Glad it all worked out well. My coupe has the glass tube enclosed
bobber wire and
I wasn't aware there was or should be a vent hole. Since I'm in a
wheelchair and
can't reach the header tank, can you tell me if and where the vent
hole is?
Thanks,
Dan
On Apr 7, 2009, at 7:25 AM, Glen Davis wrote:
Gang
I was ferrying N99828 from Florida to Mid Valley, Texas this past
weekend, delivering this beautifully restored Coupe to its new
owner. I had to make an emergency landing (in a farmers field) due
to a loss of power while at cruise. What I found should be a
lesson to all and an added item to everyone's pre-flight inspection
list.
I was at 1500 feet, 2450 RPM, mixture leaned. Weather was good
VFR. Right at the three hour point, I was only 12 minutes from my
next fuel stop. At this point, I expected my mains to be dry and
starting to use the 5 gallons in the header tank. As expected, the
fuel bobber in the header tank started to sink slightly. No
problem, I thought. I have one hour of fuel in that tank and only
12 minutes to my destination. In short order, I noticed by sound,
then by reading the tachometer, that I had lost 100 rpm. I gently
added throttle and brought it back up to 2450 RPM. Within a few
seconds, I noticed another drop in RPM, slightly more than the last
drop. I pulled the carb heat but did not notice much change except
the normal slight drop in RPM. That told me it was not carb ice.
At that point, I decided that I may lose all power at any point so
I pushed the mixture rich, the throttle full forward, initiated a
climb to get as much altitude as possible before the engine quite,
hit the nearest button on the 496 and turned toward the closest
airport, which was five miles away. The engine seemed to develop
full power in the climb and did not stumble. In about three
minutes I was at 4000 feet and according to the GPS, I was over the
private 2200 turf runway in about 4 minutes, at least according to
the GPS. I circled three or four times looking for the runway but
could not find it. I only saw farmers fields below me. There was
one long one that looked like a good place to land except for the
tractor right in the middle! I thought about flying to the next
closest airport but it was about 20 miles away and I didn’t know if
the engine was going to die. I decided to land on that long field
where the tractor was parked as there was enough room on one side
of the tractor for the Ercoupe pass by. The landing was successful
and the engine was still running. The farmer immediately came over
to see if I needed help. As it turns out, what I landed on was his
runway, but he had abandoned it as a runway years ago and now
leases it to another farmer. He made a few phone calls and was
able to reach an A&P mechanic who was willing to come out to help.
We spent about 3 hours looking at the fuel system, removing fuel
lines and checking for flow problems. None could be found. We
also checked the air filter to see if part of it was ingested into
the carburetor causing a partial blockage. There was no problem
there either. A called a few friends for ideas and one suggest
inspecting the fuel vents in the tank caps. I removed the header
tank cap and tried to blow through the vent. No air was passing
through the vent hole. We poked a wire through the vent hole and a
chunk of black goo came out the bottom. My guess it was a bug the
got smashed into the vent hole during the flight. I surmise that
while the main tanks had fuel in them, they were pressurizing the
header tank, keeping the fuel flowing. As soon as the mains went
dry, with the bug in the vent hole, the header tank became a
vacuum.... like holding your finger over a straw and lifting milk
out of a glass. I believe that the longer I flew using only the
fuel in the header tank, the worse the problem would have become.
The rest of the trip to Texas was uneventful, except for the winds
26, gusting 40, but that is another story.
The moral is check your fuel vents before you fly to make sure they
are not plugged up, especially the header tank. And, if possible,
always land with some fuel in the mains, just as a safety factor.
Glen
Glen Davis
917 297 1111
www.ishootpictures.com