Systems to determine gross weight and location of the center of gravity on transport airplanes have become commonplace and effective while operating in environments relatively known to the equipment designers. The system being proposed for the Boeing Supersonic Transport must operate at temperatures, accuracies, and functional capabilities exceeding that of equipment designed heretofore.Large aircraft of the Supersonic Transport configuration require precise determination of the longitudinal center of gravity prior to takeoff to assure economical and safe operation of the airplane. Requirements for the Boeing Supersonic airplane demand locating the center of gravity to within ±7.5 inches of the design center of gravity and gross weight to within ±0.5 percent of actual, including all mechanization errors. Sensors performing this task must operate in a temperature range of −55°F to +475°F.Further expansion capability for the system include the computation of gross weight and center of gravity in flight and the detection of vertical loads applied to the landing gear during the landing phase of a flight. The latter can serve as an indication of deceleration.