This is a survey of the state of behavioral science knowledge related to long-term retention of flying skills completed for the U.S. Air Force (USAF). The report contains a survey of selected agencies and knowledgeable individuals as well as a literature review. (A list of libraries, agencies, and individuals consulted is appended, but a complete annotated bibliography was published separately.) The results of the review suggest that basic flight skills can be retained fairly well for extended periods of nonflying, but some decrement of concern does occur, particularly for instrument and procedural skills. Retraining of basic flying skills is judged not to be a major USAF problem, and much of the proficiency maintenance/retraining requirements can be met through the use of training devices and simulators. However, it is suggested that little is known about the retention, maintenance, and retraining of higher level pilot skills that characterize the USAF pilot in tactical units. Thus, recommendations are made for areas of further research that would help in the establishment of manpower management policies for the USAF pilot force. (BB)