The XLR-99 Pioneer rocket motor, manufactured by the Reaction Motors Division of the Thiokol Chemical Corporation, was the most powerful rocket engine ever installed on a piloted aircraft and was the most powerful man-rated (directly throttleable) rocket engine. This engine powered the fastest, highest flying aircraft ever built, the North American X-15. More than just a record setter, the X-15 performed scientific research which provided invaluable data toward the design of the Space Shuttle and advanced hypersonic flight.
Rated at 50,000 lb thrust, the engine had a single thrust chamber, fuel injector, gas generator, two-stage ignitor, turbopump, and variable controls. The fuels were anhydrous ammonia and liquid oxygen. This engine, Serial Number 108, powered a number of notable X-15 missions. For example, it was used on: NASA's first XLR99 mission (Flight No. 34); William Knight's (Flight No. 151), for which he became known as the "fastest man on earth" and; an "Astronaut Wings Flight" (Flight No. 153), a flight over 200,000 feet in which Joseph Engle earned his astronaut wings (even though the astronaut's vehicle was an aircraft).
Display Status
This object is on display in Nation of Speed at the National Air and Space Museum in Washington, DC.
Object Details
Date
1959
Country of Origin
United States of America
Type
PROPULSION-Rocket Engines
Manufacturer
Thiokol
Physical Description
60,000lb thrust; has a single thrust chamber, injector, gas generator, two-stage ignitor, turbo-pump, and variable governor control, and lime green thrust mounts; used liquid propellant; thrust chamber has been fired; missing fuel pump.
Dimensions
Overall (On stand): 588.8kg (1298lb.)
Overall: 40 1/4in., 910lb. (102.2cm, 412.8kg)
Other: 40 1/4 x 87 x 56 x 95 x 48in. (102.2 x 221 x 142.2 x 241.3 x 121.9cm)
Materials
Aluminum, Asbestos, Steel, Stainless steel, Nylon, Paint, Teflon, Plastic, Rubber (Silicone)
Inventory Number
A19930368000
Credit Line
Transferred from the U.S. Air Force Museum, Wright-Patterson AFB, Ohio. No known restrictions.
Data Source
National Air and Space Museum
Restrictions & Rights
Usage conditions apply
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