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Hi Rick,
As you read this keep in mind that I did not build my own airplane, but
have a few thoughts for you. Mileage may vary. I have owned both a
235 and now a 320.
Fuel leak: I had a small fuel leak in my 320, where one of the
root attach strap bolts penetrated the spar. Tiny leak let an awful
lot of gas out. A little sealant on the threads solved it. Point
being that you may have a VERY small leak. If you are concerned about
the skin integrity you could perform static load tests on the assembled
wing. But, IMHO using liquid sealant (the "slosh" method" may very
well solve your problem).
I have heard tell that some people did not even need the sealant. I
don't think gasoline dissolves epoxy, but that may depend on which type
was used.
Delamination: Was the plane kept inside? If so, massive
breakdown of the epoxy seems unlikely, although I have heard reports
that unfinished parts kept in damp places (?) can have problems. Too,
keep in mind that these are hand built airplanes. If the overall
craftsmanship looks good, it would still not be unusual for a couple of
spots to de-laminate (e.g. "missed a spot" when applying epoxy). I
found the attach point for the bell crank transfer actuator on the
elevator push rod delaminating, which would have caused a safety issue
if not repaired. The repair was simple - re-epoxy it and add an
additional layer of glass "just in case." However, the likelihood of
very large areas of delamination seems to be very small if the overall
quality is good - so a true safety of flight failure is fairly low.
Haven't heard of a single incident of such. IMHO I don't think there
is any possibility that poorly finished wing tanks (done by the
builder) could in anyway weaken the main spar (built in the factory).
Pump location: In my 235 they put the landing gear pump just
aft of the nose gear well, mounted vertically and difficult to access
(between you and your passengers' knees in flight). Some are in the
cargo area, or even behind the cargo area in the tail section. The
reservoir is very small, just holds a cup or two, and has a small
dipstick which also serves as the fill port at one corner. To fill you
will probably need a pump oiler (the old fashioned kind with a flexible
snout and about a half cup cylindrical screw on resevoir). Buy it just
for this purpose, they are cheap, and fit a 1/4" plastic tube extension
(about 10" long) on the tip. That will get you in about anywhere.
Brake fluid is fine, I forget the DOT number. Ask that question and
someone smarter than I will answer, it may also be posted in the
"files" section.
Squat switch: There is no squat switch preventing retraction
on the ground unless the builder added one. Adding one adds a possible
point of failure, either to prevent retraction or fail to extend
normally. While you do have emergency extension by dumping the
pressure (and should confirm routinely that it works), I personally
avoid lifting the handle on the ground. In my mis-spent youth flying
Phantoms they had such a switch, and a few hot rods were tempted to
raise the handle on the ground for "auto-retract" on takeoff (the
switch was on the mains). It failed, and they ended up resting on the
wing tanks.
Jacking procedure. There should be two very small holes about
1/4" deep x 1/4" diameter just forward of the leading inboard gear door
well. Most builders bought 2 cheap hydraulic bottle jacks
(http://www.northerntool.com/webapp/wcs/stores/servlet/category_6970_89+364+90555_0_13)
either tall enough to work without a base or built small boxes of 2"x4"
boards to raise the jacks about 10" off the floor. Barring that, you
can buy this kind with adjustable jack stands to do the trick (bottle
jack affixed to the top of the jack stand). The top of the jack (the
pad) screws in and out. Screw all the way in, slide the jack under the
hole, screw the pad out until the point sticks in the hole, confirm
that the pumping action of the jack will clear the gear door, and pump
until the main is about 3-4" off the ground. The nose wheel will be on
the ground still. Now, using several folds of towel as a cushion over
the "saddle" just forward of the vertical stab, run a strap or rope
over the towel and tie on weight sufficient to pull the nose up,
leaving enough free rope so you don't pull the tail down more than
necessary. Voila'.
Liability: There is not a single case of a builder being
successfully sued, and very few cases of lawsuits at all. To prevent
this, you can take the engine and instruments and wings (and maybe
more, but that might be enough) off the plane and de-certify. It then
becomes a kit in search of a buyer. The new buyer becomes the builder
and holds the repairman's certificate. Or so I am given to
understand. If you do this, take the opportunity to replace all the
plastic lines with metal and AN fittings. My 235 was destroyed because
a small electrical malfunction caused the seats to catch on fire, which
melted the fuel lines from the wings with predictable results. This
might have been avoided...
Fuel Gage: My 235 had a capacitance gage in the header; my 320
has a sight gage. I've had issues with both. Too, both the high and
low level float switches in my tank have failed. Neither plane had
wing gages. I plan to cut a hole in the rear of my header tank this
winter and create a removable port large enough to hold all of the
filler and vent lines; a capacitance gage; and float switches to
operate an automated transfer system (will upgrade the control switches
to On/Off/Auto). I will also install flow sensors to provide
indicators that fuel is in fact flowing, and to cut power to the pumps
when the supply is drained. Sensors like this one
(http://www.omega.com/pptst/LV170.html) are pricey, but very reliable
to sense out-of-fuel in the supply line. It may take me a try or two
to get it right, but I don't think it is an incredibly challenging
project.
Hope all of this helps.
Bill
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