was not liked, the design concept clearly had promise and the delta wing was used on several Convair designs through the 1950s and 1960s. Of particular interest to aircraft designers was the unexpectedly good low-speed behavior Yeager had noticed on his second flight. The aircraft continued to remain controllable at very high angles of attack (alpha), where a conventional layout would have stalled. The reason for this turned out to be the unexpected creation of a large vortex over the top of the wing, generated by the airflow between the fuselage and leading edge of the wing at high alpha. The vortex became "attached" to the upper surface of the wing, supplying it with air moving at speeds much greater than the aircraft's forward speed. By controlling the flow in this critical area, the performance envelope of the delta could be greatly expanded, which led to the introduction of canards on most delta-wing designs in the 1960s and 1970s. More recently "mini-deltas", in the form of leading edge extensions, have become common on most fighter aircraft, creating the vortex over a more conventional wing planform. Aircraft on display 46-682 – Research & Development Gallery at the National Museum of the United States Air Force, Wright-Patterson Air Force Base, near Dayton, Ohio. Operators United States Air Force Specifications (XF-92A) Popular culture An unusual application of the XF-92A was as a movie model, stepping into the role of the "MiG-23" in the Howard Hughes film, Jet Pilot, starring John Wayne and Janet Leigh. Due to the lengthy delay in releasing the film, by the time it appeared in 1957, the XF-92A's role had been left on the cutting room floor. It did appear in the film Toward the Unknown (1956) starring William Holden, again in the guise of another aircraft, this time, the F-102 Delta Dagger. See also Notes Bibliography Bradley, Robert E. Convair Advanced Designs II, Crecy Publishing, 2013. Dorr, Robert F. and David Donald. Fighters of the United States Air Force. London: Temple, 1990. . Hallion, Richard P. "Convair's Delta Alpha". Air Enthusiast Quarterly, No. 2, n.d., pp. 177–185. Hallion, Richard P. "Lippisch, Gluhareff, and Jones: The Emergence of the Delta Planform and Origins of the Sweptwing in the United States", Aerospace Historian, Vol.26, No.1, Spring/March 1979. pp. 1–10. (JSTOR copy). Jenkins, Dennis R. and Tony R. Landis. Experimental & Prototype U.S. Air Force Jet Fighters. North Branch, Minnesota, USA: