Developing the requirements and securing the funding for modern military aircraft can take a significant amount of time. Given emerging operational demands and the age of some current Air Force trainer aircraft, it is time to examine how the skills needed to perform future military missions might affect the capabilities required of new aircraft and ground-based systems used in pilot training. From 1962 until 1992, Air Force pilots learned to fly in an Undergraduate Pilot Training (UPT) program in which all students first flew the subsonic T-37 jet aircraft and then the supersonic T-38. In 1992 the Air Force began a transition to Specialized Undergraduate Pilot Training (SUPT), which tracked students after the T-37 phase of training. Students selected to fly fighters or bombers now train in the T-38, while those selected to fly tanker or transport aircraft train in the T-1A, a military derivative of a commercial business jet. The Air Force began replacing the T-37 with a new aircraft in 2001, but in the next few years, it must decide to replace or extend the lives of the aging T-38 and the newer, but tiring, T-1A. The timing of these decisions matters not only because the Air Force aircraft inventory will change dramatically in the next 25 years with the planned introduction of two new fighter aircraft and more unmanned combat aerial vehicles (UCAVs), but also because of changes in the demands of flying missions. Air Force pilots face a future characterized by around-the-clock global operations requiring near real-time implementation of airpower against an enemy, incorporation of precision weapons to increase mission effectiveness while minimizing exposure of manned aircraft to threats, mobility missions taking place closer to the enemy, integration of large amounts of information from disparate sources in real-time conditions, and flight profiles involving greater physiological demands. This monograph addresses the question of how the need to acquire skills necessary for future missions might affect what is taught in undergraduate flying training. It also addresses what impact the answer to this question has on decisions to replace or extend the lives of current Air Force trainer aircraft.