A comprehensive description of user problem definition for the PAN AIR (Panel Aerodynamics) system is given. The PAN AIR system solves the three dimensional linear integral equations of subsonic and supersonic flow. Influence coefficient methods are used which employ source and doublet panels as boundary surfaces. Both analysis and design boundary conditions can be used. The information needed to use the PAN AIR system is described. The structure and organization of PAN AIR are described, including the job control and module execution control languages for execution of the program system. The engineering input data are described, including the mathematical and physical modeling requirements.