When the space shuttle takes to the skies again it will do so under new operating rules to be introduced following the Columbia tragedy.
Resumption of flights could take place in December.
New rules will restrict lift-off to daylight hours and limit the orbits the shuttle can reach. Astronauts will be trained in new spacewalks to inspect the shuttle.
The likely cause of Columbia's loss is a cracked heat-resistant tile. Consequently Nasa is sharpening its pre-flight shuttle safety inspections.
Much closer scrutiny
Nasa has set 18 December as a working date for a return to flight for its space shuttle fleet although many experts think that spring 2004 is a more likely date.
When it does fly again, the shuttle will only take-off during daylight, and then under a much closer scrutiny by cameras. Columbia accident investigators have commented on the poor quality of some views of Columbia's last launch.
It was 81 seconds after launch that Columbia's left wing was struck by a piece of foam that had come away from the external tank from the so-called bipod region where the shuttle is attached to the fuel tank.
That region of the external tank will be modified. The foam will be removed and replaced by small heaters that will prevent ice accumulation in the area.
Tests last week involving firing a piece of foam at a section of a space shuttle wing indicated that it could cause damage. Hairline cracks in the heat protective surface were seen. The cracks were barely visible on the surface but the damage was more extensive inside.
The Columbia Accident Investigation Board has said it draws no conclusions from the tests but experts have said that it may be that a crack that can only be seen from a few inches away may have let in superheated air that downed Columbia.
Inspection spacewalks
This is prompting Nasa to review its safety inspection procedures for space shuttles.
Nasa's chief, Sean O'Keefe, has also said that they will look at ways for spacewalking astronauts to go outside and examine the shuttle's wing in orbit. It may be that extra handholds are needed.
Veteran astronaut Story Musgrave has said that designing and training for such an inspection spacewalk would be relatively easy.
He says a spacewalker would be able to get their face within a few inches of the tiles to look for a crack but that actually repairing it in space would be another matter.
In the future, says O'Keefe, the shuttle will be routinely imaged by US spy satellites whilst in orbit to look for damage. In the past this only happened upon special request.
Another important change will be that space shuttles will, with one exception, only fly in orbits that allow docking with the International Space Station (ISS) so that astronauts can use it as a refuge in case of an emergency.
The one exception to this rule will be the 2004 Hubble Space Telescope servicing mission which is in an orbit from which the shuttle cannot reach the ISS.
The possibility of having a ground-based shuttle on standby for a quick launch during missions is also being considered even though it would be operationally very difficult to achieve.
The CAIB is due to release its final report on the accident next month.
^ Back to top | BBC Sport Home | BBC Homepage | Contact us | Help | ©