Abstract: A fuel measuring system of the bubble type is adaptable for use with a plurality of tanks of predetermined differing geometries. The system employs at least two bubbling tubes located at predetermined locations in a tank. A predetermined volume flow of air is made to pass through each tube. Pressure transducers are used to periodically measure the air pressures supplied to the bubbling tubes. Temperature is also periodically sampled, and the pressure and temperature data is used by a microprocessor to make the necessary computations to first determine the averaged normalized air pressure and then the height of the fuel in the tank. In order to correlate the computed value of fuel height with the actual quantity of fuel in the tank, the microprocessor accesses data in a table lookup memory for the particular tank and performs calculations in order to derive the instantaneous volume of fuel in the tank.