Aeronautical Terms beginning with R

Ramp Weight

The zero fuel weight plus all of the usable fuel on board.

Reference Datum

(GAMA) An imaginary vertical plane from which all horizontal distances are measured for balance purpose.

Reduction Factor

A number, usually 100 or 1,000 by which a moment is divided to produce a smaller number that is less likely to cause mathematical errors when computing the center of gravity.

Residual Fuel

Fuel that remains trapped in the system after draining the fuel from the aircraft with the aircraft in level flight attitude. The weight of this residual fuel is counted as part of the empty weight of the aircraft.