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Posted on 02/02/2003 2:54:30 PM PST by NormsRevenge
NASA: Shuttle Temperature Rose Suddenly
By PAUL RECER, AP Science Writer
CAPE CANAVERAL, Fla. -
NASA (news - web sites) officials said Sunday that space shuttle Columbia experienced a sudden and extreme rise in temperature on the fuselage moments before the craft broke apart.
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NASA space shuttle program manager Ron Dittemore said the temperature rise — 60 degrees over five minutes in the mid-fuselage — was followed by an increased sign of drag that caused the shuttle's computerized flight control system to try to make an adjustment to the flight pattern.
Dittemore cautioned that the evidence was still preliminary, but that one of the possibilities was that there been damage or a loss of thermal tiles that protect the shuttle from burning up during re-entry into the Earth's atmosphere.
"We are making progress," Dittemore said, adding that the combination of new engineering data and an observer who reported seeing debris from the shuttle while it was still passing over California may create "a path that may lead us to the cause."
The shuttle broke up shortly before landing Saturday, killing all seven astronauts. Most of its debris landed in eastern Texas and Louisiana.
Earlier Sunday, NASA administrator Sean O'Keefe named a former Navy admiral to oversee an independent review of the accident, and said investigators initially would focus on whether a broken-off piece of insulation from the big external fuel tank caused damage to the shuttle during liftoff Jan. 16 that ultimately doomed the flight 16 days later.
"It's one of the areas we're looking at first, early, to make sure that the investigative team is concentrating on that theory," O'Keefe said.
The insulation is believed to have struck a section of the shuttle's left side.
Dittemore said the engineering data showed a temperature rise in the left wheel well of the shuttle about seven minutes before communication was lost with the spacecraft. One minute later, there was an even more significant temperature rise in the middle to left side of the fuselage.
The drag on the left wing began a short while later, causing the shuttle's automated flight system to start to make adjustments.
"There may be some significance to the wheel well. We've got some more detective work," Dittemore said.
The manufacturer of the fuel tank disclosed Sunday that NASA used an older version of the tank, which the space agency began phasing out in 2000. NASA's preflight press information stated the shuttle was using one of the newer super-lightweight fuel tanks.
Harry Wadsworth, a spokesman for Lockheed, the tank maker, said most shuttle launches use the "super-lightweight" tank and the older version is no longer made. Wadsworth said he did not know if there was a difference in how insulation was installed on the two types of tanks.
Wadsworth said the tank used aboard the Columbia mission was manufactured in November 2000 and delivered to NASA the next month. Only one more of the older tanks is left, he said.
O'Keefe emphasized that the space agency was being careful not to lock onto any one theory too soon. He vowed to "leave absolutely no stone unturned."
For a second day, searchers scoured forests and rural areas over 500 square miles of East Texas and western Louisiana for bits of metal, ceramic tile, computer chips and insulation from the shattered spacecraft.
State and federal officials, treating the investigation like a multi-county crime scene, were protecting the debris until it can be catalogued, carefully collected and then trucked to Barksdale Air Force Base in Louisiana.
The effort to reconstruct what is left of Columbia into a rough outline of the shuttle will be tedious and painstaking.
When a shuttle piece was located this weekend, searchers left it in place until a precise global position satellite reading could be taken. Each shuttle part is numbered; NASA officials say experts hope to trace the falling path of each recovered piece.
The goal is to establish a sequence of how parts were ripped off Columbia as it endured the intense heat and pressure of the high-speed re-entry into the atmosphere.
At least 20 engineers from United Space Alliance, a key NASA contractor for the shuttle program, were dispatched to Barksdale for what is expected to be a round-the-clock investigation.
Other experts, including metallurgists and forensic medicine specialists, are expected to join the investigation. Their focus will be on a microscopic examination of debris and remains that could elicit clues such as how hot the metal became, how it twisted and which parts flew off first.
In addition to NASA's investigation, O'Keefe named an independent panel to be headed by retired Navy admiral Harold W. Gehman Jr., who previously helped investigate the 2000 terrorist attack on the USS Cole (news - web sites).
Gehman's panel will also examine the Columbia wreckage, and come to its own conclusions about what happened. O'Keefe described Gehman as "well-versed in understanding exactly how to look about the forensics in these cases and coming up with the causal effects of what could occur."
Joining Gehman on the commission are four other military officers and two federal aviation safety officials.
Officials used horses and four-wheel-drive vehicles to find and recover the shuttle pieces. Divers were being called in to search the floor of Toledo Bend Reservoir, on the Texas-Louisiana line, for a car-sized piece seen slamming into the water.
Some body parts from the seven-member astronaut crew have been recovered and are being sent to a military morgue in Dover Air Force Base in Delaware.
Columbia came apart 200,000 feet over Texas while it was streaking at more than 12,000 miles an hour toward the Kennedy Space Center (news - web sites). A long vapor trail across the sky marked the rain of debris.
He RUNS away from the question of why he didn't ask for telescopic investigation of possbile left-wing damage on ascent - mainly because, IMO, he doesn't want to deal with the problem of what to do if damage is shown. This is a $5,000,0000,0000 vehicle and he doesn't want to consider it's endangerment. Sure, delaying descent would have been awkward, particularly for NASA. But, I submit, it would have been easier than Apoolo XIII (where the cover page of a manual was essential to preserving breathable oxygen). And we'd still have 4 orbiters.
When Discovery had some problem with the vertical stabilizer, NASA tried to look at it with ground telescopes but the resolution wasn't good enough to do any good. He made a good call by not wasting time performing a fruitless task. However, I don't know why an EVA (extra vehicular activity) was not scheduled in order to make a visual inspection.
I second this motion.
There is no such thing as an on-orbit tile repair kit. Everyone of the 30,000 or so tiles is custom-made for its location. There is no adhesive that can be used in the cold and vaccum of space and yet will survive the heat of re-entry.
If there is blame to attach it seems to be here. To the casual observer this is an astounding revelation.
No EVA suits. No means to repair the heat shield.
Amazing.
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