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REFLECTOR: Fuel Porting Engine Out Landing

Last Friday I had the fortunate circumstance of succesfully gliding my
Velocity into an airport after the engine quit do to fuel starvation.  The
problem was only the pilot side tank was draining while the copilot side
tank remained full.  The scenario was that I was on a 2 hour flight when
suddenly I noticed that my westach capacitance guage was reading 3/8 on the
pilot side. So, I looked over my shoulder and verified that the pilot sight
guage read the same. I had 3/4 full on the copilot side.  I thought it
strange that the copilot side did not balance out to the pilot side at
least somewhat balanced.  So, I reversed course and circled a 9000' runway
for 15 minutes to see if banking the wing on the copilot side would
force/gravity feed the fuel into the pilot side.  It didn't, then I
surmised that since I had only been flying 1 hour and had recently flown
many 2 hour flights that maybe the fuel will start pulling from the copilot
side at some point when the pilot side is down low due to wind direction
and speed into the vents causing minor venturis at the openings.  Next, I
decided to play it safe and head for my home base about 30 miles away.  I
was at 7000' and had to descend under 4000' to stay out of the TCA veil.
When 10 miles away from home base I decided to swing over the closest
airport to me somewhat out of the way to home base but shorter distance and
then transition directly to the home base over the top at 2500' so that I
would be able to glide from any point if the engine did stop.  No sooner
than I made that decision and turned slightly toward the other airport than
the engine coughed once and quit at 2700' AGL and 5-7 miles out (best
guess).  I trimmed nose up to 80-85 knots resulting in 700-800 fpm descent
rate.  I was facing a 15 knot direct headwind.  I prayed. And thanks to the
superb glide ratio of the Velocity and a lot of help from the Almighty, I
just made the threshold of the runway.  And this glide ratio was one of the
main reasons,  I decided to build the Velocity.
I checked the fuel caps to see that they had a good seal (rubber O rings
were lubricated and not dried out) and they were fine.  Joe (Doc) Connally
and I worked a .032 safety wire up both tanks vents and on the tank that
didn't drain, there was a crunchy sound about 5 inches up the tube.  I
worked thru it and pulled the wire out and there was crap on it.  Then, Doc
blew on the tank opening while I watched the tube and out came a spurt of
what looked like dirt.  Voila, the culprit was identified.  You know I blew
into those vents like 2 days prior to the incident to make sure they worked
and they were ok.  The high speed must have compacted the insect/wasp nest
blockage tight enough to totally block airflow during the flight.  I guess
it should be a standard pre-flight item to blow on the tubes.  Anyway, I am
buying small children's nylon hose to stretch over the vent housing with
18" REMOVE BEFORE FLIGHT streamers.  Even if I forgot to remove them the
nylon would breath.  In talking to Doc and Mike Pollack, for those with the
Naca type vents, a cover that would still breathe for fuel expansion would
be to take a piece of pipe cleaner and cut it off about 4" long. Then, make
a small loop on one end and attach a REMOVE BEFORE FLIGHT streamer.  Make a
small round aluminum circle that covers the Naca opening out of thin
aluminum.  Drill a small hole in the center and slide it over the pipe
cleaner up to the loop.  Cut the open end of the cleaner to the desired
length to fit up into the vent tube and hold the cover in place.  This will
cover the Naca outlet keeping pests and dirt out but allow air to breath
thru the pipe cleaner bristles.

Greg Otto
Velocity STD FG