Delamar Dry Lake in Nevada

Desert dry lake beds (also commonly called "playas," from the Spanish for "beach") are among the flattest and most extensive natural surfaces on Earth. Since the early 20th century, their flatness and extent have been exploited as courses for high-speed wheeled vehicles, such as with the land-speed records set on the Bonneville Salt Flats.

They also can serve as runways for aircraft, and were early used as emergency landing sites. Delamar Dry Lake, in particular, sits just north of what was to become the Nellis Bombing and Gunnery Range, and was designated an emergency landing site for military aircraft in 1943 during training for World War II.

Then came the X-15 rocket plane. This program is almost forgotten now, but it was the first venture into hypersonic flight with a crewed, winged aircraft to the edge of space. In fact, the Space Shuttle owes more to the X-15 program than to the Mercury through Apollo space capsule programs. The X-15 made nearly 200 flights from 1959 through 1968, setting some speed and altitude records that still stand, and several of the test pilots later received astronaut wings. (One of the test pilots was a then-unknown Neil Armstrong.)

The X-15 was carried to altitude under the wing of a modified B-52. When it was released the rocket engine would be fired and the mission would begin. The B-52 would take off from Edwards Air Force Base in California to various release points ("drop zones") over California and Nevada.

Emergency landing sites were especially important to the program, in case the rocket plane could not return to Edwards, and so some 50 dry lakes in California, Nevada, and Utah were surveyed as possibilities. They had to have exceptionally hard surfaces and be exceptionally long—Delamar Dry Lake fit the bill here too.

In May 1962, Armstrong landed a F-104 Starfighter chase plane on Delamar Dry Lake, in support of an X-15 mission, but the landing gear was damaged and he had to divert to Nellis Air Force Base outside Las Vegas. In May 1966, Delamar Dry Lake was used as an emergency landing site for X-15 flight 1-63-04 when the craft had engine failure.

The playa is no longer maintained as a designated emergency site. The old runway is now deeply rutted along its length, and would require significant refurbishment to make an acceptable airstrip.