What Is a Fuel Gauge?
A fuel gauge refers to the component or system in vehicles or machinery powered by engines that informs the user about the remaining fuel quantity.
In the case of aircraft, until around 1950, fuel gauges were similar to those in cars, using a float in the fuel tank to measure the fuel level based on the position of the float. However, contemporary aircraft primarily employ the capacitance type, which measures the change in the static capacitance of a capacitor immersed in fuel.
Many aircraft have multiple fuel tanks and capacitance sensors are installed in each tank. Data collected from sensors in each fuel tank is processed by a computer for fuel calculations, displaying the remaining fuel for each tank and the overall aircraft fuel quantity.
Uses of Fuel Gauge
The aircraft’s fuel gauge displays the remaining fuel in pounds, a unit of weight. Pilots and on-board computers use the remaining fuel information to determine how much distance can be covered.
As fuel decreases during flight, the overall weight of the aircraft decreases. With a lighter aircraft, the potential altitude for ascent increases, allowing for higher cruising altitudes and more fuel-efficient flights.
Additionally, when there is a significant difference in fuel levels between the left and right fuel tanks, it can adversely affect the stability of the aircraft. Pilots monitor the fuel levels in each tank to maintain proper balance and stability during flight.
Therefore, the fuel gauge serves not only to inform about the remaining fuel but also to understand the aircraft’s weight and balance for optimal flight performance.