For 5th Generation fighters such as the F-35, two-seat configurations are not available. Therefore, training relies heavily on ground simulators to prepare new pilots. Instructors have long noted that simulators have shortfalls in visual cues provided to the pilot, which are especially important for tasks where the pilot is required to visually maneuver the aircraft in relation to an outside object. One of the most obvious examples of this is aerial refueling, which has become increasingly important as 5th Generation aircraft tend to fly longer missions and in order to maintain stealth do not carry external fuel tanks. These two factors combine to drive much higher rates of aerial refueling. For single-seat fighter aircraft it is more difficult for new pilots to receive the necessary training given the absence of 3D cues in current simulators. The important visual cues for aerial refueling are stereopsis (different view to each eye) and head motion parallax (head movement to look around objects). An emerging class of light field displays offers a way to reproduce these cues at suitable fidelity. This paper discusses the requirements for a 5th Generation part task trainer with an emphasis on visual cues. Types and characteristics of different forms of 3D display are discussed with regard to their suitability for use in part task trainers. While it would be highly desirable to have true 3D displays in full-mission simulators, this could be extremely expensive and only useful for certain tasks. A part task trainer with a suitable 3D display could be extremely cost effective for training in such tasks as air-to-air refueling, takeoff and landing (in particular carrier landings), close air support, and extreme low level flight. Display requirements for a part task trainer able to simulate these situations are discussed.