The Federal Aviation Administration is developing a computer modeling program (SOMLA--Seat Occupant Model: Light Aircraft) in an attempt to provide a practical engineering and design analysis tool for aircraft seat designers. To validate the model, two series of well-instrumented controlled tests have been completed by the FAA Civil Aeromedical Institute. These tests used two basic seat configurations, two different impact vector orientations, and two different impact levels to produce both elastic and plastic seat deformations. Measurements of seat reaction loads, seatbelt loads, and dummy accelerations were made, and the tests were documented by high-speed motion picture film. Each test condition was repeated to obtain a statistical measure of test variability. The results of these tests, and their implications regarding the development of the model, are presented.