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Atlantis roars into space to restart station assembly BY WILLIAM HARWOOD STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION Posted: September 9, 2006; Updated with notes from post-launch briefing The space shuttle Atlantis took off today on its fifth try, kicking off a long-awaited flight to restart assembly of the international space station three years after the Columbia disaster derailed construction.
"In my opinion, every one of these flights we're flying in the next 12 to 18 months ranks right up there as the most complicated flights we've every flown, including Hubble Space Telescope repair missions," said Paul Hill, mission operations manager at the Johnson Space Center. "The fact that we're going to go conduct a series of them for 18 months, each one of which is absolutely necessary for the next one to happen, without a doubt makes this the most complicated, most complex 18 months of manned spaceflight we have ever experienced. Said shuttle Program Manager Wayne Hale: "Clearly these are the most complicated spacewalk and assembly tasks that have ever been done before." Two weeks after being grounded by a launch pad lightning strike, tropical storm Ernesto, a fuel cell glitch and trouble with an external tank fuel sensor, Atlantis's main engines flashed to life on time, followed 6.6 seconds later by ignition of the shuttle's twin solid-fuel boosters at 11:14:55 a.m.
With a crackling burst of incandescent flame, Atlantis began accelerating skyward, hitting 120 mph in just 10 seconds and then rolling about its long axis to line up on a trajectory carrying it up the East Coast of the United States.
"Brent, it looks like you're long wait is over," Launch Director Mike Leinbach radioed the crew a few minutes before liftoff. "We wish you all the best luck in the world, Godspeed, and we'll see you back here in about two weeks." "We appreciate those words and the effort to make this launch window," Jett replied. "It's been almost four years, two return to flight missions, a tremendous amount of work by thousands of individuals to get the shuttle program back to where we are right now and that's on the verge of restarting the station assembly sequence. "We're confident over the next few weeks, and few years for that matter, that NASA's going to prove to our nation, to our partners and our friends around the world that it was worth the wait and the sacrifice. We're ready to get to work." Atlantis put on a spectacular Saturday skyshow as it climbed away from Florida's space coast atop a long cloud of churning exhaust, knifing through a partly cloudy sky. A camera mounted on the external fuel tank provided dramatic live views as the shuttle climbed toward space, showing the Florida coast line dropping away in the brackground as the ship arced out over the Atlantic Ocean. "What you saw today was a flawless count, a majestic launch and it was tough to get here," said NASA Administrator Mike Griffin. "This vehicle has not flown in many years and not everything in the count leading up to this day was easy. And in between we had to dodge tropical storms, lightning strikes and things like that. But we got here and it was just a flawless day." Atlantis made the climb to orbit using an external tank featuring so-called ice-frost ramps that are officially classified as "probable/catastrophic" in NASA's risk matrix, meaning there is a 50-50 chance of a catastrophic failure over the 100-flight life of a space shuttle. NASA is in the process of redesigning the ice-frost ramps but an interim fix will not be available until next year and the shuttle Discovery will make another flight with the old design in December. Reviewing launch video in slow motion, reporters could see several pieces of what appeared to be foam insulation separating from the external tank about four minutes after liftoff. But that was well above the denser atmospheric regions where debris poses a major threat to the shuttle's heat shield. In any case, there were no obvious signs of damage. "It's extremely preliminary but so far, we didn't see anything in the region of highest concern and the things that folks did see ... were well into the ascent phase where we really don't have debris concerns," said LeRoy Cain, chairman of the launch-site Mission Management Team. The video also showed the tank's externally mounted 17-inch-wide liquid oxygen feedline flexing a fair amount as the shuttle thundered away. A foam ramp that used to provide aerodynamic shielding was removed to eliminate a potential source of ascent debris. The oxygen line appeared to move more than one used during Discovery's launch in July, but Atlantis made a so-called high-Q ascent that subjected the shuttle to higher aerodynamic loads. Whether that played any role in the movement of the oxygen line it not yet known. But engineers will need several days to evaluate footage from a variety of cameras, data from wing leading edge sensors, a detailed inspection by the astronauts Sunday and additional inspections Monday during final approach to the station before Atlantis will be given a clean bill of health.
Joining Jett and Ferguson aboard Atlantis were flight engineer Dan Burbank, Joe Tanner, Canadian astronaut Steve MacLean and Heidemarie Stefanyshyn-Piper.
The solar alpha rotary joint, or SARJ, is the main component of what NASA calls the P3, or port 3, truss element. The solar arrays, their electronics and cooling radiators make up the P4 truss element. Both are bolted together and NASA refers to the combination as the P3/P4 truss.
Getting P3/P4 attached to the station's port truss will require one of the most ambitious flight plans ever put together for a shuttle mission.
Atlantis will dock with the space station Monday around 6:45 a.m. Just two hours later, Burbank, operating the shuttle's robot arm, will lift the P3/P4 truss out of the cargo bay and hand it off to MacLean, who will be operating the station's more massive Canadarm 2. Canadarm 2 will be mounted atop a mobile transporter on the far end of the port truss.
"Normally, once we finish the rendezvous, we open the hatches, everybody says hello and we get down to doing some (equipment and supply) transfers and a few things like that," said lead shuttle flight director Paul Dye. "We have so much on this mission that on this day, we're going to do the rendezvous and then we're going to ... take the payload, the P3/P4 truss segment, out of the bay and hand it off to the station before the crew goes to bed.
"So while we are equalizing air pressure between the spacecraft and opening the hatches and getting things connected and shaking hands and greeting, we're going to have crew on the aft flight deck getting ready to pull the P3 out."
Because the 50-foot-long orbiter boom sensor system, or OBSS, will be in place along the right side of Atlantis' payload bay, Burbank will have about one inch of clearance as he unberths P3/P4. To get past the OBSS, he will have to move the arm in a complex sequence, being careful not to bang into anything along the way.
"We'll grapple the payload, we'll move it up, back a little bit, up a little bit more to where we're clear, then out to the side and then we have a large automated maneuver which will put it into what we call the handoff position so the station can go and grab that with the big arm," Dye said.
"This is a pretty significant activity by itself and putting it on rendezvous day makes this a pretty long and very interesting day. Once we have it held in the handoff position, the station arm will move in and grapple. Once they've got it, we'll release it with our arm and at that point, it becomes (the station's) piece of equipment."
MacLean will leave P3/P4 parked overnight on the left side of the shuttle just below the station's unfinished truss. Before the crew goes to bed, they will change the orientation of the shuttle-station complex, rolling 45 degrees to port. That will aim the left side of the truss down toward Earth and help keep the stowed solar array blankets warm.
The next day, MacLean will move P3/P4 up to the station's P1 truss (there is no P2 element). Once properly aligned, motorized bolts in P1 will be powered up to lock the new truss in place.
As soon as three of the four attachment bolts are engaged, Tanner and Piper will exit the station's Quest airlock and begin a complex spacewalk to make critical electrical connections required to power heaters and other systems necessary to keep the new arrays alive.
Electrical power to the U.S. section of the space station currently is provided by solar arrays mounted atop a short truss, known as Z1, that extends up in the zenith direction from the station's multi-hatch Unity module.
Those arrays, known as P6, will be moved down to the main solar array truss next year and attached to a short spacer, known as P5, that will be bolted to P4 during the next shuttle assembly mission in December.
To wire in the new P4 arrays, flight controllers in Houston will carefully power down the station's two P6 electrical channels, one at a time, so Tanner can hook up 13 umbilical cables between P1 and P3/P4.
"There are about a hundred pages of ground commanding that have to go on in order to get things powered down in the right order and get things switched over and powered back up again afterwards," station flight director John McCullough said in an interview. "It's one of the more tightly choreographed EVAs that we've done as far as ground and crew interaction."
The P4 solar arrays are packed up like venetian blinds in four large "blanket boxes." Tanner and Piper will prepare those boxes for deployment and start the process of readying the SARJ for operation.
NASA managers may insert an extension day after the first spacewalk to give the astronauts time to carry out additional heat shield inspections if any "areas of interest" are identified during the inspections Thursday or during final approach to the station.
But as it now stands, MacLean and Burbank will carry out a second spacewalk the day after the first to complete preparations for SARJ operation and solar array deploy. That night, flight controllers will send commands to extend the arrays one mast bay in a confidence test before the astronauts take over the next morning. First, they will extend each array to 49 percent and then, after letting the sun heat them up a bit, the rest of the way.
The stepwise approach is being taken because of problems encountered in December 2000 when the P6 array was deployed. When the first P6 wing unfurled, several solar cell panels stuck together, resulting in a jerky motion that caused a tension cable to unwind and jump from its spool.
The second P6 array was deployed in high-tension mode, which prevented additional problems. Engineers now believe the "stiction" was caused by subtle effects of atomic oxygen coating the arrays and low temperatures. For the P3/P4 deploy, the arrays will be extended in high-tension mode with enough solar heating to preclude similar problems.
Fully extended, the 38-foot-wide arrays will span 240 feet from tip to tip. Some 66,000 solar array cells will generate nearly 66 kilowatts of usable power. A dozen massive batteries will provide power when the station moves into Earth's shadow and ammonia lines inside accordion-like radiator panels extending 44 feet will shed the heat generated by the electrical circuits.
But the new arrays will not provide power to the station until the next shuttle mission in December when the left side of the P6 array is retracted. In its current position, the port wing of the P6 array is at right angles to the P4 wings, extending into the area where P4 eventually will rotate.
With the new arrays deployed, Tanner and Piper will stage a third spacewalk the following day to complete SARJ activation, to carry out critical repairs on the station's S-band antenna system and to install a thermal blanket around components of the lab's high-speed KU-band antenna.
If all goes well, Atlantis will undock from the space station Sept. 17 - Sept. 18 if the flight is extended a day. The next day, the crew will carry out heat shield inspections to make sure Atlantis hasn't been hit by any orbital debris or micrometeoroids since they carried out a post-launch inspection on the second day of the mission.
Landing back at the Kennedy Space Center is targeted for a few minutes before 6 a.m. on Sept. 20, Sept. 21 if the flight is extended. Assuming the shuttle's external tank performed well and no major impact damage occurs, NASA managers will relax a post-Columbia requirement to launch in daylight, opening up more space station launch windows and clearing the way for a night launch of Discovery Dec. 14.
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STS-115 patch The official crew patch for the STS-115 mission of space shuttle Atlantis to resume orbital construction of the International Space Station. Choose your store:U.S. - U.K. - E.U. - Worldwide  |
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