Tuesday, August 04, 2009

Watch It Live: Discovery Slogs Toward Launch Pad

BLOGGER UPDATE: 12:52 PM: Discovery just pulled up onto Kennedy Space Center's launch pad 39A as NASA races to get the shuttle in place before seasonal summer afternoon thunderstorms sweep through the area. The shuttle's mobile launcher platform now is being fixed to six pedestals and should be "hard-down" between 1:30 p.m. and 2 p.m. The weather forecast for the KSC area calls for a 60 percent chance of thunderstorms and lightning between 3 p.m. and 7 p.m. The shuttle is protected at the pad by a lightning mast that juts up from the Fixed Service Structure and an associated catenary wire system. The Rotating Service Structure will be rolled back around the vehicle this afternoon to provide weather protection and access to the shuttle.

It's slow-going for Discovery at Kennedy Space Center today as the shuttle makes its way over a soggy crawlerway toward launch pad 39A, where it is slated to blast off around Aug. 25 on an International Space Station outfitting mission.

Mounted atop a mobile launcher platform, the shuttle is being hauled to the pad by a crawler-transporter that once moved huge Saturn 5 moon rockets out of the KSC Vehicle Assembly Building. The wet conditions are prompting a slow, 0.3 mph move. Normal speed for rollout is around one mph.

The river-rock road was deluged during thunderstorms that doused the KSC area on Monday. Lightning held up the start of the move -- which had been slated for 12:01 a.m. -- until 2:07 a.m.

Crawler drivers have been stopping every so often to clean mud from the transporter's cleats and bearings.

The 3.5-mile move to pad 39A usually takes about six to seven hours to complete. NASA is keeping close track on the weather. The forecast calls for a 60 percent chance of thunderstorms and lightning in the area between 3 p.m. and 7 p.m. today. NASA aims to have the shuttle on the pad and enveloped by the Rotating Service Structure there before the storms begin.

Stephanie Stilson, the NASA Flow Manager for Discovery, tells Florida Today that the earliest the shuttle could launch is Aug. 24. However, that assumes repair work on the shuttle's lefthand solid rocket booster steering system can be completed in parallel with other routine launch preparations.

NASA is facing an end-of-the-month deadline to launch Discovery.

The agency wants to launch, complete the outfitting mission and depart the station before the debut launch Sept. 10 of a Japanese HTV cargo carrier. NASA officials have said they will yield to the HTV launch and slip Discovery until later in September if the shuttle is not off the ground by Aug. 30.

NASA might gain a few extra launch attempts in early September if program managers cut content from the shuttle mission.

Stilson said she remains confident that Discovery will be ready to launch later this month despite a one-day delay in the rollout to pad 39A.

NASA engineers discovered a faulty check valve in the shuttle booster steering system during routine testing on Saturday. The valve will be swapped out at the pad later today and NASA also intends to remove and replace the Auxiliary Power Units and hydraulic pump assembly from the steering system.

You can watch the ongoing rollout live here in The Flame Trench. Simply click the NASA TV box on the right side of the page to launch our NASA TV viewer and be sure to refresh this page for periodic updates.

3 comments:

Mark Lopa said...

Why the delay in bringing the RSS around Discovery? It looks like it's still retracted open.

Todd Halvorson said...

NASA has an APU hot-fire scheduled at the pad this AM, and that's an RSS-open operation. A hot-fire is required if an APU is new, or newly refurbished, so the plan is to retract the RSS once that test is done. The big rush yesterday was to get the vehicle on the pad structure, where it is protected by the lightning mast and the catenary wires. The RSS, of course, does provide weather protection also...

Anonymous said...

Wow, did you see the close up views of the Discovery on the way to 39-A? Talk about a smudgy-looking spacecraft.

You'd think that with all the money, just rolling in from the Obama administration, someone could get up there with a couple of Magic-Wipes and clean off some of that Carbon soot from the white tiles.

Rick Steele
Sarasota