SR-71 SPECIFICATIONS & PERFORMANCE

The SR-71 was designed and built by the Lockheed Skunk Works, now the Lockheed Martin Skunk Works. SR-71s are
powered by two Pratt and Whitney J-58 axial-flow turbojets with afterburners, each producing 32,500 pounds of thrust.
Studies have shown that less than 20 percent of the total thrust used to fly at Mach 3 is produced by the basic engine itself.
The balance of the total thrust is produced by the unique design of the engine inlet and "moveable spike" system at the front
of the engine nacelles, and by the ejector nozzles at the exhaust which burn air compressed in the engine bypass system.

Speed of the aircraft is announced as Mach 3.2 -- more than 2000 mph (3218.68 kph). They have an unrefueled range of more
than 2000 miles (3218.68 kph) and fly at altitudes of over 85,000 feet (25908 m). As research platforms, the aircraft can
cruise at Mach 3 for more than one hour. For thermal experiments, this can produce heat soak temperatures of over 600
degrees (F).

The aircraft are 107.4 feet (32.73 m) long, have a wing span of 55.6 feet (16.94 m), and are l8.5 feet (5.63 m) high (ground
to the top of the rudders when parked). Gross takeoff weight is about 140,000 pounds (52253.83 kg), including a fuel weight
of 80,000 pounds (29859.33 kg).

The airframes are built almost entirely of titanium and titanium alloys to withstand heat generated by sustained Mach 3 flight.
Aerodynamic control surfaces consist of all-moving vertical tail surfaces above each engine nacelle, ailerons on the outer
wings, and elevators on the trailing edges between the engine exhaust nozzles.

The two SR-71s at Dryden have been assigned the following NASA tail numbers: NASA 844 (A model), military serial
64-17980, manufactured in July 1967, and NASA 831 (B model), military serial 64-17956, manufactured in September
1965. From 1991 through 1994, Dryden also had another "A" model, NASA 832, military serial 64-17971, manufactured in
October 1966. This aircraft was returned to the USAF inventory and was the first aircraft reactivated for USAF
reconnaissance purposes in 1995.

DEVELOPMENT HISTORY

The SR-71 was designed by a team of Lockheed personnel led by Clarence "Kelly" Johnson, at that time vice president of
the Lockheed's Advanced Development Company, commonly known as the "Skunk Works."

The basic design of the SR-71 and YF-12 aircraft originated in secrecy in the late l950's with the aircraft designation of
A-11. Its existence was publicly announced by President Lyndon Johnson on Feb. 29, 1964, when he announced that an A-11
had flown at sustained speeds of over 2000 mph during tests at Edwards AFB, CA. Development of the SR-71s from the A-
11 design, as strategic reconnaissance aircraft, began in February 1963. First flight of an SR-71 was on Dec. 22, 1964.

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