NEW ORLEANS ? The huge external fuel tank for NASA's final space shuttle mission was prepared for delivery to its Florida launch site Thursday, accompanied by a brass band and hundreds of handkerchief-waving workers celebrating its completion as the U.S. space agency winds down its 30-year shuttle program.
Lying on its side, the 154-foot (47-meter) fuel tank was rolled out of its processing center here at NASA's Michoud Assembly Facility to a waiting barge for the 900-mile (1,448-km) sea journey to the Kennedy Space Center in Florida.
"It's a bittersweet day for us, literally," said Mark Bryant, vice president of the External Tank Program for Lockheed Martin Space Systems. "It's tough to see this last production tank here, but boy do we have a lot of pride to get it here."
The shuttle fuel tank, designated External Tank-138 (ET-138), is slated to fly with the orbiter Endeavour?s STS-134 mission currently scheduled for no earlier than Feb. 26, 2011. It is set to be the 134th tank to be flown in the 37 years that NASA and its contractor Lockheed Martin have been developing, assembling and processing tanks at Michoud.
NASA's space shuttle fleet has been flying since April 1981 and is set to retire after two final shuttle missions. Before Endeavour's final flight, the shuttle Discovery is expected to launch on Nov. 1.
Final shuttle missions ahead
A packed crowd of Michoud workers and dignitaries gave the space shuttle fuel tank a rousing send-off.
The Storyville Stompers, a traditional area brass band, joined the employees as the tank rode atop a wheeled transporter on its 1 mile-trip to the dock and its waiting barge. Among the assembled crowd were space shuttle program manager John Shannon and astronaut Mark Kelly, who is slated to command the mission on which the tank will launch.
"I think most folks just think of the [external tank] as an empty fuel tank and it's really a lot more than that," Kelly said. "It's is a complicated piece of hardware and I'm amazed that it works so well every time."
NASA's rust-colored shuttle ?gas? tanks hold the 526,000 gallons (nearly 2 million liters) of super-cold liquid oxygen and liquid hydrogen propellant for the shuttle?s three main engines and serves as the ?backbone? for the spacecraft during launch. They are covered in foam insulation and plumbing lines to funnel propellant into a shuttle's engines. This last tank to fly was completed on June 25.
The external tanks have undergone several enhancements over the last three decades, first to lighten them to what NASA now calls its super-lightweight external tanks, and then to increase safety and reliance following the 2003 loss of space shuttle Columbia. The first shuttle fuel tanks were white, painted for insulation and heating protection, but NASA soon did away with the paint to save on added weight.
Columbia's heat shield was damaged during launch by a piece of falling fuel tank foam, leading to the loss of the shuttle and its crew during re-entry. Since then, NASA instituted new quality procedures for foam application, added cameras to the tanks to record any debris shed during liftoff, and inspects the tanks exhaustively before each flight. The goal is to make each tank better and safer than the last, NASA and Lockheed officials have said.
Joanne Maguire, executive vice president of Lockheed Martin Space Systems, called the new tank "the best fuel tank Lockheed has ever delivered to NASA."
Kelly and his space shuttle crew agreed.
"In our office, we have every confidence that every single tank is the best tank," Kelly said. "It's as good as it can be."
Endeavour's ET-138 fuel tank will be towed on a six-day trip from Louisiana to Florida by the MV Freedom Star, one of two NASA ships used to recover the shuttle?s twin reusable solid rocket boosters after every launch.
The journey is not expected to be hampered by the ongoing oil spill in the Gulf of Mexico.
For the previous shuttle fuel tank (ET-137), NASA needed to work with commercial ship operators to tow the tank?s Pegasus barge from Michoud to Gulfport, Mississippi, where the Freedom Star was waiting, unable to traverse a more shallow-water detour around the oil slick. For ET-138?s shipment, Freedom Star arrived at Michoud last Sunday.
One more fuel tank to go
Once at the Kennedy Space Center, the fuel tank will be moved into the Vehicle Assembly Building (VAB), where it will undergo final processing and await being mated with two shuttle solid rocket boosters and the orbiter Endeavour.
Here at Michoud, work is still being completed on one additional external fuel tank, ET-122, which was damaged by falling debris during Hurricane Katrina in August 2005. It is being restored to flight configuration and is scheduled for delivery to Kennedy in late September to serve as the ?Launch on Need? tank for shuttle Atlantis, should Endeavour?s STS-134 crew need emergency rescue during the mission.
NASA is also considering adding that contingency flight to its manifest ? extending the shuttle program by one mission ? to further support operations aboard the International Space Station.
If that flight is approved, then the current proposal would be to fly the repaired ET-122 tank with Endeavour on the STS-134 mission and have ET-138 still fly with the final space shuttle mission, NASA and Lockheed officials have said.
Should an extra shuttle flight be approved, NASA would likely launch the mission on a cargo delivery flight to the International Space Station in the summer of 2011, shuttle officials have said.
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Click here for more photos of the External Tank-138 rollout and delivery from collectSPACE.com.