Sunday, March 15, 2009

Launch Day: Discovery GO for Tonight


Following several days of repairs to the leaky gaseous hydrogen vent line - including the replacement of a valve - the Shuttle Management team are ready to go fly tonight and are confident the same leak will not reoccur which scrubbed Wednesday's launch attempt.

The hydrogen vent line runs from the launch pad to the space shuttle's external tank, and is the overboard vent to the pad and the flare stack where the vented hydrogen is burned off. "We're going to put this back together and go tank and if it doesn't leak we're going to be perfectly safe to go fly," stated Shuttle Launch Director Mike Leinbach on Saturday. "Technically we're exactly where we want to be. So we feel really good and really, really outstanding for a launch attempt [on Sunday]."

Discovery's twin solid rocket boosters should ignite at 7:43:46 pm EDT this evening, sending the space shuttle on a now shortened mission to the international space station. Spacelaunchnews.com will have LIVE television on our Homepage all day today and throught the mission.

The launch team will begin loading the external tank with its liquid oxygen & liquid hydrogen fuels at about 10:20 this morning. By around 11:45 am or so, the team should be able to know if the valve change out on the hydrogen vent line worked and if any gaseous leaks still exist.

If the launch team passes that milestone, then Discovery's seven astronauts will suit up in their partial pressure suits at about 3:25 pm EDT, followed by their departure to Launch Pad 39-A at 3:53 pm. Crew ingress of the Discovery would follow thirty minutes later, with Discovery's hatch being closed and sealed at about 5:40 pm.

This mission has been shortened from 15 days to about 13 due to a late-March Russian Soyuz manned flight to the space station. Mission operation state that two operating manned space craft cannot be docked to the station at one time due to their dynamics to the station. Also, the Soyuz will be bringing up a replacement station crew, known as Expedition 19, to replace the current Expedition 18 crew. Both crews will be involved with the week long complex handover, and Discovery's mission would be in the way.

No comments:

 
copyright 1998 - 2010 Charles Atkeison, SpaceLaunchNews.com. All rights reserved.