File:E-960.jpg

In the center of the photo is the B-47A (NACA 150/Air Force 49-1900). The B-47 jet bomber, with its thin, swept-back wings, and six podded engines, represented the state of the art in aircraft design in the early 1950s. The aircraft undertook a number of research activities between May 1953 and its 78th and final research flight on November 22, 1957. The tests showed that the aircraft had a buffeting problem at speeds above Mach 0.8. Among the pilots who flew the B-47 were later X-15 pilots Joe Walker, A. Scott Crossfield, John B. McKay, and Neil A. Armstrong.

On the right side of the B-47 is NACA's X-1 (Air Force 46-063). The second XS-1 aircraft built, it was fitted with a thicker wing than that on the first aircraft, which had exceeded Mach 1 on October 14, 1947. Flight research by NACA pilots indicated that this thicker wing produced 30 percent more drag at transonic speeds compared to the thinner wing on the first X-1. After a final flight on October 23, 1951, the aircraft was grounded due to the possibility of fatigue failure of the nitrogen spheres used to pressurize the fuel tanks. At the time of this photo, in 1953, the aircraft was in storage. In 1955, the aircraft was extensively modified, becoming the X-1E.

In front of the X-1 is the XF-92A (Air Force 46-682). Unlike the X-1 and D-558 aircraft, the XF-92A was not designed as a research aircraft, but as the prototype of a delta-wing fighter. While the effort was unsuccessful, the XF-92A offered the chance to test a delta wing aircraft. A brief series of 25 flights were made using the aircraft in 1953. These showed the aircraft had violent pitch-up tendencies during turns. Despite the problems, the XF-92A contributed to later delta wing aircraft, like the F-102, F-106, and B-58.

Behind the B-47, in the back of the hangar, are four other aircraft. From left to right, they are the second X-4 (Air Force 46-677) research aircraft. It was operated by the NACA from May 8, 1950, to March 22, 1954, when it left the High-Speed Flight Research Station for the U.S. Air Force Museum. It was designed to test the use of swept wings but no horizontal stabilizers. This proved to have poor transonic stability. Next to it is the ETF-51D Mustang (NACA 148/Air Force 44-84958) used for low-speed chase missions, as well as support and liaison flights. On the right side of the B-47 is the first D-558-1. Originally given the Navy number 37970, it was flown as part of the Douglas contractor program. When this was completed, the aircraft was turned over to the NACA on April 11, 1949. Although the aircraft was designation "NACA 140," it was never flown again. Instead, it was used to provide spare parts to keep the third D-558-1 in operation. In this photo the aircraft is partially disassembled.