Running dry?

Jay Honeck wrote:

In fact, I would never have guessed that this kind of a hair-brained
"fuel management" procedure would merit a serious discussion in these
newsgroups.

The fact that you consider it "hair-brained" does not make it so.

To even contemplate running a tank dry in the air, let alone propose
it as a standard -- even beneficial (?!) -- procedure, makes for
astonishing reading.

Huh. I've run my tanks dry on occasion, for a couple of reasons. First
of all, I wanted to calibrate my new fuel flow gauge. With 56 gallons
in the tanks (28 on each side), I ran one side dry and noted the fuel
used - good within 0.1 gallons out of 28 - I was happy. After I landed,
with 15 gallons left in the other tank (and with a fuel burn on that
trip of about 8.5 gal/hr) I still had almost a 2 hour reserve. It takes
me about 3 seconds to switch tanks, and I do so as soon as I hear the
engine start to stumble. It never stops firing, and it CERTAINLY never
stops rotating - not at 180 Kts TAS at 11.5K ft.

Plus, when I would run one tank dry BEFORE I had the FF gauge, it would
be the only time that I would know EXACTLY how much fuel I had left in
the plane. Seems like something worth knowing.

I'm totally confused as to what the dangerous part of this action might
be. The engine was running before - it'll run after 3 seconds of not
quite getting enough fuel. And since the prop doesn't stop turning (I
have to slow below about 90 Kts before that would happen), it starts
right back up as soon as the fuel returns.

Although this thread *does* answer a question that has bugged me for a
very long time. I've often wondered how it was possible that so many
NTSB reports ended with "fuel exhaustion" as an explanation.

Now I know.

I don't really think that you do. As I noted, I can run a tank dry and
have anywhere from 2.5 to 5 hours of fuel (depending on how fast I want
to go) left in the other side - that's hardly a "fuel exhaustion"
danger - some airplanes don't carry that much fuel when they take off
full.

--
Marc J. Zeitlin
http://www.cozybuilders.org/
Copyright (c) 2005