Note: This item is currently in storage.
The advent of small jet-propelled aircraft challenged engine manufacturers to provide propulsion systems for them. When an engine was required to propel unmanned aircraft, such as the AGM-136A Tacit Rainbow, on a one-way trip to a target, they faced the added challenge of designing a "throwaway" engine. It had to have a long "shelf-life" but a short life expectancy -- once started -- of about three hours. Williams International responded with the F-121, one of the smallest engines of its type ever built and flown in an aircraft.
The F-121 first flew in an AGM-136A on July 30, 1984. Since the engine could not be started until after the vehicle left its parent aircraft, it had a pyrotechnic (cartridge) starter. Flight test experience proved it to be a relatively trouble-free engine. Out of 32 free-flight test missions, not one was impaired by an F-121 engine problem.
While the display engine obviously never flew a Tacit Rainbow test mission, it was used in many "bench" tests before being retired to the museum in February 1993.
8 1/2 in.
Fan by-pass ratio:
Approx. 70 lbs. at 45,000 rpm
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|Northrop AGM-136A Tacit Rainbow
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