When weighing an aircraft with full fuel tanks, which fuel quantity is not subtracted from the scale readings?

When weighing an aircraft with full fuel tanks, which fuel quantity is not subtracted from the scale readings?

• A. Usable fuel
• B. Unusable fuel
• C. Total fuel
• D. Fuel in the tanks after takeoff

Answer: (B)

When you weigh an airplane on scales, the reading includes everything that’s in the airplane at that moment, including all the fuel in the tanks. To determine the airplane’s weight devoid of fuel that will be burned before or during takeoff, you subtract the amount of fuel that is usable. The fuel that cannot be burned—unusable fuel—remains in the tanks regardless of flight conditions, so it is not subtracted from the scale readings. In other words, unusable fuel is effectively part of the fixed weight of the aircraft and stays with the airplane, whereas usable fuel is the portion you remove from the weight calculation.

When you weigh an airplane on scales, the reading includes everything that’s in the airplane at that moment, including all the fuel in the tanks. To determine the airplane’s weight devoid of fuel that will be burned before or during takeoff, you subtract the amount of fuel that is usable. The fuel that cannot be burned—unusable fuel—remains in the tanks regardless of flight conditions, so it is not subtracted from the scale readings. In other words, unusable fuel is effectively part of the fixed weight of the aircraft and stays with the airplane, whereas usable fuel is the portion you remove from the weight calculation.