Little Joe was a solid-fueled booster developed for Project Mercury and launched eight times from Wallops Island between 1959 and 1960 to test spacecraft systems, particularly the launch-escape system and heat shield. As one of the first launch vehicles designed specifically for crewed-spacecraft qualification, it pioneered the use of clustered rocket motors. Its successor, Little Joe II, was used from 1963 to 1966 to test the Apollo launch-escape system.
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| A Little Joe Booster cover from "Goldcraft", postmarked at Wallops Island with a hand cancel on January 18, 1960, three days before the successful Little Joe 1B (LJ-1B) Mercury abort test. |
The main purpose of the Little Joe booster was to provide a simple, low-cost means of conducting repeated Mercury tests, particularly of the spacecraft’s launch-escape system and aerodynamic behavior. Its solid-propellant motors, proven components, and lack of electronic guidance kept the system inexpensive and quick to develop.
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| Photo: The design of the Goldcraft cachet may have been inspired by this mock-up of the Project Mercury space capsule, which was used to train astronauts in techniques for exiting the capsule. |
Little Joe was designed to approximate the performance of a Redstone booster with a Mercury capsule, but at about one-fifth the basic cost, with lower operating expenses. Its small size also allowed launches from the existing Wallops Island facilities, making frequent testing practical.
(Reference from
Little Joe (rocket))
