This is why you should never trust your fuel gages

Mike wrote:
"Dale Scroggins" wrote in message
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"Mike" nospam @ aol.com wrote in message
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"Dale Scroggins" wrote in message
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"Mike" nospam @ aol.com wrote in message
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"Ron Garret" wrote in message
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http://ronsvideos.fliggo.com/video/uIgc0dP9

This video was shot in a Cessna 206 taking us to a game reserve in
South
Africa. Watch the fuel gage in the upper right corner.

This is typical for a Cessna and a few others where the fuel gauge
uses the same technology as a toilet tank float.

A fuel totalizer is a very nice thing to have.

Float-type sending units are, in fact, simpler than toilet tank
float valves, and more reliable. They work reliably for decades.
However, many have been in service nearly forty years. Eventually
the resistance winding will develop spots where the wiper doesn't
make good contact, and the gauge (U.S.) or gage (Brit.) will
fluctuate wildly for a few minutes, until fuel is burned off and the
wiper moves to a new location, then the gauge works normally again.
Simple and relatively simple to fix.

If what you say is true, why do quite a few relatively new planes
exhibit the same symptoms?


Do you believe fuel totalizers are more reliable? Or capacitance
systems? Do you trust totalizers totally?

I've flown lots of planes with totalizers and never seen a failure.
I've also seen lots of failures and gross errors in float type
systems (new and old), so in my experience, yes they are more reliable.

As far as your last question it appears to be argumentative. I could
just as easily ask you if you trust the standard Cessna fuel gauge
totally, but neither really deserves an answer.
I doubt my experiences are typical. Most of the fuel quantity and
totalizer systems I saw over thirty years weren't operating correctly,
and I was being paid to repair them. Age makes most indicating
systems untrustworthy. Having multiple systems is good, if they aren't
interdependent.

Agreed, and the best way to check them is simply to stick the tanks both
before and after a flight.

Even float rods on Piper Cubs and others hang occasional, or the
floats saturate and sink. Direct-reading sight tubes are probably
the most reliable indicators, but even those can become difficult to
read with age.

I don't trust any fuel indication system.

There is one fuel indication system that's reasonably accurate, and that
is the prop which quits turning when you run out. Where many people get
into trouble is they DON'T trust their fuel indication system until the
aforementioned one indicates zero. I use mine to cross check my flight
planning, and if they don't agree it's time to do something different.

I like my engine performance tables and a stop watch, Pretty accurate.

--

Regards, Ross
C-172F 180HP
KSWI