Visual determination of fuel on board

[Ernie Martin]

You use a dip tube which you calibrate per the instructions with the tube. It won't register below roughly 1/2 full, but it's quite accurate above that. In my 1973 normally aspirated 337E with long range tanks, a thin film visible under the fill port indicates you have 30 gallons in the tank (max 62). Greater fills can be accurately guaged with the tube.

Ernie