Posted: Sun, Dec 6, 2015, 9:59 AM ET (1459 GMT)
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DARPA has scrapped plans to launch small satellites from a fighter jet. The Airborne Launch Assist Space Access (ALASA) program, under a contract with Boeing, planned to develop a rocket deployed from an F-15 for launching small satellites. The rocket used a unique propellant, a mixture of nitrous oxide and acetylene, but that propellant exploded in ground tests earlier this year, raising questions about its safety. DARPA has now dropped plans to perform up to a dozen launches of the ALASA vehicle, and will instead continue tests of the propellant and other technologies.