NASA has extended to September 2008 its six-year, $1.15 billion contract with Lockheed Martin Space Systems, New Orleans, to provide 35 Super Lightweight External Tanks for the Space Shuttle Program.
Under the modified contract, the 35 tanks will be produced at a rate of not less than six per year, against the eight per year agreed upon in the original contract issued in October 2000. The modification is said to add $341 million to the contract.
The contract includes the manufacture, assembly, test and delivery of the Super Lightweight Tanks and the operations and maintenance of NASA’s Michoud Assembly Facility in New Orleans.
This latest version of the tank, which flew for the first time in June 1998, is the same size as the tank it replaces, but is about 3,401.9 kilograms lighter.
The Super Lightweight Tank features major changes in materials and design. Its liquid hydrogen tank and the liquid oxygen tank are constructed of a new aluminium lithium, a lighter, stronger material than the metal alloy used to manufacture previous External Tanks.
The External Tank, which holds the liquid hydrogen fuel and liquid oxygen for the Shuttle’s three main engines, is the largest single component of the Space Shuttle and the only part of the Shuttle that is not reused.