Piloted by A. Scott Crossfield, on November 20, 1953, the Douglas D-558-2 Skyrocket became the first aircraft
to fly faster than Mach 2, twice the speed of sound. Air-launched from a U.S. Navy Boeing P2B-1S (B-29) the swept-wing, rocket-powered
D-558-2 reached Mach 2.005 in a shallow dive at 18,898 meters (62,000 feet).
The D-558 series of aircraft was developed by Douglas under the direction of Edward H. Heinemann for the U.S. Navy to explore transonic
and supersonic flight. The National Advisory Committee for Aeronautics (NACA, the predecessor to NASA), used this Skyrocket,
the second one built, to explore the flight characteristics of swept-wing aircraft. It set several other speed and altitude records
before the program ended in 1956.