed my as-yet-unpainted right wingtip, then left us to fix the few remaining squawks.