Hopefully will actually work this time.

Just returned from a flight to Mobile yesterday and back near
Jacksonville, FL today.  Was going to make my normal stop about 20 miles
south of the airpark for fuel, but after my decent I found that it was
broken at 3,000' and a thin scattered layer around 600' after showers
just moved through the area.  I made a non-eventful landing with the
normal electric boost pump on in downwind and turned off just after
landing.  During taxii back I noticed a fuel flow going way up and
stopping about 20 GPM.  Made a quick taxii for the hanger and noticed a
slight fuel smell so shut down quickly just before the hanger.  After
pulling it inside starter to take the cowl off and noticed a small fuel
puddle under the plane.  The builder of this plan was smart to put about
a 1/8" drain hole in the low part of the cowl to keep any leaking fuel
from pooling in the bottom of the cowl and I strongly recommend that
everyone do that.

After I got the cowl off I noticed that the copper fuel line that runs
from a fitting on the mechanical fuel pump to the firewall mounted fuel
pressure sender was broken off right where it comes out of the AN flare
fitting from the mechanical fuel pump.  A quick blip on the electric
boost pump that is right before the mechanical pump confirmed my fear
that it shoots out of the small hole inside the copper line like a
squirt gun and much of it winds up spraying on the exhaust pipe.  That
was enough to make me cringe.

I will admit that I did not look at the fuel pressure gauge during my
pre-landing check.  Skating around the low clouds on downwind had me
looking outside which was probably the best place for me to be looking
at the time.  Not sure if I would have seen the lack of pressure on the
gauge because I don't know if the break occured when I turned on the
boost pump or maybe right as I landed or during taxii.

It was a fairly smooth landing so I really don't that that small bump is
what broke the line.  I generally don't notice much of an increase in
fuel pressure with the electric pump on, but I do see an increase on the
flow meter from the pulsing of the pump.  I do regularly check for fuel
leaks in fuel system by turning on the boost pump while the engine is
not running and confirming that it holds pressure for several minutes
with no fuel flow showing on the meter after the pumps is shut off.  I
did that just a few weeks ago and thoroughly checked for leaks with the
electric pump on during the condition inspection, so might have been a
small crack leaking a bit, but not not for very long.  Anyway, I am
always looking at my fuel flow and it did not go up until just after
landing.

I am very thankful that the line did not break and start a fire in
flight.  Nothing like a small fuel line becoming a spraying blowtorch
with low ceilings and visibility.


Several lessons learned.

The solid copper line did have several loops in it to make it flexible,
but no more solid lines in the pressurized section of the fuel lines for
me.  It will be replaced with a flexible stainless armored aircraft fuel
line before the next flight with fire braid over it.  All my other fuel
lines are this way with the exception of the aluminum primer line, but
that line is not under constant pressure.  If I built this plane it
would have been that way from the start because I would have thought
about it when I installed it.  Being as it was already there I never
really thought about it.

I can't reach my fuel shutoff in flight without taking off the seatbelt.
 I had been planning on adding some type of remote actuation to the
lever.  That will be done before I leave for Oshkosh.  Been in a burning
aircraft on the ground before.  Don't want to be in a burning aircraft
in the air(nor on the ground again, but certainly not in the air).

Next time I notice a weird indication I will take action immediately.  I
should have shut down the engine and turned off the fuel as soon as I
noticed the high flow rate.  Taxiing back to the hanger thinking "hmmm,
flow meter acting funny again, but just flew 400 miles so plane must be
fine" was not the right move, especially when it would have been very
easy for me to walk a thousand feet to my house and tow the plane back
with my truck.

Hopefully others can learn something from this and prevent a story
without a happy ending.

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