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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.
Nice work. It seems encompass the same area as the first few heat sensor failures.
"Because of evidence of plasma flow on the lower wing trailing edge and elevon landing edge tiles (wing/elevon cove) at the outboard elevon tip and inboard elevon, the low-temperature tiles are being replaced with fibrous refractory composite insulation (FRCI-12) and high-temperature (HRSI-22) tiles along with gap fillers on Discovery and Atlantis. On Columbia only gap fillers are installed in this area."
The Shuttle consists of an Orbiter (what we lost yesterday), 2 main engines called SSME's, 2 External Tank (big orange liquid tank), 2 Solid Rocket motors, Ammonium Perchlorate mixture, and the Solid Rocket Boosters (total package) by Morton Thiokol in Utah, and many other elements. Rockwell build all 5 Orbiters, Main Engines built by Rockedyne (some components by Pratt & Whitney) The Shuttle cost also consists of fuels, launch and landing capabilities, turnaround, upgrades to Shuttles, etc. Be more specific and we perhaps can answer you.
That doesn't mean they couldn't have had it. It just means that several sombodies failed in their duty to convince the right people that this was a neccessary safety move.
For some reason - the lines from these temp sensors (be they thermistors or thermocouples) were "burned through" (my words) at some point where they went back into the electronics bay where eventually they are all 'read' by the electronics aboard the Shuttle and their readings sent back to NASA.
Couple this with the excess drag on the left wing and we have our culprit.
Note to NASA: On future Space Shuttle flights, equip the astronauts with longer teathers.
Woulda coulda shoulda ... they didn't though ...
LOL. After Challenger, I sat through three years of Space Shuttle management meetings listening to "bottoms up" reviews of ALL shuttle elements. Obviously, you understand.
I have seen and held them in my own hands, and also at one time was able to tour a manufacturing facility.
I am inclined to believe a combination of events occurred which led to structural failure. Whether it is tile damage that was not readily apparent visually, and only was the first item to begin to fail during re-entry, or which may have then led to either a hydraulic or sensory control which in turn caused the shuttle guidance system to react to its inputs and cause the shuttle to deviate its flight orientation in response to the anomalies that occurred.
If a tile(s) failed, and in effect, allowed a burn-thru of the fuselage or even an excessive heating near certain controls, then there is no way to counteract that.
At that point, it is a loss of mission and crew condition.
The tires being inflated as part of the re-entry process also needs to be looked at in detail. This seem to be the last piece of active communication between mission control and the shuttle. Could the left side wheel experienced some sort of failure in and of itself or was the potential tile issue the precipitant of all that followed.
I'm in the dark as much as all of the rest of you.
But I'm not gonna put the candle out quite yet.
The fact that 80 seconds after launch , debris struck the wing is not good. I have seen cracked tiles and tiles that may have sustained a dimpling or gouging effect. At what point, are they rendered sufficiently impaired and thus suspect, I don;t know.
Without careful inspection, you can not say 100% that the tile is still able to adequately perform its function. IMO
The issuance of magic wands is extra?
Probably correct. Just pointing out a possible piece of the puzzle.
When a system fails the first place you look is the last thing that changed.
BTW...Whoraldo is really over the top. He just started his show asking why they didn't have time to inspect the tiles during the two week they were docked at ISS! Does this guy even bother trying to learn the facts?
Practically speaking, an activity to rival the main string of missions themselves ...
Why not just launch *two* shuttles for each mission - one as a rescue vessel?
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