July 8, 2010
(New Orleans) — The external tank that will fly on NASA's final space shuttle mission was rolled out for delivery to its Florida launch site on Thursday. A brass band and hundreds of handkerchief-waving workers trailed the tank as it was driven to a waiting barge, celebrating in New Orleans-style the completion of their work.
Lying on its side, the 154-foot tank left the final test and checkout building here at the Michoud Assembly Facility to begin the 900-mile 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, speaking a ceremony held prior to the roll out getting underway. "It's tough to see this last production tank here, but boy do we have a lot of pride to get it here."
Photo Gallery: Final shuttle fuel tank to fly rolls out
The shuttle tank, designated External Tank-138 (ET-138), is slated to fly with orbiter Endeavour's STS-134 mission currently scheduled for no earlier than
Feb. 26, 2011. It is set to be the 134th tank to fly in the 37 years that NASA and its contractor Lockheed Martin have been developing, assembling and processing tanks at Michoud.
NASA's shuttle fleet has been flying since April 1981 and is set to retire after just 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 New Orleans-area brass band, plays as the external tank rolls out. (collectSPACE)|
The Storyville Stompers, a traditional area brass band, joined the employees as the tank rode atop a wheeled transporter on its one mile-trip to the dock and its waiting barge. Among the assembled crowd were shuttle program manager John Shannon and astronaut Mark Kelly, who is slated to command the mission that 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 is a complicated piece of hardware and I am 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 the shuttle's three main engines. This last tank to fly was completed on June 25.
The tanks have undergone numerous 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 the space shuttle Columbia. The first two external tanks were white, painted for insulation and heating protection, but the coating was soon did away with 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 on their re-entry into the atmosphere. Since then, NASA instituted new quality procedures for foam application, added cameras to the tanks to record if any debris is 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 remarked. "It's as good as it can be."
Endeavour's ET-138 tank will be towed on a six-day trip from Louisiana to Florida, first by two tugs and then by the MV Freedom Star, one of the two ships used to recover the shuttle's two reusable solid rocket boosters after every launch.
As with earlier shuttle fuel tanks over the past few years, NASA employs tugs to tow the tanks' Pegasus barge from Michoud to Gulfport, Mississippi, where the Freedom Star waits, unable to traverse through the shallow waters of the Intracoastal Waterway. For ET-138's shipment, Freedom Star arrived at Gulfport last Sunday.
The tank's journey is not expected to be hampered by the ongoing oil spill in the Gulf of Mexico.
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 solid rocket boosters and the orbiter Endeavour.
Here at Michoud, work is still underway 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 be flight-worthy and is scheduled for delivery to Kennedy in late September to serve as the "Launch on Need" tank for orbiter Atlantis, should the crew aboard Endeavour need emergency rescue during their mission.
|A technician works on External Tank-122 (ET-122), which was damaged during Hurricane Katrina in 2005. (collectSPACE)|
NASA is also considering adding that contingency flight to its manifest -- extending the shuttle program -- 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 added, NASA would likely launch the mission on a resupply delivery mission to the International Space Station in the summer of 2011, shuttle officials have said.