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North American X-15A-2

Hypersonic Research Aircraft

The X-15 is a famous and significant part of aviation history. Its purpose was to fly high and fast, testing the machine and subjecting pilots to conditions that future astronauts would face. It made the first manned flights to the edges of space and was the world’s first piloted aircraft to reach hypersonic speeds, or more than five times the speed of sound. The X-15 was an important tool for developing spaceflight in the 1960s, and pilots flying above 50 miles altitude in the X-15 earned astronaut wings.

Three X-15s were built, and they made 199 flights between 1959-1968. The program was a joint U.S. Air Force/Navy/NASA project, and four of its 12 pilots were U.S. Air Force officers. One pilot, USAF Maj. Michael J. Adams, died in an X-15 crash in 1967. Another X-15 pilot, Neil Armstrong, later became the first man to walk on the moon.

Like other rocket planes, the X-15 was launched in midair from a B-52 “mothership” at about 45,000 feet. Once its powerful rocket ignited, the X-15 streaked upward to the limits of the atmosphere, then glided unpowered to land on a dry lake bed. Typical flights lasted about 10 minutes.

This aircraft is the second of the three X-15s. North American modified it for even greater speed, adding the large orange and white propellant tanks and lengthening the fuselage about 18 inches. This was the fastest X-15, reaching Mach 6.7 in October 1967. It was delivered to the museum in 1969.

TECHNICAL NOTES:
Crew: One
Engine: Reaction Motors XLR-99 of 50,000+ lbs. thrust
Maximum speed: 4,520 mph (Mach 6.7)
Ceiling: 354,200 feet (67 miles)

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