Spaceflight Now STS-102

Discovery thunders into orbit
Mission to swap station crews
BY WILLIAM HARWOOD
SPACEFLIGHT NOW

Posted: March 8, 2001
Updated: 07:00 a.m. EST

  Discovery
Space shuttle Discovery lifts off at dawn. Photo: Steven Young/Spaceflight Now
 
By dawn's early light, the shuttle Discovery rocketed into orbit today and set off after the international space station to deliver the lab's second full-time crew and nearly five tons of supplies and equipment.

With its three three hydrogen-fueled main engines firing at full throttle, Discovery's two solid-fuel boosters ignited with a ground-shaking roar at 6:42:09 a.m. - two minutes after sunrise - instantly pushing the 4.5-million-pound spacecraft away from pad 39B.

The shuttle cleared the top of the launch pad gantry in under 10 seconds, rolled about its vertical axis to put the crew in a heads-down orientation beneath the external tank and thundered away on a trajectory paralleling the East Coast.

"Roll program, Houston," commander James Wetherbee radioed as the shuttle climbed skyward.

"Roger roll, Discovery," called astronaut Gus Loria from mission control.

With a cloudless, crystal clear sky, Discovery's on-time launch was visible for miles around, a spectacular sky show for area residents and tourists gathered along nearby roads and beaches.

The exhaust from the ship's boosters appeared reddish brown close to the pad and then changed to brilliant white as the vehicle climbed higher into the light of the rising sun.

Discovery's countdown was timed to hit zero at the moment Earth's rotation carried the launch pad into the plane of the space station's orbit. At liftoff, the station was about 1,000 miles south of Perth, Australia, some 11,300 miles from the Kennedy Space Center.

Flight controllers at the Johnson Space Center in Houston planned to uplink video of Discovery's launching through the station's video conferencing system.

In addition, station commander William Shepherd, Sergei Krikalev and Yuri Gidzenko were told to look for Discovery's exhaust plume when they passed northwest of the Florida spaceport around 7:25 a.m.

By launching directly into that orbital plane, Discovery's crew was able to minimize the propellant necessary to reach its target orbit while improving the odds of reaching the outpost even if a main engine fails to perform at full power.

But the ascent appeared flawless and eight-and-a-half minutes after liftoff, Discovery slipped into space.

Wetherbee and his crewmates - pilot James Kelly, Andrew Thomas, Paul Richards and the station's second full-time crew, Russian commander Yury Usachev, James Voss and Susan Helms - then began doffing their pressure suits and stowing no longer needed seats.

The primary goal of the 103rd shuttle flight is to exchange station crews. Shepherd and company will return to Earth aboard Discovery on March 20 after 140 days in space, leaving Usachev and his two crewmates behind aboard the station.

The actual crew transfer will take place in stages, however, with Usachev officially taking Gidzenko's place aboard the station shortly after the shuttle docks early Saturday.

Voss will take Krikalev's place early next week, after a spacewalk overnight Saturday by Voss and Helms. Finally, Helms will move aboard the station late next week, formally taking Shepherd's place.

Crew transfers become official with installation of a custom Soyuz seat liner fitted to support the new flier in case of an emergency that might require a return to Earth in the Russian spacecraft.

  Expedition Two
Expedition Two crew patch. Photo: NASA
 
The staggered transfer process is required to give Shepherd time to fully brief his replacement on station operations and to allow Voss and Helms to complete their shuttle assignments.

"Yury Usachev and Yuri Gidzenko both fly the center seat of the Soyuz, so it's very logical that they change at the same time so that the seat allocations in the Soyuz are preserved," Thomas said in a NASA interview.

"But the main thing, of course, is that Yury Usachev will be the commander and he needs to work directly with the Expedition 1 commander, Bill Shepherd, on what we call handover.

"It's very important that he get a lot of time, one-on-one, with Bill Shepherd," Thomas continued. "That's why he's exchanging first, and Yuri Gidzenko will come to the shuttle and then Yury Usachev can spend this very important time doing handover operations with Bill Shepherd."

Usachev will be the station's first Russian commander. But Voss and Helms both speak fluent Russian, Usachev speaks English and all three seem to enjoy working together.

"We do defer to Yuri as the commander among the group as the person who has the ultimate decision among us if we have a disagreement about anything having to do with the mission," Helms said at a news conference.

"Both Jim and I absolutely trust Yuri to make that final decision as our commander. So right off the bat, I think we have got a good rapport among us."

Said Voss: "I consider myself blessed to have two people who I get along with very well to be crewmates for a long stay in space."

If all goes well, Wetherbee will guide Discovery to a docking with the space station around 12:36 a.m. Saturday after a two-day orbital chase.

Unlike recent dockings in which shuttle crews approached from directly above or below the station, Wetherbee will approach from a point directly in front of the outpost with Discovery's tail pointing toward Earth and its belly facing in the direction of travel.

Dockings from above and below can take advantage of Earth's gravity and orbital mechanics to provide a natural braking force, which allows shuttle pilots to minimize the use of upward-firing thrusters that might damage the station's solar arrays or optical sensors.

  Docking
Illustration of Discovery's approach to the space station during docking. Photo: Spaceflight Now/NASA TV
 
But Discovery must dock at a port on the forward end of the Destiny laboratory module.

"Unfortunately, as the space station gets bigger and bigger, it does not have the capability, or we desire not to maneuver it such that we can approach from below," Wetherbee said.

"We'd like to leave it in the current (orientation so) it'll always be flying in parallel to the surface of the Earth. We have to approach from in front of the space station, and we don't have the natural braking capability due to orbital mechanics.

"And so we have to be very careful as we're approaching," he said. "We don't want to plume the station with our braking jets. ... This is the way we'll do it into the future, because, again, as it gets bigger and bigger, you really don't want to maneuver it very much."

The station currently is made up of four pressurized modules connected end to end. NASA's Destiny laboratory module, attached last month, is bolted to the multi-hatch Unity node. Unity, in turn, is connected to the Russian-built NASA-financed Zarya module, which is attached to the Russian Zvezda command module.

The Soyuz ferry craft that carried Shepherd, Gidzenko and Krikalev into orbit is bolted to Zarya's Earth-facing, or nadir port. An unmanned Progress supply ship is docked to Zvezda's aft port while a shuttle docking port called PMA-2 is attached to Destiny's forward port at the far end of the station.

Unity's two side hatches current are vacant, but its upward-facing port is occupied by a boxy structural truss that houses the station's four stabilizing gyroscopes.

Bolted to the top of the Z1 is the P6 solar array, which provides most of the station's electrical power. The two panels making up the P6 array stretch 240 feet from tip to tip, oriented like two huge wings extending to either side of the station's central axis.

  ISS
With its new Destiny laboratory contrasted over a blue and white Earth, the international space station was photographed by one of the shuttle Atlantis astronauts following undocking last month. Photo: NASA
 
Discovery's primary payload is the Italian-built Leonardo pressurized logistics module, a dedicated space station cargo carrier that will be used periodically to carry supplies and equipment to the complex.

Leonardo is designed to be attached to the station like any other pressurized module and if all goes well, Thomas, operating the shuttle's robot arm, will dock the cargo carrier to Unity's downward facing port early Monday.

The station crew then will open hatches between the cargo carrier and the station and begin moving some 9,600 pounds of equipment and supplies on board.

But Unity's downward-facing port currently is occupied by a shuttle docking adapter called PMA-3. Before Leonardo can be attached, PMA-3 must be removed and re-mounted on Unity's unoccupied port, or left-side, hatch.

That work will occur during the first of two spacewalks planned for Discovery's mission. Voss and Helms are scheduled to begin the planned seven-hour excursion just before midnight Saturday.

The first items on the agenda are to disconnect electrical cables between Unity and PMA-3. The spacewalkers then will attach a cradle to Destiny's hull that will be used later to anchor the station's robot arm, scheduled for installation in April.

Helms and Voss also will mount a so-called rigid umbilical to Destiny that will route video and data from the Canadian-built robot arm after it is installed next month.

A major objective of the Expedition 2 crew's stay aboard the station is to check out and activate the complex robot arm before arrival of the station's main airlock in June. The robot arm is required to install the airlock.

After cleaning up the cargo bay, Voss and Helms will return to Discovery's airlock and hook their spacesuits up to shuttle air and power. Then they will stand by while Thomas, operating the shuttle's robot arm, removes PMA-3 and reposition's it on the port side of the Unity module.

If any problems develop, Voss and Helms can resume their spacewalk to help out as necessary. Assuming no problems develop, they will start repressurizing the airlock around 7 a.m. to wrap up the 101st U.S. spacewalk.

  MPLM
Illustration of Leonardo being attached to Unity. Photo: Spaceflight Now/NASA TV
 
The next day, Thomas will use the robot arm to mount Leonardo on Unity's nadir port and the crew will begin work to transfer nearly five tons of equipment and supplies to the space station.

"Within Leonardo, we're carrying the robotics work station for the international space station," Thomas said. "This is the system of video monitors, computers and hand controls that will enable operators to actually run the space station robotic arm when it comes up (in April), so it's a very important piece of equipment.

"They'll be transferring a DC-to-DC Converter Unit that's in one of the racks that will be providing power for the lab module. Obviously, that's a very important thing to have. There [are] a lot of tools, logistics, water transfer equipment.

"There's a cycle ergometer exercise system that has to go across and things like that," Thomas said. "So, they're going to be very busy getting all of that equipment across. And some of it needs to be done fairly promptly."

And Leonardo also carries the Human Research Facility rack, a suit of life science experiments that represents the space station's first research equipment.

Shortly after 7 a.m. on Monday, the station crew will open the hatches leading into Leonardo to begin equipment transfers.

Later that night, Thomas and Richards will begin the mission's second spacewalk to connect power lines to an equipment storage rack on the station's hull. The excursion is expected to last just four hours or so. Helms will assist with the spacewalk by acting as the overall coordinator, helping Thomas and Richards stay on their timeline. Once the spacewalk is complete, Helms will take Shepherd's place aboard the station, completing the crew transfer process.

Expedition Two
The official portrait of the Expedition Two crew. Photo: NASA
 
The space station currently is equipped with just two staterooms, both in the Russian Zvezda command module. Voss and Usachev will use those sleep stations while Helms will bunk in the U.S. laboratory module, Destiny.

Voss said he plans to rig up a privacy curtain for Helms in a vacant experiment bay in the lab module, setting up an impromptu stateroom in the scientific heart of the complex.

"Susan Helms will (change) positions with Bill Shepherd, who will have, by then, completed his handover as commander, and he will come on board the shuttle, completing the entire crew transfer," Thomas said.

"Of course, there's still a lot of work to be done. There's still equipment on board that needs to be transferred between the two vehicles mostly from the MPLM. There's still a lot of discussion between the two Expedition crews about day-to-day operations - what we call handover - to make sure that the new crew persons understand where everything is and what the day-to-day operational procedures require and things like that."

Thomas spent more than four months aboard the Russian Mir space station. And in a news conference before launch, he offered some advice to Usachev, Voss and Helms:

"You've got to avoid what I call the 'Groundhog Day' syndrome," he said. "Just like in that movie, 'Ground Hog Day,' where every day looks just like every other day and they all roll one into another and each day's identical and the novelty of the days wears off, suddenly you lose interest. You've got to find ways to avoid the Groundhog Day syndrome. "If you remember that movie, the lead character did that by using his time creatively, doing things that interested him. In a sense, that's a good metaphor for the way you do a station flight. You use that time, that unique opportunity you have, to find ways of getting your recreational needs and your personal needs met."

For recreation, station crews can watch DVD movies, chat with friends and family members using a teleconferencing system, send and receive email, exercise and, of course, look out the window at the Earth passing by 240 miles below.

"I'm taking books . . . some personal books, some I've read before, some new ones that I haven't read to enjoy reading in space, a small bible," Voss said. "I'm also taking a bunch of photographs of my family, friends, my dog, my airplane - things that I know that I'll miss that I'd like to see once in a while."

Helms said she plans to finall read "War and Peace" during her stay aboard the station.

If all goes well, the equipment transfer work will be complete by the night of March 16.

  MPLM
Animation shows Leonardo being returned to Discovery's payload bay for the ride back to Earth. Photo: Spaceflight Now/NASA TV
 
The next morning, the shuttle crew will detach Leonardo, now loaded with 2,630 pounds of trash and equipment no longer needed aboard the station, and re-berth it in Discovery's cargo bay for return to Earth,

With Leonardo safely tucked away, the Discovery is scheduled to undock from the station at 10:57 p.m. the night of March 17. As usual with shuttle-station undockings, Discovery's pilot - James Kelly - will be at the controls for a photo-documentation fly around.

"We're planning on doing basically a full loop all the way around the station, back up to the top, and then we're going to separate from there," Kelly said in a NASA interview.

"The major reason we do the fly-around is basically to do an exterior survey of the station. The station's going to change throughout its years, either from micrometeoroid debris hits or wear and tear or as EVAs happen. They're changing the outside of the station constantly. They're putting new gear on, moving things around, stuff like that. There's going to be some deterioration, things like that.

"So we want to get a good photographic record of all these things. We do the fly-around to basically take a photo survey of the outside of the station and see if anything has changed, and we take as many pictures as we can with different types of cameras."

Discovery is scheduled to return to Earth around 2 a.m. on March 20.


Now showing
Our Mission Theater subscribers can enjoy the following video clips. Non-subscribers can sign-up now for full access to this special coverage.
Learn about the payloads riding riding aboard space shuttle Discovery and what each will do in this narrated NASA animation.
  PLAY (476k, 1min10sec QuickTime file)

NASA animation shows Discovery's approach and docking to the international space station, which will occur in a different fashion on this mission. This occurs on Flight Day 3.
  PLAY (194k, 28sec QuickTime file)

A detailed preview of the work to be performed during the mission's first spacewalk by Jim Voss and Susan Helms on Flight Day 4.
  PLAY (1.0M, 1min56sec QuickTime file)

The Italian-built "Leonardo" logistics module to hoisted out of Discovery's payload bay and attached to the Unity node of the space station using the shuttle's robotic arm on Flight Day 5.
  PLAY (141k, 24sec QuickTime file)

Watch a preview of the mission's second spacewalk to be performed by Andy Thomas and Paul Richards. It will occur on Flight Day 6.
  PLAY (343k, 42sec QuickTime file)


Status Summary

See the Status Center for full play-by-play coverage.