NASA to Study Valve Issue; Launch Uncertain

A troublesome fuel valve in the tail section of the space shuttle Discovery has forced NASA to delay the launch until Friday morning as they begin two days of tests and data collection.

Mission management team chairman Mike Moses addressed a few of us at 10:05 pm EDT tonight, "As we got into tanking we ran across a failure signal... the LH2 (liquid hydrogen) inboard fill and drain valve" did not indicate closure.

The valve is connected to a 8 inch duct line used to fill the hydrogen tank up for flight. The valves are changed out every 16 flights, and this flight of Discovery would be its 16th.

Mosses added, "When we went to close the valve, we did not get an indication that it went closed. You want the valve to go closed at launch." The launch team managers "really do think that this is telemetry" and not a huge valve replacement.

NASA has until August 30th to launch Discovery on her 14 day flight to the international space station. Beginning Wednesday night, mission management team members will begin accessing data on the valve and will formally meet at 12 noon EDT on Thursday to share and learn what they know.

If this valve issue cannot be addressed via the data the team collects, then NASA will likely postpone launch until mid-October due to a series of rocket launches to the space station during September, including a Japanese cargo carrier, a Russian cargo carrier and a human launch aboard a Russian Soyuz rocket.

As of tonight, NASA will target Discovery's launch for no earlier than Friday morning at 12:22:07 am.

The flight crew will stay here at Kennedy Space Center through Friday.