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Space Shuttle Columbia disaster occurred on February 1, 2003, when the Space Shuttle Columbia disintegrated over Texas during re-entry into the Earth's atmosphere, with the loss of all seven crew, shortly before it was scheduled to conclude its 28th mission, STS-107.

Mission STS-107 was the 113th Space Shuttle launch. It had been delayed 18 times over the two years from its original launch date of 11 January 2001 to its actual launch date of 16 January 2003. A well-publicized launch delay due to cracks in the shuttle's propellant distribution system occurred one month before a 19 July 2002 launch date, but the Columbia Accident Investigation Board (CAIB) determined that this delay had nothing to do with the catastrophic failure six months later.

The loss of the Columbia was caused by damage sustained during launch when a piece of flab insulation the size of a small briefcase and known as the Right Bipod Foam Ramp broke off the Space Shuttle external tank (the main propellant tank) under the aerodynamic forces of launch. The debris struck the leading edge of the right wing on the number 7 reinforced carbon-carbon (RCC) tile, damaging the Shuttle's thermal protection system (TPS). While Columbia was still in orbit, some engineers suspected damage, but NASA managers limited the investigation on the grounds that little could be done even if problems were found.

NASA's Shuttle safety regulations stated that external tank foam shedding and subsequent debris strikes upon the Shuttle itself were safety issues that needed to be resolved before a launch was cleared, but launches were often given the go-ahead as engineers unsuccessfully studied the foam shedding problem. The majority of Shuttle launches recorded such foam strikes and thermal tile scarring in violation of safety regulations. During re-entry of STS-107, the damaged area allowed the hot gases to penetrate and destroy the internal wing structure, eventually causing the in-flight breakup of the vehicle.

RESCUE:

Normally a rescue mission is not possible,     due to the time required to prepare a shuttle for  launch, and the limited consumables (power, water, air) of an orbiting shuttle. However, Atlantis was well along in processing for a March 1 launch, and Columbia carried an unusually large quantity of consumables due to an Extended Duration Orbiter (EDO) package. The CAIB determined that this would have allowed Columbia to stay in orbit until flight day  30 (February 15). NASA investigators determined that  Atlantis processing could have been expedited with no  skipped safety checks for a February 10 launch. Hence  if nothing went wrong there was a five day overlap for   a possible rescue.

 REPAIR:

NASA investigators determined on-orbit repair by the shuttle astronauts was possible but risky, primarily due to the uncertain resiliency of the repair using available materials.

Columbia did not carry the Canadarm, or Remote Manipulator System, which would normally be used for camera inspection or transporting a spacewalking astronaut to the wing. Therefore an unusual emergency EVA would have been required. While there was no astronaut EVA training for maneuvering to the wing, astronauts are always prepared for a similarly difficult emergency EVA – to close the external tank umbilical doors located on the orbiter underside. During launch these doors are open for the propellant feed lines from the external tank to supply the main engines in the orbiter tail. If they fail to close after jettisoning the external tank, it constitutes a thermal protection breach which would destroy the orbiter upon re-entry. This requires an emergency EVA to close them manually. Similar methods could have reached the shuttle left wing for inspection or repair.

For the repair, the CAIB determined the astronauts would have to use tools and small pieces of titanium, or other metal, scavenged from the crew cabin. These heavy metals would help protect the wing structure and would be held in place during re-entry by a water-filled bag that had turned into ice in the cold of space. The ice and metal would help restore wing leading edge geometry, preventing a turbulent airflow over the wing and therefore keeping heating and burn-through levels low enough for the crew to survive re-entry and bail out before landing. Because the NASA team could not verify that the repairs would survive even a modified re-entry, the rescue option had a considerably higher chance of bringing Columbia's crew back alive.

LESSONS FOR INDIAN SPACE PROGRAM 

• While lift off it must be ensured that no kind of wires are attached to the spacecraft.
• The design of the spacecraft should be such that it can open up to have wings or fold up to look like a rocket.
• There should be cameras to give a total view of the craft.
• The heat shield of the spacecraft should be a single block or can consist of multiple blocks covering large areas.
• The cabin of the crew should be like a capsule in itself and should be designed to take the impact of a collision with ground and stay afloat in water.
• While entering the Earth’s atmosphere the craft can launch all its water packed in plastic in the forward direction in order to slow down it’s speed.