The final moments on board space shuttle Columbia were revealed today as NASA published transcripts of its last radio contacts with mission control.
The shuttle blew up as it entered the atmosphere above Texas on February 1st, killing all seven astronauts on board.
The first bad news came about six or seven minutes before the disaster, when Mr Jeff Kling, the crew systems officer, reported a sudden and unexplained loss of data from the spacecraft's sensors.
"I just lost four separate temperature transducers on the left side of the vehicle, the hydraulic return temperatures," he said.
Moments later, guidance and navigation officer MR Mike Sarafin said Columbia's wing was encountering drag, or increased wind resistance.
Flight director Mr Leroy Cain asked if everything else was normal, and Mr Sarafin assured him: "I don't see anything out of the ordinary."
There followed a short indistinct call from the spacecraft and then Mr Kling said the landing gear tyres had lost pressure.
Capsule communicator Mr Charlie Hobaugh then addressed the spacecraft: "And Columbia, Houston, we see your tyre pressure messages and we did not copy your last.
Columbia commander Mr Rick Husband's response - "Roger, buh" - was abruptly cut off. It was 7.59 a.m. (1.59 p.m. Irish time).
Flight controllers on the ground in Houston began reporting a string of further problems.
There was evidence of small collisions on the tail, and signals were cut from the nose landing gear and the right main landing gear.
Then more sensors were lost and the drag increased on the left. Mr Hobaugh launched into a series of radio calls to Columbia.
There was no response as the minutes ticked away towards the planned landing time at Florida's Kennedy Space Centre.
"MILA (the Kennedy spacecraft communication centre) is not reporting any RF (radio frequency) at this time," said Mr Bill Foster, a ground controller.
"OK," said Mr Cain, who then asked hopefully when a radar signal was expected.
"One minute ago, flight," came the response from Mr Richard Jones, flight dynamics officer.
The communication checks continued. So did the silence. A radar station near the Kennedy centre then said it was putting its radar into "search mode".
"We do not have any valid data at this time," said Mr Jones. He said there was a "blip" but that it was bad data.
Then followed a long pause. Mr Cain's next phrase marked the lack of hope: "Lock the doors." This meant nobody could leave Mission Control or even make phone calls.
For the next few hours, the engineers had to ignore the certain loss of the crew and store the data in their computers, finish reports and then write personal accounts of what they saw, heard and did.
AP