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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.
I'll bet you they won't -- and *shouldn't*.
Except in the case of an obvious major malfunction, the abort procedure is likely to be far more dangerous (and untested) than just continuing with the flight plan. It would be irresponsibly risky to do an abort just because something "looks" unusual. It would be like having everyone parachute out of a commercial 747 whenever the pilot gets an unexpected warning light -- *way* overreaction, and more risky than the actual problem in most cases, not to mention damned expensive.
Allow me to referee -- he's not wrong, and you're making an ass of yourself. YOUR OWN POST agrees with what he wrote. Furthermore, you owe him an apology.
Your "facts" cannot be trusted. Truce, you shoot from the hip, and supply absolutely wrong information.
What have you been smoking?
He wrote that RTLS is no longer an option after "four minutes into the mission". You claimed he was "wrong" on that count and as "proof" you quoted NASA, and even personally highlighted the portion where they said that RTLS had to be done "between lift-off and approximately four minutes 20 seconds". So yeah, just as he said, after about four minutes into the mission, to the nearest minute, you can no longer do an RTLS. YOUR OWN NASA QUOTE CONFIRMS IT.
So what on earth are you babbling about when you claim that he's "absolutely wrong"?
Perhaps you're boneheadedly misunderstanding what he meant when he wrote, "You have to opt for an RTLS or a TAL almost immediately after liftoff", but in context with the "four minutes" comment that immediately followed that, it's quite clear that "almost immediately" means "in the first few minutes", not the first few seconds, if that's how you're misreading it.
This was all started when he wrote, correctly, "After Main Engine Cut Off there was literally nothing NASA could do". And he's right. MECO is well after the 4:20 limit beyond which RTLS is not an option, and 100 seconds after that, TAL is not an option either. He was entirely correct.
You on the other hand were dead wrong when you wrote, "My reading of this is that the MECO would now happen immediately after SRB separation". No, it wouldn't. MECO means Main Engine Cut Off. If you cut off the main engines "immediately after SRB separation", you would now have no thrust to speak of (the OMS thrust would barely be noticeable, and not last long), and would be in "flying brick" mode, traveling at several Mach eastward out over the Atlantic, looking forward to a very wet landing.
So when he wrote, "I suggest you come back to this discussion when you can make informed recommendations", it seems excellent advice.
I love it when such a pompous ass is delivered his due.
So do I, and now you've been delivered your due.
This question came up repeatedly in the Saturday press conference. Dittemore's answer was consistent - there are no contingency plans for this scenario except for a design which does not allow it to happen in the first place.
BUMP
One thing we do know for sure though is that at least we can rest assured that no Microsoft code was involved in the Shuttle flight control system. That in itself eliminates one of the biggest uncertainties in the integrity of the code.
Sadly, "should" will not be the main issue in how NASA responds to this tragedy since technical righteousness has little to do with how organizations adapt to disasters. Assuming that tile damage is found to be a contributing factor to this loss, it would likely be determined that this was a fluke accident and that current procedures are within acceptable risk tolerances and should not be changed. However rational this conclusion would be, it would not be the outcome. Something substantial will have to change before another shuttle is launched.
No manager will accept a risk of repeated failure, no matter how remote the possibility. This heightened aversion to repeated risk has been studied extensively. The incident investigation panel will find something that could have been done to prevent this loss and procedures will be changed to avert this same type of incident in the future, no matter how irrational the solution may be. The outcome of this investigation will be chosen by the managers or even the politicians, not by the engineers.
On descent the shuttle does "roll reversals" to lose speed. As I understand these, it will roll right-then-left for the first then left-then-right for the second. I would expect that these different "roll-reversals" stress the left and right wings differently. So, if you knew of damage to the left wing, would you consider changing the reentry scheme - doing more of one type than the other?
Just a question - which never got asked...
I don't claim to have solutions. Just suggestions. How many more questions never got asked? How many more suggestions never got made?
Good evening and sorry about the delay ...
What likely caused the destruction of the craft - first causal agent, a loss of a component in the exterior Heat Protection System BUT that was only the first in a string of events leading up to the destruction of STS-107 and I'd like to get into that this evening in our continueing lecture series ...
Whether this was on the underside wing or the topside of the wing or the leading edge, we have now have a better idea today, with the release of the STS-107's launch video from NASA and described in this post.
Something, presumed to be insulation foam from the main tank appears to strike the leading of the left wing and then the remains of this object proceeds in what appears to be a shower smaller debris (particles) under the wing and past the shuttle.
This just in via CH 4 Fox locally: A space shuttle tile was discovered on Hyw 67 in Alvarado Tx.
Okay, so we have the causal agent - and that leads to an unclean airfoil/wing on the left side. This forced, upon reentry, the rolling or yawing motion to the left that we discovered today was even more severe than we learned yesterday. In feact, it got so bad the small thrusters began to fire to corect for the yawing and rolling that was taking place. NASA reported to day that it weasn't so much how much yaw and roll had to be corrected for, but rather at what rate these corrections were becoming necessary!
We can then add in the temp msmts coupled with the later loss of various temp msmt points - if I knew where the wiring was run - what conduits and such - this is the smoking gun, so to speak, where hot plasma was literally pouring in and now consuming/melting/varporizing any and all combustibles/materials exposed to that plasma coming via a small (initially) and progressively larger opening first allowed to form because a component of the TPS (heat tile) was damaged ...
To make a long story short - the space craft was ultimately unable to correct for the ever increasing amount of roll and yaw the craft wanted to do - because of an unclean/deformed/consumed by 3000 degree F plasma - exactly the thing that the heat tiles wee supposed to protect the underlying aluminum frame from ever 'seeing' ...
Summarizing:
First Causal agent: loss of tile
Leads to: unstable platform that required ever-increasing amounts of 'stick' to correct the craft attitude
Leading to: a fatal yaw and perhaps roll to the left and exposing the right side of the craft to full effects of Mach 18 flight (along with the high temps it *was* not designed to handle in that attitude)
Ending in: Failure of the right side wall (melts/burns away)
And finally: the hydrazine fuel, oxygen storage tanks explode ... finishing off structure the craft had ...
Loss of tile/damage to tile: 95%
Loss of other system (hydraulics, Elevon): 5%
- - - - - - -
Loss/damage to tile on leading wing edge 50%
Loss/damage to tile on bottom: 40%
Loss/damage to tile on top: 10%
- - - - - - -
Boy you're persistent. Since no one else bothered to answer your question I'll try. First, call NASA/JSC and they'll send you Ron Dittemore's Bio.
I'm not exact with this but here's a stab on his background. Ron is not a hardware guy. Ron spent many years in Mission Operations, and achieved Flight Director status for Space Shuttle missions. Sometime after the Challenger accident, NASA was "encouraged" to utilize Astronaut types in it's Management (hardware/manufacturing) side of the house. Today, you will notice that most managers you see did not grow up on the hardware side of the house but come from backgrounds as Astronauts and Flight Directors.
In the early/mid '90's Dittemore was selected to be Deputy Orbiter Project Manager... then became Orbiter Project Manager after the last Orbiter was delivered (Challenger replacement), and in the last couple of years he has been the Space Shuttle Program Manager.
Also, a good manager IMO, is one who knows WHO to trust, knows the RIGHT questions to ask, listens to his experts. IMO, it has very little to do with his particular educational piece of paper, even though I'm sure he's an engineer, either aerospace or mechanical. I've sat in many meetings with Dittemore and give him high marks for his abilities as a problem solver. I hope this helps, and perhaps NTWK can add to my meager knowledge, if he so desires.
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