Shuttle Endeavour readied for fueling (UPDATED)

Editor's note...
  • Posted at 09:28 AM EDT, 05/15/11: Forecast unchanged with 70 percent chance of good weather Monday
  • Updated at 10:20 AM EDT, 05/15/11: Updating launch time (2 second change)
  • Updated at 01:00 PM EDT, 05/15/11: Rotating service structure pulled away from shuttle
  • Updated at 04:35 PM EDT, 05/15/11: Thruster rain covers blow off; no impact to countdown
By WILLIAM HARWOOD
CBS News

KENNEDY SPACE CENTER, FL--Engineers prepared the shuttle Endeavour for fueling Sunday, setting the stage for blastoff Monday on a long-awaited space station assembly mission. Commander Mark Kelly's wife, Arizona Rep. Gabrielle Giffords, flew to the space center from Houston to await liftoff at 8:56:28 a.m. EDT (GMT-4) Monday.
The rotating service structure gantry at pad 39A was pulled away from the shuttle Endeavour Sunday, exposing the spacecraft to view and clearing the way for fueling. (Credit: NASA TV)

Forecasters are predicting a 70 percent chance of good weather. Storms rolled across the state overnight, but conditions improved as the morning wore on and engineers were cleared to retract a protective gantry from the shuttle a few minutes before noon to clear the way for fueling.

NASA television cameras focused on the nose of the orbiter showed protective rain covers over three rocket thruster nozzles pulled free in brisk winds, exposing the jets to the elements. Designed to pull away during launch, the Tyvek covers are intended to keep rain out of the nozzles before takeoff that could freeze and cause problems in orbit. But forecasters say rain is not expected before Monday's launch and the countdown proceeded toward fueling as planned.

The three-hour fueling procedure was scheduled to begin at 11:36 p.m. Kelly and his crewmates -- pilot Gregory H. Johnson, Michael Fincke, Gregory Chamitoff, Andrew Feustel and European Space Agency astronaut Roberto Vittori -- plan to start strapping in at 5:41 a.m. Monday to await liftoff on Endeavour's 25th and final flight.

Other than the missing Tyvek covers, there are no technical problems of any significance at pad 39A and forecasters are optimistic about the weather.

"The mid- and upper-atmosphere will dry out today, and there is only a slight chance for late afternoon thunderstorms associated with the west coast sea breeze," according to the forecast provided by the 45th Weather Squadron at Patrick Air Force Base. "Winds will decrease into the evening hours, and weather is favorable for tanking tonight. By launch time, the weather forecast is generally favorable, but the forecast wind speed and direction causes some concern for a Shuttle Landing Facility (SLF) crosswind violation. There is also just a slight concern for a low-cloud ceiling."

Protective covers over three maneuvering system thrusters in the nose of the shuttle pulled free in brisk winds after RSS retraction. (Credit: NASA TV)

A major problem during the early minutes of flight could force the crew to attempt an emergency return to the SLF and NASA flight rules require generally clear skies and crosswinds at or below 15 knots. The forecast for Monday calls for scattered clouds at 3,500 feet with winds out of 250 degrees at 10 knots with gusts to 15. Almost all of that is a crosswind on SLF runway 15/33.

The forecast for Tuesday calls for a 60 percent chance of a delay due to crosswinds, low clouds and rain, but the outlook improves to 80 percent "go" on Wednesday.