NASA will try launching its uncrewed Orion space vehicle Friday morning after scrubbing Thursday’s launch due to mechanical issues, according to a post on the civil space agency’s blog.
The launch window will open at 7:05 a.m. EST and will last roughly 2.5 hours, same as Thursday. Fill-and-drain valves on the United Launch Alliance (ULA) Delta IV Heavy launch vehicle were to be tested throughout Thursday so the launch team can prevent a mechanical problem like the one that came up Thursday morning.
The valves that failed to close properly late in the countdown allow liquid hydrogen to flow into the three core boosters of the first stage. Normal operation calls for the valves to stay open during the fueling and shut tight a few minutes before liftoff to seal the fuel tank.
The weather for Friday is forecast to be a bit worse than Thursday, NASA said, though still favorable. Meteorologists are calling for a 60 percent change of acceptable conditions. Launch will take place at Cape Canaveral Air Force Station, Fla.
During its 4.5-hour trip, formally known as Exploration Flight Test-1 (EFT-1), Orion will orbit Earth twice and travel to an altitude of 3,600 miles into space. The flight test is designed to test many of the elements that pose the greatest risk to astronauts and will provide critical data needed to improve Orion’s design and reduce risks to future mission crews. Mike Hawes, Orion program manager for prime contractor Lockheed Martin [LMT], said earlier this week the test flight is to evaluate critical technologies not just in the low-earth orbit (LEO), but farther out (Defense Daily, Dec. 2).
ULA’s Delta IV Heavy configuration features three RS-68 engine cores plus a RL-10B2 second stage, all developed by Aerojet Rocketdyne. ULA is a joint venture of Lockheed Martin and Boeing [BA]. Aerojet Rocketdyne is a division of GenCorp [GY].