NASA Expendable Launch Vehicle Status Report 17 July 2006

Mission: STEREO (Solar Terrestrial Relations Observatory)
Launch Pad: 17-B, Cape Canaveral Air Force Station
Launch Vehicle: Boeing Delta II
Launch Date: No earlier than Aug. 20, 2006
Launch Time: 3:52 – 4:07 p.m. EDT

At the Astrotech Space Operations Facility, STEREO was moved to the hazardous processing facility early last week for fueling, stacking and spin-testing of the two observatories. During fueling of Observatory A, one of the valves used to load the spacecraft with hydrazine propellant was observed to be leaking from a secondary seal. Technicians suspended the fueling and made adjustments to the fuel line connection. Fueling operations resumed with no further leakage. Both observatories are now completely fueled. However, as a precaution, the two observatories have not been pressurized while this problem is investigated. An anomaly team is working to fully determine the reason for the problem and assess the integrity of the valve.

For this reason, launch has been rescheduled for the opening of the next launch window, no earlier than Aug. 20.

At Pad 17-B, the Delta II second stage was stacked atop the first stage on July 13. The following day, the payload fairing was hoisted into the pad cleanroom located at the upper levels of the mobile service tower. Technicians are now performing standard prelaunch electrical interface testing of the two stages and checking the guidance system.

For previous expendable launch vehicle processing status reports, visit:

http://www.nasa.gov/centers/kennedy/launchingrockets/status/2006