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.
I mentioned the SRBs for illustrative reasons. The cleavis joint has a much better design now. The previous flawed design was the main cause for the Challenger tragedy. That flawed design was not subtle. It was a botch job and lots of people knew it yet nothing was done until the Shuttle exploded.
If you think that the solid rocket motors are simple and safe you're wrong.
OK, Captain Science, explain -- using one and two syllable words, because I must be slow -- how we do a RTLS or a TAL after Main Engine Cut Off.
Why don't you ask NASA, they developed the contingencies.
My reading of this is that the MECO would now happen immediately after SRB separation.
I already asked if they had accelerometers on board whose data could be telemetered to ground. I would bet they do have many accelerometers since they would like to know that at least the main engines were healthy before attempting orbit after SRB separation. The accelerometers should be able to detect a significant impact, they do it on all jet engines very successfully.
Well, I've been going at it for awhile, I need to pit stop and refill the interplanetary coolers with beer.
... and what kind of shape is your car and it's tires in?
Last oil change?
How about tie rod ends and ball joints - any chance one of those will pull apart on the next chuck hole while driving at highway speeds on a two-lane road?
Dittemore's comments were very surprising, unexpected and disturbing.
Yeah, and when our great-great grandparents were discussing things it's a good thing they didn't say "ships can sink, we have no business allowing people to get on ships and try to get to a new world until we're absolutely certain they will be safe". With thinking like that we'd all be european.
Did I say safe?
Here's EXACTLY what I said: "[they are] the most reliable component of the entire shuttle ... these are ridiculously simple in construction ..."
Did I say safe?
I *did* say 'simple in construction' and, in contrast to a liquid-fueled rocket, this is true.
But did I say 'safe'?
You have just explained why the term Euro-weenies fits so many inhabitants of Yurp. All the brave ones with intelligence were willing and able to come over here.
The leak grew rapidly in width. The interior pressure in the SRB was 1000 PSI. The hot exhaust gasses were only kept in by 2 rubber "o" rings and some magic putty. The leak was forming an area where the sections were no longer attached to each other. How many seconds would it have taken for the leak to get so wide that the booster sections seperated? Not many I suspect.
I dont recall how much burn time they had left, but looking at the videos it seems they had a lot of fuel left after the explosion.
Has it been determined for sure that the flight control software codes that were active during re-entry were identical to the ones that were originally installed or uploaded by NASA? Are there hashes or keys that must be verified before being executed by the on-board computers?
Has there been any indication that any individual or group attempted to hack the onboard control systems or threatened to do so? Has anyone claimed credit?
Mind you, I'm not playing "Monday morning engineer." NASA must rethink it's safety and its contingencies if it is to survive. Average Joes will sour on spaceflight if too many people get killed. In "From the Earth to the Moon," in the investigation after the Apollo 1 fire, Frank Borman said that what killed Grissom, White, and Chaffee was "a lack of imagination. Nobody could imagine something like this could occur." I submit that there WERE things that could've been solved, had they been thought through. Yet in some cases, NASA has shown a great lack of imagination. Maybe they oughta have a few mothers-in-law on the staff. THEY'D think up all kinds of potential situations!
When operated in their appropriate temperature range these SRB's proved, time and time again, to be as reliable as required - they met operatinal specs.
Denigration of these inanimate items by alluding to 'only 2' "o" rings and calling the sealing compund 'magic putty' is low, really low.
I object on behalf of selfless "o" rings and pliable sealing compoundfs everywhere - and in every possible application ...
There is a LUG (Linux User Group) of about 25 people who were doing some open-source work for them on flight control software - it looks like maybe there was a version control snafu or something (like perhaps an Alpha or Beta release) got mixed in with the production code ...
Monday, 3 February, 2003, 00:41 GMT
At the latest press conference given by the US space agency, officials gave more details about temperature sensor readings during the last few minutes of the orbiter's flight.
She was proud to be representing her country
Astronaut Laurel Clark's aunt
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The new information came as Nasa officials confirmed that remains of all seven astronauts on board Columbia have been found.
Nasa has vowed to leave "no stone unturned" in its investigation into why the space shuttle disintegrated just minutes before its scheduled landing on Saturday.
Data reviewed by investigators showed the left side of the shuttle started to rise in temperature as it passed over California and New Mexico and that the shuttle was experiencing increased drag on the left-hand side of the vehicle.
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How Columbia broke up over Texas
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Space Shuttle Programme Manager Ron Dittemore said the detection of increased drag could have been an indication that the shuttle had lost heat-protection tiles or that the tiles had become uneven.
"But I have to caution you that this is a very fluid situation and what we understand today may change in the coming days," he stressed.
Experts are carrying out a painstaking analysis of the mass of data transmitted back from the shuttle in the last minutes of its flight.
Another key part of the investigation will be analysing the pieces of the shuttle which rained down over the southern US - a process likely to take months.
Possible damage to Columbia's protective thermal tiles on its left wing had already been flagged up as a cause for concern.
The wing was hit by a piece of insulating foam which peeled away from the external fuel tank a little more than a minute into Columbia's launch on 16 January.
The incident was spotted and checked at the time, Nasa officials said. But on Saturday they acknowledged they could not now rule out a connection.
As Americans mourned the deaths of the shuttle's seven astronauts, police teams scoured large areas in Texas for shuttle fragments.
Already accusations are being levelled that Nasa chiefs ignored a series of safety warnings.
But these were rejected by Nasa administrator Sean O'Keefe, who said every safety concern was tackled before a shuttle launch.
I was thinking that used iron diving bells might provide more cost-effective protection ... or better yet - '57 Chevy Belairs converted for space travel - those cars were virtually indestructable ...
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