JS blocked

Delta IV issues, Winds Scrub Orion's Exploration Flight Test-1 Debut


NASA on Dec. 4 scrubbed its first attempt to launch Exploration Flight Test-1, the planned two-orbit, 4.5-hr. debut of the Orion crew exploration capsule, after surface winds at the Cape Canaveral Air Force Station, Florida, launch site exceeded safety limits and difficulties with propellant valves on the Delta IV launch vehicle surfaced late in the countdown.

A second launch attempt was tentatively scheduled for Friday at 7:05 a.m. EST.

Efforts to lift off before Thursday's 159-min. launch window closed at 9:44 a.m. EST, were called off at 9:34 a.m. EST.

After a second hold prior to the planned 7:05 a.m. EST liftoff in response to northerly wind gusts exceeding a 24 mph safety limit, the United Launch Alliance launch team encountered difficulties with the cycling of liquid hydrogen fill and drain valves on the Delta IV's first stage left and center cores.

The troubleshooting continued until there was no longer time to lift off within Thursday's window, which closed at 9:44 a.m. EST. Concerns over adequate battery power for cameras on the launch vehicle also were a factor.

Friday's weather outlook for a similar launch window was not favorable. U.S. Air Force forecasters called for a 70% chance of a weather constraint violation from rain showers, cloud cover or surface winds.

A similar launch window for Saturday opens at 7:10 a.m. EST.

Please or Register to post comments.

What's On Space?

On Space

Blog Archive
We use cookies to improve your website experience. To learn about our use of cookies and how you can manage your cookie settings, please see our Cookie Policy. By continuing to use the website, you consent to our use of cookies.