Friday, August 21, 2009

Live at KSC: Discovery on track for countdown

The countdown to space shuttle Discovery's early Tuesday launch is on track to start at 11 p.m. today at Kennedy Space Center.

"As of the moment, our systems are in good shape, launch countdown preps are proceeding without much event and we have no new issues to report," NASA Test Director Steve Payne said during a news briefing this morning at KSC. "The flight crew, the vehicle and the launch team are ready to go."

Discovery and seven astronauts plan to blast off at 1:36 a.m. Tuesday, in the middle of a 10-minute launch window.

Their mission to haul more than seven tons of supplies and experiments to the International Space Station is scheduled to last 13 days, but could be extended a day if necessary.

Spaceport workers today are finishing pressurization of Discovery's Main Propulsion System and Orbital Maneuvering System high pressure tanks, a hazardous operation that should be complete around 1 p.m., Payne said.

Retests of a couple minor repairs will extend beyond the start of the countdown, but shouldn't become issues, Payne said.

Those include an engine harness replaced Thursday and a hydraulic power unit replaced on the shuttle's left-hand solid rocket booster.

Mission managers must clear one final item during a meeting planned Sunday: the failure of a device that switches power on and off to various shuttle systems.

Workers replaced the device last week, but analysis continued to better understand the failure and be sure that another wouldn't pose a problem during flight.

Payne said there is "pretty high confidence" that the unit is sound and unlikely to interrupt the launch schedule.

Launch teams will be called to their stations at 10:30 p.m. Thirty minutes later, countdown clocks are set to start ticking down from T minus 43 hours.

The forecast for Tuesday is favorable, with a 70 percent chance of good launch weather.

If the launch is delayed, the forecast remains 70 percent "go" on Wednesday, when liftoff would be at 1:10 a.m., and 60 percent "go" on Thursday, when liftoff would be at 12:47 a.m.

"It's actually pretty decent weather," Payne said.

If need be, Discovery can make four launch attempts in five days. The launch window runs through Aug. 30.

After that, the mission would likely be delayed until October because of two other spacecraft visiting the station next month - an unmanned Japanese cargo vehicle making its first flight and a Russian Soyuz carrying up three new station crew members.

1 comment:

Anonymous said...

The space industry needs to improve on pr. This doesn't excite the majority of non-space industry personnel. At least not enough to justify a budget increase for the gov't run space program. Lottery off tickets to the moon or something!