Plunging back to earth after a 16 day mission ,the space shuttle "columbia" streaked through the darkness at almost 8km/s,fast enough to fly from Delhi to Mumbai in 2 min !The crew included commander -->Rick Husband,trainee co-pilot -->William mccool,flight engineer -->Kalpana Chawla,mission specialists--> Laurel Clark and Dave Brown,payload commander -->Michael Anderson,pilot colonel -->Ilan Ramon. A joyful mood had settled in , brought on by the knowledge that a triumphant homecoming was just minutes away.It was 8:44 am on feb 1,2003.In mission control at the Johnson space center in Houston,a huge projection television screen at the front of the room showed columbia's location on a map that traced the spacecraft's predicted path to Florida.The shuttle was right on course.As columbia streaked towards the California- Nevada border some 4000 km away ,mechanical systems officer Jeff Kling suddenly noticed something unusual in the flow of data from the shuttle appearing on his computer screen.Downward pointing arrows appeared beside readings from sensors measuring hydraulic fluid temperatures in the shuttle's left wing.Something was not right.
Kling's thoughts immediately flashed back to columbia's launch on jan16,2003,16 days earlier.He recalled a briefcase sized piece of foam insulation that broke away from the shuttle's 15 storey external fuel tank almost 82 seconds after liftoff and slammed into the left wing .An unsettling thought crossed Kling's mind,"Was the loss of the left wing temperature sensors related to the insulation hit?" . "It couldn't be " he thought.Damage to the shuttle from flying debris was something that has concerned NASA for years.But shuttle managers after trying various unsuccessful measures to prevent the foam shedding ,has deemed the situation"an accepted risk".Now that problem had come roaring back.
In just 3 min the shuttle would be moving out of maximum heat buildup.There was reason to hope that all was well.Suddenly Rick called down his first query since columbia had entered earth 's atmosphere15 min earlier"and ,uh,hou..."he began. Transmission was cut off. A few seconds later kling saw more down arrows on the screen,this time signalling loss of tyre pressure.The ground flight controller Charles hobaugh radioed Rick,Rick made another attempt to contact mission control,replying to hobaugh with,"roger,uh,buh...".Again the transmission was cut off,along with it the flow of data from the shuttle. It was now some 30 seconds after 8:59am.Back at Johnson ,hobaugh radioed Rick :"columbia ,houston,commcheck.".There was no reply.NASA had lost columbia.
ANSWERS AT LAST:On march 19 a firefighter from Florida was walking a search line over hilly terrain near hemphill. He saw a square metal box painted black.It was columbia's Modular Auxillary DataSystem(MADS) Recorder .It had survived columbia's disintegration. The 28 track tape from the doomed spacecraft gave investigators the data they needed to determine that a breach had occurred in the leading edge of the left wing ,where some people believed the foam has struck. Still,doubts remained about whether a small piece of light weight material could have done such damage.
To resolve the issue,NASA conducted tests,using powerful nitrogen gas-powered cannon used to fire rubber projectiles at various aircraft components to test their resistance to bird strikes and similar unexpected collisions.On july 7 a block of foam weighing 760 gm-appprox size of chunk that hit columbia-was fired at a panel at 850kmph,the speed at which engineers had calculated it had probably hit.To the crowd of reports and NASA officials looking from a safe distance ,the foam's path was too swift to see,but the results were instantly obvious.A ragged 41-cm wide hole appeared on the lower side of the panel. The crowd gasped. The most complicated machine ever built got knocked out of the sky by 760 gm of foam.NASA was blamed for having a "broken safety culture".Frank buzzard director of the task force that operated as an liaison between the CAIB and NASA ,summed up the feelings of many when he said,"I am not sure we would have committed that next shuttle.Two of the last three had had foam come off(at launch).But the fact that we didn't try made us feel we let them down".
On jan 6,2004 NASA administrator Sean o'keefe announced that the rover spirit's landing site on mars would be named columbia memorial station,in memory of the seven lost astronauts
Kling's thoughts immediately flashed back to columbia's launch on jan16,2003,16 days earlier.He recalled a briefcase sized piece of foam insulation that broke away from the shuttle's 15 storey external fuel tank almost 82 seconds after liftoff and slammed into the left wing .An unsettling thought crossed Kling's mind,"Was the loss of the left wing temperature sensors related to the insulation hit?" . "It couldn't be " he thought.Damage to the shuttle from flying debris was something that has concerned NASA for years.But shuttle managers after trying various unsuccessful measures to prevent the foam shedding ,has deemed the situation"an accepted risk".Now that problem had come roaring back.
In just 3 min the shuttle would be moving out of maximum heat buildup.There was reason to hope that all was well.Suddenly Rick called down his first query since columbia had entered earth 's atmosphere15 min earlier"and ,uh,hou..."he began. Transmission was cut off. A few seconds later kling saw more down arrows on the screen,this time signalling loss of tyre pressure.The ground flight controller Charles hobaugh radioed Rick,Rick made another attempt to contact mission control,replying to hobaugh with,"roger,uh,buh...".Again the transmission was cut off,along with it the flow of data from the shuttle. It was now some 30 seconds after 8:59am.Back at Johnson ,hobaugh radioed Rick :"columbia ,houston,commcheck.".There was no reply.NASA had lost columbia.
ANSWERS AT LAST:On march 19 a firefighter from Florida was walking a search line over hilly terrain near hemphill. He saw a square metal box painted black.It was columbia's Modular Auxillary DataSystem(MADS) Recorder .It had survived columbia's disintegration. The 28 track tape from the doomed spacecraft gave investigators the data they needed to determine that a breach had occurred in the leading edge of the left wing ,where some people believed the foam has struck. Still,doubts remained about whether a small piece of light weight material could have done such damage.
To resolve the issue,NASA conducted tests,using powerful nitrogen gas-powered cannon used to fire rubber projectiles at various aircraft components to test their resistance to bird strikes and similar unexpected collisions.On july 7 a block of foam weighing 760 gm-appprox size of chunk that hit columbia-was fired at a panel at 850kmph,the speed at which engineers had calculated it had probably hit.To the crowd of reports and NASA officials looking from a safe distance ,the foam's path was too swift to see,but the results were instantly obvious.A ragged 41-cm wide hole appeared on the lower side of the panel. The crowd gasped. The most complicated machine ever built got knocked out of the sky by 760 gm of foam.NASA was blamed for having a "broken safety culture".Frank buzzard director of the task force that operated as an liaison between the CAIB and NASA ,summed up the feelings of many when he said,"I am not sure we would have committed that next shuttle.Two of the last three had had foam come off(at launch).But the fact that we didn't try made us feel we let them down".
On jan 6,2004 NASA administrator Sean o'keefe announced that the rover spirit's landing site on mars would be named columbia memorial station,in memory of the seven lost astronauts
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