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.
Maybe so.
If so it points to a larger flaw in the design.
But then I think we all knew this was a flawed design to begin with - a slapdash compromise, as Feynman pointed out.
Comment: Damage, although not evident, could still be present. Damage could also have been inflicted to the doors covering the wheeel wells. This looks to be a more likely scenario given the sequence of temp sensors losses and/or elevated temps followed by their loss too.
Do you understand that *some* of what they were indicating was the *loss* of the wiring to various temp sensors?
This last point is VERY important. It means something was buring through or something was being ripped away. Ripped away!
To instigate the amount of force needed to counter rotate the shuttle to the degree that had to occur to bring the inertial controls significantly online as they were
Comment: Attitude control. And they are online during this portion of flight continuously.
The attitude controls were correcting for an apparent roll to the left. As time went on - more correction, more Elevon deflection, was required.
reporting today would take more then a few tiles falling off. So if I am right that the tiles are a red herring, I
Comment: At mach 18 - I don't know the numbers ... depending on where the tiles were lost - or perhaps it was a corner of the wheel-well doors ...
have to envision a situation where there is a gradual loss of control. If the shuttle slowly began dipping the left
Comment: At no point (yet) did they lose control - more 'trim' was being required as TIME went on - indicating, perhaps that tiles were being stripped off slowly ...
wing toward the earth with the inertial control system trying to counter it, I envision a slow see-sawing of the
Comment: Attitude control. More and more input to the Elevons to 'correct' for a tendency of the shuttle to 'roll' left - due to drag on the left side.
left wing dipping down and then partially, but not completely, correcting the attitude, with the resulting heat measurements over the left wing surface and upper left
Comment: Here's where you're wrong. The corrections from the Elevons appear to work here (later - who knows).
Also - you can't account for the gradual loss of the temp sensors during this time.
The only thing that makes sense is - there was a hole on the wing - leading edge, underneath at the wheel well or top - somewhere.
side of the fuselage rising as it is exposed more and more to the atmosphere. I don't know where the telemetry
Comment: Nope. Roll is indicated to be corrected for (so far).
electronics and antenna are located, but it wouldn't
Comment: On top. surprise me if if was housed somewhere near the top of the fuselage and maybe even on the left hand side.
I believe the rise in temperatures after the loss of the telemetry dramatically increased, with the explosion that has been seen in the video all day long being the result.
Comment: This sentence doesn't make sense to me!
We don't have *any* data after the loss of telemetry (data transmitted from the shuttle).
I don't know how the elevon control structure works but a slow degredation of the attitude is consistent with the
Comment: BUT - the attitude was corrected .. but something was dragging - what was it?
Wheel well door? Tiles? Elevon damage? Internal hydraulics?
increasing temperature, before they it became critical, which occurred after the telemetry was lost.
Comment: At some point - the continued inputs for attitude adjustment made by the flight could no longer correct for more 'drag' on the left. At that point - they were in mortal danger!
Burn-up would follow ... as they shuttle was no longer in a nose-up position with it's best heat shields (on the bottom basically) doing their job ...
That is largely due to the politics surrounding its design. NASA's first approach probably would have been much more resiliant, but congress deemed it too expensive. As it exists today, the shuttle is not what anyone would wish for, it is what could be built given the political climate.
While it may have been possible to avert this disaster (but probably not), it would have required a certain amount of paranoia that would otherwise be paralyzing.
It is important to remember that shuttles aren't the only things that go down in flames. This sort of thing is just going to happen. In this case, NASA does not appear to have been negligent as they were preceding the Challenger incident.
I'm KIDDING!!
Dittemore is out of his league.
Maybe in the movies ... there are just too damn many technicians running around watching, observing, who *know* each other projects like this ...
Quality inspectors known as QA (Quality Assurance) or QRA (Quality Reliability Assurance) personnel check and double check and quite literally 'buy off' (stamp paperwork) for all work performed ...
I would rate this likelyhood as zero.
In this particular mission, there isn't much they could have done other than stay in orbit. They don't have in-flight tile repair/replacement capability. The orbital mechanics were such that they couldn't reach the ISS and even if they could they didn't have the docking adaptor or EVA suits to make an open crossing.
So you have to have someone go get them. And in the meantime try to hold out with the consumables you have and hopefully not have to jettison someone out the hatch to keep the others alive. Now, who would go get them? Shuttles take a minimum of weeks to get ready for launch. How many of the Columbia crew would have to be put out through the hatch to keep the others alive waiting for rescue? NASA doesn't like to think about those kind of contingencies. The Russians? I heard they had put Buran into mothballs or maybe were trying to sell it on e-bay? Soyuz? Do they have one ready to fire? Even if they did, well, you have a problem with overcrowding. Assuming one pilot to bring up the Soyuz, would there be room for seven others? If not, who goes and who stays behind to die?
Point is, we just don't have the infrastructure or financial commitment at this stage of our spaceflight development to keep these kinds of contingencies available. Like everything, you have to do the best you can with the resources you have, doing as much with it as possible within limits. That sometimes means taking risks, which, if things go wrong, always leaves you open to Monday morning quarterbacking.
This is not a minor event in my mind.
To all those of you picking on the software and sabotage angle or someone was tampering with controls remotely thru telemetry channels, I'm not buying it.
But, as I am all too often prone to say, Time will tell.
I know, but inclination changes can be made with thrust.
Using thousands of extremely fragile tiles to dissipate heat and protect an extremely fragile aluminium body seems very odd to me, but I am surely no scientist. I figure it all has to do with weight and cost, but it strikes me like we built a balsa wood car with pillows for bumpers. Granted, it's a stupid analogy, but riding a rocket is dangerous enough, why increase the risk to save a few bucks?
Prayers for the crew and folks on the ground....
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