While the shuttle Endeavour's crew reviewed emergency procedures at the launch pad Wednesday, NASA managers held an executive-level flight readiness review and cleared the ship for blastoff June 13 on a complex space station assembly mission.
NASA Launch Director Pete Nickolenko, directing his first shuttle launch campaign, said there is no contingency time left in the schedule to handle unexpected problems. But so far, the shuttle's systems are checking out normally and the team is optimistic about starting the countdown next Wednesday for a launch try one week from Saturday.
"We're running on all cylinders right now," Nickolenko said. "We're hitting our stride."
Over the past month, NASA launched the shuttle Atlantis on a successful mission to service the Hubble Space Telescope, the Russian space agency launched an additional three crew members to the International Space Station, Endeavour was moved from pad 39B to pad 39A for final processing, and Atlantis was returned to Florida from California where it landed May 24.
Endeavour's crew--commander Mark Polansky, pilot Douglas Hurley, flight engineer Julie Payette, David Wolf, Christopher Cassidy, Thomas Marshburn, and space station flight engineer Timothy Kopra--flew to Florida on Tuesday and reviewed emergency procedures at the pad Wednesday. All seven plan to strap in aboard the shuttle Thursday for a dress-rehearsal countdown.
Aboard the space station, meanwhile, commander Gennady Padalka and NASA flight engineer Michael Barratt plan to carry out two spacewalks, one Friday and the other next Wednesday, to rig the Zvezda command module for the eventual attachment of another docking port.
A few hours after the spacewalk ends, NASA will start Endeavour's countdown.
"It's been a really amazing schedule over the last couple of months," Polansky said Wednesday at the launch pad. "It's tight from the standpoint that we're here in Florida to climb in the vehicle tomorrow. We're going to go back home, take a day off, go into quarantine Saturday, come back down here Monday night and launch next Saturday. I mean, that's really tight.
"But I know from a training perspective, we're ready," he said. "It would be great if we could just climb in and go tomorrow, but I think our families would be a little upset because they're not here!"
The 16-day flight features five spacewalks to install an external experiment platform on the Japanese Kibo research module, to swap out batteries in the station's oldest set of solar arrays, and to deliver critical spare parts. Endeavour also will ferry Kopra to the lab complex for an extended stay and bring Japanese station flier Koichi Wakata back to Earth.
Endeavour was hauled to pad 39B in April to serve as a rescue vehicle for the crew of Atlantis. In the Hubble Space Telescope's orbit, the Atlantis astronauts could not seek safe haven aboard the space station if any major problem developed that might prevent a safe re-entry.
Engineers actually started a countdown for Endeavour late in Atlantis' mission to keep the rescue option open as long as possible. As it turned out, no such flight was needed and after bad weather blocked multiple attempts to bring Atlantis back to Florida, the ship was diverted to Edwards Air Force Base, Calif.
But the wisdom of processing Endeavour in parallel was made clear during a post-landing inspection of Atlantis. Space debris, a greater threat at Hubble's high altitude, apparently hit one of the shuttle's braking rocket nozzles, damaging the inner and outer surfaces.
The shuttle spent much of the mission flying tail first to shield more sensitive areas from debris impacts and small dings are not unusual. But Mike Moses, director of shuttle integration at the Kennedy Space Center, said this impact appeared to be on the high end of the scale.
As it now stands, NASA will have only three days to get Endeavour off the pad or the flight will be delayed until after the planned June 17 launch of NASA's Lunar Reconnaissance Orbiter. Going into the campaign, Nickolenko said the team would make two back-to-back attempts if necessary, but not three.
If the launch is delayed, and if the lunar orbiter takes off on time, NASA may be able to make additional attempts to launch Endeavour on June 19 and 20. After that, the flight would slip to July 11 because of temperature constraints related to the space station's orbit.