Trespassing Boats, Gusty Winds and Recalcitrant Valves… Oh My!

BY ANN Space Correspondent, Wes Oleszewski -- From The Cape

With crowds resembling those that gathered at the Kennedy Space Center for high-profile Shuttle Launches lining the roads and shoreline, the first Orion EFT launch attempt was scrubbed – but not without a lot of drama.

The first delay in the count came when a boat strayed into range safety’s restricted area.

Once the count resumed, the next hold was triggered by a gust of wind at the pad.

Reportedly, a mission rule that was programmed into the countdown computer was set to detect wind, blown from a given direction at a given velocity. Such wind is a hazard due to the wide cross-section of the launch vehicle. Once the countdown was recycled and started again, a second wind violation took place.

The process was repeated and restarted a third time when another wind violation took place. Upon that the launch directors elected to mask the wind limitation in the computer and make a manual judgment on the wind.
While the final wind decision was being made an issue was discovered with the Liquid Hydrogen (LH2) valve in the center CBC. As that valve was being exercised, and trouble shooting was taking place, a similar issue was detected in the port side CBC. These valves control the in-flow of the LH2 and once closed, are left in that position for the flight. Additionally, they can be used as a drain for the LH2. Each is a ball-valve that is more than 10 inches in diameter and located at the base of each CBC.

The count was recycled but the launch team decided to scrub the launch for the day as the launch window was about to close and no positive fix was found.

As of this writing a second attempt at launching the EFT-1 will take place Friday morning at 7:05 a.m. Eastern time. If, however, a 48 hour delay is required a Saturday Lunch will be attempted also at 7:05 a.m.

FMI: www.nasa.gov