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Thought you guys might be interested to hear what sorts of things have required
maintenance/repair attention after the first 20 hours of flight on my 360.
In summary, the plane flies very well. My confidence in it slowly building as
problems are debugged and improvements made.
1. Prop overspeed problem never came back after I replaced the governor. The
root cause of that episode (previously reported) was never established with
certainty.
2. The gear would not retract 3 times now since first flight. Root cause is
not yet found. Cycling the master switch seems to solve the problem. Gear
Minder system is installed. Up relay has been replaced but problem recurred
since. A headache, but not life threatening. The Lancair people think the
black relay may still be the problem and suggest the continuous duty version.
Could also be faulty wiring.
3. Hot idle problem has gone away with the cold weather. Lycoming guy says "If
you think that idle quality is bad, you should see a turbo Seneca. You think
it's going to quit". At least I feel better. Consensus is that heat shielding
and insulation on the fuel pump and other exposed fuel lines is the answer. I
think I still need to have the injector unit checked though.
4. Canopy flange on the inboard side of the weatherstrip on pilots side was not
tall enough to keep the canopy from jumping the longeron under flight loads.
Flange lengthened. Weatherstrip added to canopy to seal - V-seal on leading
edge, standard self adhesive foam on longerons and rollover face. Rollover face
gap is too large for seal I have so I'll have to re-do. A lot of noise comes
from this rollover area. Now the leading edge of the canopy does not fit well
with the header tank - it's proud. DAMN! I had previously cut down the header
tank to make flush.
5. Wing joint at stub is not flush between the two pieces when I install the
wings at final assembly (how can this be? I've shaped this joint at least
twice). The problem turned out to be that the stub wing skin deforms when the
plane is sitting on jack stands. If you shape the joint while the plane's on
jack stands - YOU'LL BE SORRY. to borrow a manual phrase. Do this when the
plane is on it's wheels.
6. Related to number 5, the stub wing skins deflect downward in flight about
half a skin thickness. This prompted the question from Mike Dehate " Uh, Ed,
did you remember to torque the wing bolts?" as we were tooling along at 180
knots. On the ground, the skins have enough flexibility to verify the in-flight
movement. Not sure what to do about it, if anything at this point.
7. Related to number 6, I used locktite (red stuff) instead of safety wire on
the wing bolts and a couple of others. I don't recommend this. I had to remove
the wings later (see below) and getting those bolts out was really tough,
especially since I don't have good access to the inboard bolts due to the
d-section close out panel. For me, the safety wire is better. Attach the
safety wire to your bonded in anchors before you install the wings so that it's
half done before the cursing starts.
8. I had to remove the wings after about 15 hours to go after some lingering
fuel leaks - one per side don't you know. One leak was the sender thread.
Similarly the fuel sump drain threads leaked no matter how many times I
re-applied teflon thread sealant commonly available. The sure fire fix seems to
be this goo my local AP gave me. It's like caramel in consistency and color and
stays like that regardless of time and temperature. Haven't seen a leak recur
since. The other leak was at the rear spar attach area. By the way, for those
of you sweating those last micron size holes that make the baloon deflate after
a zillion hours, at least you can rest assured that actual leaks will make
themselves obvious in a short time. When the fuel evaporates, it leaves behind
its green colorant as a stain and you won't miss it. To go after the rear spar
leaks, I figured they were coming from the attach bolt holes. I dremeled out
the rear portion of BL50 where the plastic nut cover was bonded into the fuel
tank (just for this eventuality). To my surprise I saw absolutely no evidence
of fuel having gotten past the plastic cover and to the nuts. After sanding the
rear of the spar area to clean it up, I noticed green stain growing before my
eyes like some sort of petri dish experiment (and about as welcome too). Fuel
was wicking out the bid between the trailing edge skin and the rear spar.
Obviously a leak existed somewhere but I elected to sand the bid back a bit and
to smear epoxy to try to seal the area against fuel. Time will tell.
9. The rudder is tough to remove if you have installed a tail light per Lancair
option. The trouble is with the connectors you need to have inline. I set it
up so that first I remove the light, pull the wires out far enough so that I can
disconnect the light (the strobe, recognition light combo is worse because there
is more wiring) then remove the rudder and pull the remaining wires through the
leading edge of the rudder. The problem is that when I attached the fairings
for the taillight, I failed to remove enough of the rudder surface under the
fairings resulting in a very small openning to fish the wires and connectors
through. I ultimately had to cut into the fairing to open up this area to allow
more space for the wires to pack in when the light is reinstalled.
10. Here's a good one. For the first time yesterday, the gear would not extend
on command in flight. Now what. I had written down the gear extend procedure on
my checklist so at least I could just read this. And it had been too long since
I had done an emergency gear extension test. It went down at 100 knots without
problem. But I noticed before I pulled the breaker that my hydraulic gages (I
have one for the up circuit and one for the down) were showing 600 psi of
pressure in the down circuit (should have been zero). I already knew I have an
internal leak. What this caused to happen is that the down pressure switch
thought the gear was already down and did not allow the pump to come on.
Dumping the gear manually relieved the pressure (but many times not all the way)
so when I cycled the gear back up, the down pressure did get down to zero. The
presence of gages on the panel, made this a minor nuisance instead of a scary
situation. The gages have also shown me clearly the status of my leak
situation. I'm told that the pump manufacturer has a fix that will make sure
the unpressurized circuit vents to atmosphere preventing this problem.
11. At 15 hours I inspected the inline fuel filter installed just downstream of
the header tank. In hind sight, I would locate this elsewhere because I can't
get at it without removing the header tank. Good news is that there was not a
spec of foreign material in the filter (blue unit from Lancair).
12. I followed Lancair plans when it come to installing the engine mount to the
firewall (I did not use spacers under the stainless steel). The fibrefrax has
compressed over time (as Mike told me it would) and bolt torque is lost.
Unfortunately, retorquing them also means removing the header tank (co-pilot
side access is blocked by the HSI gyro mounted up there). Since retorquing will
have to be relatively frequent until the fiberfrax compresses completely, I got
smart and fashioned some nut keepers made of .090" T6 (use .125" T6 for better
results) with a 6 to 10 inch lever arm simply anchored with a sheet metal screw
to the firewall. The nut is trapped so that I torque the bolt head (not best
practice, but close enough) from the engine side. These keepers should work in
any situation where access is inconvenient.
13. Retorqued the prop bolts (MTV-12B) per requirement at 20 hours. They had
not moved at all.
14. Both roll and pitch servos (STEC 50) were initially wired backwards causing
divergence. Roll was caught on the ground (stick went the wrong way in response
to the heading bug). Pitch was caught in the air (!) This too can be caught on
the ground but you have to read the installation manual very carefully and watch
for the proper trim light to illuminate. If it's wired backwards, the wrong
light will illuminate. The AP doesn't capture altitude hold very smoothly and
while tracking a heading is very good, tracking a nav signal is terrible (it
overshoots and doesn't seem to ever damp out. Wasn't that Zeta or something in
dynamics class?) I assume there's an adjustment for this somehow.
15. The AP also throws a nasty noise on the radios, initially at unicom
frequency and later only on frequencies higher in the band. Affects both
radios. Happens when the AP master switch is turned to on. I haven't yet
started disconnecting servos to isolate the source.
16. I replaced the landing light bulbs to the narrowest beam available from
Variety Lighting in Ventura Ca. I thought the 27 degree beam would be nice for
recognition and general illumination but they just don't through enough light
down the runway. The 13 degree bulbs (65watts each) seem to be OK. One bulb
they sent was dimmer than the other and was defective. What the - - - -.
17. I scratched the canopy (doh!) I used a kerosene doused paper towel prior
to removing all the grit from a recent sanding job. Stupid. The kerosene
trapped the grit in the towel and ground it into the surface. Fortunately the
damage is contained. I switched to a water sponge bath instead to remove all
the grit (winter and no hose available) and followed with soap and water to
remove bugs. The key is lots of water to rinse the grit away. Washing the
inside of the canopy is not easy when it's installed so make sure it is clean
before you install it. I assume I can repair scratches with some sort of
compound and elbow grease.
18. Number 3 cylinder (IO-360 B1F) runs consistently hotter than the rest by 30
degrees or so and crowds 450 degrees during climb, 400 or a touch more during
cruise (leaned for best power). I've tried cutting away more exit area on the
right cowl side, no good. I plugged the heater duct which draws from that
side's rear baffle, no effect. I pulled the heater SCAT tube out completely
because it might be obstructing air flow under the cyliner fins, no good (and a
lot of work too!) I swapped probes (who knows), nope. Oil temps run 165 to 170
degrees normally. The Lycoming guy thinks the 400 is OK but is a little nervous
about the 450. The baffling seems OK but I'm not super confident about it.
19. I have an automatic fuel transfer system installed (3 position switches for
on/off/auto) and am very glad I did this. The VMS fuel monitoring system is set
to give a low center tank warning at 4 gallons remaining in the header tank in
case of auto transfer failure. This worked the other day when I forgot to set
the switches to auto after takeoff and the alarm sounded at the set point. In
addition I put a fuel flow gage on the panel that reads flow into the center
tank (the 2 lines tee together through check valves and then go through the
transducer). Flow with one pump on is 10 gallons per hour, 15 gallons per hour
with both pumps on. With one glance I am certain that fuel is transfering. I
am very pleased with this setup.
20. The fuel tank vents will overflow if the tanks are filled right to the top.
While a nuisance in the wings, it's disconcerting in the header tank. The
center tank vent runs to the filler cap per plans. Under takeoff acceleration,
the fuel shifts to the rear and enters the vent line. In fact, it may develop a
couple of inches of head. It flows out per plans and with the open gear doors,
vapors enter the cabin. I suggest running the vent to the front of the tank to
prevent this. I have a high fuel warning light (in case the pumps don't turn
off when the tank is full) so I've learned to associate this light with likely
fuel smells.
This was long but hopefully it will save some of you some grief with your birds.
It's still fun and each correction makes it a better machine. I was warned that
the first year is spent fixing. Looks like it's true. If there's a common
thread here I suppose it's 'never stop thinking' about what we're doing.
Regards,
Ed de Chazal
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LML website: http://www.olsusa.com/Users/Mkaye/maillist.html
LML Builders' Bookstore: http://www.buildersbooks.com/lancair
Please send your photos and drawings to marvkaye@olsusa.com.
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