Measurement of Dynamic Reactions in Passenger Seat Legs

The dynamic impact test of a section of passenger airplane fuselage provided an opportunity to measure the loads transferred to an airplane floor by the passenger seat legs. Since placement of a force transducer between the seat legs and the aircraft floor could not be done without adversely affecting the validity of the measurements, it was necessary to develop an alternative instrumentation technique. The method chosen was to install strain gages on the legs of the seats and to calibrate the strain gage output in terms of forces transmitted to the floor of a rigid test fixture during sled tests of each seat. The instrumentation methods, the acquired data, and an analysis of the results of the calibration procedure are presented in this paper.