X-3 Stiletto

The Douglas X-3 Stiletto was the sleekest of the early experimental Aircraft. Two X-3's were ordered but due to limited funding, lack of performance and on-going engine difficulties, only one (USAF S# 49-2892) was completed for flight, while the second was used for spare parts. The first aircraft was completed and delivered to Edwards Air Force Base, Calif., on September 11, 1952.
The official first flight was made on October 20, 1952. Following completion of contractor testing by Douglas Aircraft test pilot William Bridgeman in 1953, and a brief Air Force evaluation in 1953-54 by pilots Lt. Col. Frank Everest, Joseph Walker and Chuck Yeager, the X-3 was transferred to the National Advisory Committee for Aeronautics, with research pilot Joseph A. Walker of the High-Speed Flight Station (later: Dryden Flight Research Center) flying all 20 of its NACA research flights from 1954 to 1956. The X-3 did not approach its planned performance. Its first supersonic flight required that the airplane make a 15 degree dive to reach Mach 1.1. The X-3's fastest flight, made on July 28, 1953, reached Mach 1.208 in a 30 degree dive. Last flight was made on May 23, 1956. The aircraft was subsequently retired to the Air Force Museum.
Although the X-3 never met its intention of providing aerodynamic data in Mach 2 cruise, its short service was of value. It showed the dangers of roll coupling, and provided early flight test data on the phenomena. Its wing platform was used in the F-104, and it was one of the first aircraft to use titanium. Finally, the X-3's very high take off and landing speeds required improvements in tire technology.
In 1956 the X-3 was transferred to the U.S. Air Force Museum in Dayton Ohio.