Computer Code for the Determination of Ejection Seat/Man Aerodynamic Parameters.

Abstract : The first phase of an effort concerning adaptation of Mark IV computer program (1) as an engineering tool to be used in day-by-day design and development work by the members of Air Crew Escape Group (AFWAL/FIER) was carried out. This research effort consisted of the following two parts: (1) modeling the ejection seat/man configuration, namely, representing its surface with a finite number of rectangular elements and inputting the geometry data of the model into the computer in a format acceptable to the Mark IV computer program, (2) computing the six aerodynamic coefficients using an appropriate pressure law option provided by the Mark IV computer program, and comparing the values predicted by the computer with those obtained from wind tunnel test. A total of five computer models patterned after the models used in wind tunnel test were created. Aerodynamic coefficients were computed for each model over an angle-of-attack range of -40 to 60 degrees and a yaw angle range of 0 to 30 degrees. By adjusting various factors which affect the outcome of computation, an attempt was made to identify an optimum computation method. (Author)