X-Planes at NACA High-Speed Flight Station
The Dryden Flight Research Center, NASA's premier installation for aeronautical flight research, celebrated its 50th anniversary in 1996. Dryden is the "Center of Excellence" for atmospheric flight operations. The Center's charter is to research, develop, verify, and transfer advanced aeronautics, space, and related technologies. It is located at Edwards, Calif., on the western edge of the Mojave Desert, 80 miles north of Los Angeles.
Dryden's history dates back to the early fall of 1946, when a group of five aeronautical engineers arrived at what is now Edwards from the NACA's Langley Memorial Aeronautical Laboratory, Hampton, Va. Their goal was to prepare for the X-l supersonic research flights in a joint NACA-U.S. Army Air Forces-Bell Aircraft Corp. program. NACA–the National Advisory Committee for Aeronautics–was the predecessor of today's NASA.
Since the days of the X-l, the first aircraft to fly faster than the speed of sound, the installation has grown in size and significance and is associated with many important developments in aviation — supersonic and hypersonic flight, wingless lifting bodies, digital fly-by-wire, supercritical and forward-swept wings, and the space shuttles. Its name has changed many times over the years. From 14 November 1949 to 1 July 1954 it bore the name NACA High-Speed Flight Research Station.
Early X-planes posed at NACA High-Speed Flight Station (clockwise from bottom) Douglas D558-1, Douglas D-558-2, Northrop X-4, Convair XF-92A, and the Bell X-5. This group represents a wide variety of research programs, and only the D558-2 was a true high-speed airplane . [Bigger Image]
Equipped with Allison J-35-A-11 turbojet engine, The D-558-1 "Skystreak" was among the early transonic research airplanes. Three of the single-seat, straight-wing aircraft flew in a joint program involving NACA, the Navy-Marine Corps, and the Douglas Aircraft Company from 1947 to 1953. In the process, the Skystreaks set two world speed records.
Douglas pilot Eugene F. May flew the number one Skystreak for the first time on April 14, 1947, at Muroc Army Airfield (later renamed Edwards AFB). The goals of the program were to investigate the operation of a straight-wing configuration in the lower third of the transonic speed range (which extended from roughly 0.7 to 1.3 times the speed of sound) and to obtain data about flight in that speed range that were not available from existing wind tunnels.
When Commander Turner F. Caldwell set the world's speed record in the D-558-1 (NACA140), the Navy Bureau of Aeronautics stated in a message to the NACA, "A great measure of the credit for the success of the D-558 airplane speed record flight is due to the NACA. The highly important introductory research and investigation program leading to recommendations on airplane configuration problems was essential in the development of this airplane." 
The X-1E was the last rocket-powered X-Plane at the NACA High-Speed Flight Station until the arrival of the first three X-15s. [Larger Image]
Even though contemporary jet fighters could attain similar airspeed, the X-1E provided valuable rocket experience put to good use on the X-15 program .
I like the apparently casual attitude exhibited by the pilot and ground crew in this photo (I assume the guy with the hose is conducting some sort of non-volatile purge.) These guys had the best toys ever.
The X-1 and the D-558-II were among the very scarce sources of data on transonic flight conditions in the period 1947 to 1950 until the NACA developed better wind tunnels. These aircraft then contributed data to validate that derived from the tunnels by providing a reality check in the form of corresponding information from a real flight environment .
Convair XF-92A Dart
Douglas D-558-II Skyrocket
Douglas D-558-II Skystreak
F-104 Starfighter Chase Plane
Bell X-1 Rocket Planes
1. NASA Dryden Flight Research Center, D-558-I Skystreak Dec. 29, 2009
2. NASA Dryden Flight Research Center, D-558-I Fact Sheet
3. NASA, "X-15: Extending the Frontiers of Flight"
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