NASA (Hall 3, A11) is preparing to transport Space Shuttle Discovery on its 4.2-mile (6.8km) trip back to pad 39B at Kennedy Space Centre for the "Return to Flight" launch in mid to late July.

The 122ft (37m) Discovery was returned from the launch pad to the centre's Vehicle Assembly Building last month. A new heater has been added to the pipeline on the external tank that carries liquid oxygen to the shuttle's main engines. This is a safety measure to minimise potential ice and frost build-up that could break away and damage the shuttle on launch.


The new ET-121 tank also has several other safety improvements, including an improved fitting that connects it to the orbiter. It has also been fitted with temperature sensors and accelerometers to gather information about the tank's performance during flight.

Technicians detached Discovery from its original external tank and mated it with the modified fuel tank last week. Other safety improvements include a boom that will allow astronauts to inspect the shuttle for any potential damage once in orbit.


The shuttle, complete with orbiter, external tank and solid rocket boosters, is now scheduled to start its trip back to the launch pad on Tuesday after storms were forecast today.


NASA makes no apologies for the delay. Administrator Michael Griffin says: "This is consistent with our overall approach to the STS-114 mission, which is that we're going to return to flight, we're not going to rush to flight. Our intent with this effort is to make certain we are as safe as we know how to be before we launch the Space Shuttle and its crew. We want it to be right.

"External tank modifications drove us to retarget for July. We've never been reluctant to adjust the dates as information becomes available."

The launch of Discovery on the STS-114 mission is scheduled for 13 July, with a window that extends to 31 July. During its 12-day mission, Discovery's crew of seven will test new hardware and techniques to improve shuttle safety and deliver supplies to the International Space Station.


Source: Flight Daily News