Peter R. wrote in message ...
NoSpam wrote:

Is there a way to ACCURATELY measure the available fuel in the tanks of a
general single-engine piston aircraft???

Just after receiving my private pilot certificate, I bought a FuelHawk
to accurately measure remaining fuel in my Skyhawk's tanks:

http://makeashorterlink.com/?O202128F6
...
I would be very uncomfortable flying one of these missions without it.

Peter,

I would be very uncomfortable relying on that FuelHawk unless you
have personally calibrated it in your plane and know it to be accurate.
We used to rent C172s, we had a FuelHawk, and the reading would be
different in different tanks which had the same amount of fuel left
as judged by how much fuel was added to 'top off', even different tanks
in the same plane.

I think Greg Travis posted a similar observation regarding his 180 HP
C172.

When we bought our Grumman, we calibrated the FuelHawk by noting the
reading before each top-off then doing a polynomial fit once we got
enough readings across the range. The other method of course is to
fly one tank dry then pour in fuel 1 gallon at a time, taking due
precautions against static. The latter method is quicker, both methods
are quite accurate if carefully done.

Once the stick (any stick -- fuel hawk, paint stirrer, etc) is
calibrated, it is quite accurate and I recommend it even to people
who always take off with full tanks, to determine whether they
actually landed with the amount of time in the tanks that they
thought they had. This has been a revelation to us a couple of
times (though, when the tank under the stick is dry, I still have
between 0 and 14 gallons, just our tank design).

Cheers,
Sydney