Much criticised by the official inquiry into the breakup of Columbia, which killed all seven astronauts on board, the National Aeronautics and Space Administration said it was determined to correct the mistakes as quickly as possible.

A 156-page document released by the US space agency said it wanted to send Atlantis to the International Space Station orbiting the Earth.

The plan mentions a launch window between March 11 and April 6 "for planning purposes only, that's our first available milestone. It's not we must, we are going to or we have to," said Doc Mireslon, a NASA spokesman in Washington.

Bill Readdy, NASA associate administrator for space flights, said "as we make progress towards the critical milestones (for a return to flight) and solve technical issues that will emerge, we will converge on a viable return to flight day, whether that turns out to be March, April, May, June or July, so be it.

"We will be safety driven and not schedule driven."

The flight resumption plans were released less than two weeks after the Columbia Accident Inquiry Board slammed NASA's management "culture" for contributing to the shuttle disaster on February 1.

The board listed 29 changes to safety and management that had to be carried out.

In its response, NASA said it will "pursue an in-depth assessment to identify and define areas where we can improve our culture and take aggressive corrective action."

Following revelations that engineers had warned about the loose piece of foam that fatally damaged Columbia's wing on take-off, NASA said the improvements would include changes in communications between managerial levels.

NASA shuttle chiefs said the engineers' warning had never reached them.

One of the technical priorities will be replacing the isolation foam around the external tank.

A piece of that foam broke off during the January 16 launch of Columbia and hit the underside of the left wing creating a breach "that allowed super-heated air to enter and destroy the wing structure during entry."

NASA will install electric heaters to prevent ice formation around the shuttle tanks.

It said cameras will be installed to monitor for damage during take-off and other surveillance equipment, including US spy satellites orbiting the Earth, will be used to watch for shuttle problems.

All launches will be carried out during daylight hours, NASA added, to improve safety monitoring. But this will reduce the number of "launch windows" for the shuttle.

Cameras will also be put on the International Space Station and its robot arm to inspect for damage to the shuttle.

The accident board also ordered that astronauts should be able to carry out space walks to carry out repairs when necessary. NASA said it is "developing materials and procedures for repairing Thermal Protection System tiles and reinforced carbon-carbon panels in flight."

The agency said it was not yet able to estimate the cost of all the extra work to be carried out but promised to lay out its "budgetary needs".

After the destruction of Columbia and the 1986 explosion of Challenger after takeoff, NASA has the Atlantis, Endeavour and Discovery shuttles left.

SPACE.WIRE