Posted: Sat, May 19, 2012, 3:41 PM ET (1941 GMT)
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The launch of a privately-developed cargo spacecraft on a test flight to the International Space Station was scrubbed in the final second of the countdown early Saturday because of an engine problem. The Falcon 9 was to lift off from Cape Canaveral at 4:55 am EDT (0855 GMT) but computers stopped the launch at T-0.5 seconds, after the rocket's nine first-stage engines ignited but before liftoff. SpaceX officials said computers detected a "slightly high" combustion chamber pressure on engine 5, triggering the abort. Engineers will examine the engine to see if it can be readied for the next available launch window at 3:44 am EDT (0744 GMT) Tuesday. The rocket is carrying a Dragon cargo spacecraft on a test flight to maneuver around and berth with the ISS, allowing it, if successful, to make future cargo deliveries to the ISS.