With the final flight on Aug. 26, 1949, the aircraft was turned over to the Air Force for Phase II testing by Maj. Charles E. “Chuck” Yeager. The aircraft was given the Air Force designation XF-92A, and carried the serial number 46-692. Although the aircraft carried the designation of a prototype fighter, its role was now that of research aircraft. The Phase II flights were tests by Air Force pilots to see if the aircraft met the contract specifications. The first Phase II flight was made by Yeager on Oct. 13, 1949. (A day short of two years after his Mach 1 flight.) The tests were completed with a final flight on Dec. 28, 1949, by Maj. Frank Everest [3].

After the Air Force’s plans for an interceptor failed to materialize, the NACA High-Speed Flight Research Station, which had supplied engineering, instrumentation, and operational assistance to the Air Force during its flights, took over the flight test program in 1953.

A. Scott Crossfield was the NACA pilot selected for the XF-92A research flights. His introduction to the aircraft, during a taxi across the lakebed, was memorable. He recalled years later, “Nobody wanted to fly the XF-92. There was no lineup of pilots for that airplane. It was a miserable flying beast.” Before the taxi, Everest briefed Crossfield, who recalled, “He told me, ‘Keep the nose up so it will slow down. Because it will roll a long ways.’ Well, I let the nose come down and on the nose wheel. I couldn’t get it back up. It didn’t have enough tail power to do it. So that airplane was rolling like mad towards the edge of the lakebed…. I saw a county road off to the left. And I managed to get that thing turned and head up that country road. Burned out the brakes. Just melted them right there. Rolled up that county road about 100 yards. And fortunately no damage to the airplane. Came out pretty well, except the brakes were all burned out.” The road was later named “Crossfield Pike.”

Crossfield flew a total of 25 flights in the XF-92A between April 9, 1953 and Oct. 14, 1953. The initial 13 flights were for data on static longitudinal stability; dynamic stability; directional control; longitudinal and lateral stability and control, and low speed stability and control. These were followed by 10 flights to test different wing fence configurations. The wing fences were designed to control the tendency of swept wing aircraft to pitch up at low speeds and in turns. The initial six flights were made at speeds under Mach 1. The last four were for data on low-speed lateral and directional control with the wing fences. On one flight, the modified wing fences buckled during the test. The XF-92A undertook two low-speed lateral and directional control flights without the wing fences. These were both made on Oct. 14, 1953. When the XF-92A landed on the lakebed after the second flight, its nose gear collapsed. Crossfield was unharmed, but the XF-92A never flew again. The Air Force subsequently donated the XF-92A to the University of the South in Sewanee, Tenn. The aircraft was transferred to the Air Force Museum in 1969, where it is now on display [3].

Besides validating the thin delta wing principle, the XF-92A played a major role in supporting the development of the Convair F-102A interceptor, the Air Force’s first attempt at an all-weather, supersonic interceptor. In 1953, the XF-92A experienced a landing gear failure on rollout after landing at the NACA High-Speed Research Station and the aircraft was retired [1,2].