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[i]John Mulholland, vice president and program manager for the Starliner program at Boeing, said the Starliner software is intended to initialize its mission elapsed timer from the Atlas 5 launch vehicle, but only in the "terminal count" phase of the countdown. The software, he said, lacked that terminal count requirement. "So, it polled an incorrect mission elapsed time from the launch vehicle, which then gave us an 11-hour mismatch," he said. The second problem, revealed Feb. 6 at a meeting of the Aerospace Safety Advisory Panel (ASAP), was a "valve mapping error" for the thrusters in the vehicle's service module. Those thrusters perform a "disposal burn" of the service module after separating from the crew module just before reentry. Mulholland said the valves were configured for conditions in normal flight for that disposal burn, which, had it not been corrected, could have pushed the service module into the crew module. That could have caused the crew capsule to become unstable, requiring additional thruster firings to reorient itself, or have damaged the capsule's heat shield. The second error was detected during the review of the spacecraft software on the ground after the timer problem took place. Mulholland said engineers found the thruster software issue late Dec. 21, with the corrected and reverified code uploaded to the spacecraft around 5 a.m. Eastern Dec. 22, or about three hours before the spacecraft landed at White Sands Missile Range in New Mexico.[/i]
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