Description of a model that provides a mechanism for testing the effects of a variety of policy variables on the structure of the USAF line officer force. The model produces counts of officers classified by component (AF Academy, Contract, Regular, Reserve), rating, grade, and year of service, and it also gives tables of "career flow", which show the flows into and out of each grade, by year, according to promotion, augmentation, and retirement. Input variables include yearly additions of academy graduates and contract officers, retention rates, parameters describing the promotion process, and totals of officers, regular officers, pilots, and navigators. This report describes the mathematical structure of the model and its inputs and outputs and also describes the Rand FORTRAN version. 70 pp. Ref.