STS-134 countdown begins; astronauts arrive for launch

By WILLIAM HARWOOD
CBS News

KENNEDY SPACE CENTER, FL--The shuttle Endeavour's crew flew to Florida Tuesday for the start of their countdown to blastoff Friday on a long-awaited mission to deliver supplies, spare parts and a $2 billion cosmic ray detector to the International Space Station. Forecasters are predicting an 80 percent chance of good weather.

The shuttle Endeavour's crew flew to the Kennedy Space Center Tuesday to prepare for launch Friday. From left to right: Gregory Chamitoff, Andrew Feustel, commander Mark Kelly, pilot Gregory Johnson, Michael Fincke and Roberto Vittori.
Arriving in sleek T-38 jet trainers, commander Mark Kelly and his five crewmates -- pilot Gregory H. Johnson, Michael Fincke, Gregory Chamitoff, Andrew Feustel and European Space Agency astronaut Roberto Vittori -- landed at the shuttle runway just before 1 p.m. EDT (GMT-4) after a flight from Houston.

One hour later, at 2 p.m., engineers in the nearby launch control center started Endeavour's countdown, setting the stage for launch of NASA's next-to-last shuttle mission at 3:47:52 p.m. Friday. It will be Endeavour's 25th and final mission since its maiden voyage in May 1992.

"We're really happy to be here today," Kelly told reporters at the shuttle runway. "We got a chance to take a look at the orbiter as flew over. ... It's great to see Endeavour all ready to go again. Endeavour has had a pretty amazing career. It's been flying now for 18 years. This is going to be Endeavour's 25th flight and me and my crew are excited to be a part of it."

Kelly's wife, Arizona Rep. Gabrielle Giffords, plans to arrive later this week to watch Endeavour's launching. Giffords, shot in the head Jan. 8 in Tucson, has been recovering in Houston and this will be her first major trip away from the hospital.

"I'm personally looking forward to my wife, Congresswoman Gabrielle Giffords, getting here pretty soon, to be here in time for our launch on Friday," Kelly said. "It's something she's been looking forward to for a long time. She's been working really hard to make sure that her doctors would permit her to come, and she's more than medically ready to be here. She's excited about making this trip."

Kelly thanked the thousands of engineers and technicians who worked on Endeavour over the years, joking that "we're going to take Endeavour out for a couple of more, probably five or six million more miles."

"After 25 flights, we will hopefully land here on this runway and then Endeavour is done with its service to the country," he said. "Over the years, Endeavour's had thousands and thousands of very dedicated KSC government an contractor employees working on it. We want to thank every one of them for the hard work that they've done to get this vehicle ready time and time again. ... My crew and I are really excited to be a part of that. We're looking forward to launching on Friday."

NASA Test Director Jeremy Graeber said engineers were not tracking any significant issues going into the countdown and shuttle weather officer Kathy Winters said forecasters are predicting generally good weather through the weekend. The only concern is possibly high crosswinds from a front expected to move through the area Thursday night.

She said the models indicate an 80 percent chance of acceptable weather Friday, dropping to 70 percent on Saturday and moving back up to 80 percent "go" on Sunday.

"Overall, our main concern for launch day is going to be crosswinds," she said. "There's just a 20 percent chance of KSC weather prohibiting launch. The main thing is we just want to get that frontal system through us on Thursday evening and still be able to complete all our pre-launch operations."

Engineers plan to pump liquid oxygen and hydrogen aboard the orbiter starting at 11:30 a.m. Wednesday to power the shuttle's electricity producing fuel cells, a procedure that should be complete by around 6 p.m. After an eight-hour hold, main engine preparations will get underway along with checkout of various avionics systems.

A 13-hour 20-minute hold will begin at 10 a.m. Thursday, during which communications links will be activated and checked out. A protective gantry will be pulled away from the shuttle starting around 7 p.m. Thursday, exposing the orbiter to view.

If all goes well, engineers will begin pumping a half-million gallons of supercold liquid oxygen and hydrogen rocket fuel into Endeavour's external tank around 6:22 a.m. Friday. Kelly and his crewmates plan to don their pressure suits and head to the pad to begin strapping in a few minutes before noon.

As with most space station flights, Endeavour's launch is timed for the middle of a 10-minute window, roughly the moment Earth's rotation carries pad 39A into the plane of the space station's orbit. A detailed countdown timeline is posted on the Fight Data File page, along with an updated launch windows chart and other useful data. The STS-134 flight plan and the mission television schedule are posted separately.