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.
Again, NASA has performed the risk/bene analysis - and, according to the brief numbers I looked at, we're still above the break even point.
That, son, is cold, hard reality talking - and even at that rate we've got hundreds of people lining up to go into space. Wish I were able to sell tickets into a gig like that ...
Simply driving down the street is a HIGHLY calculated risk - any activity a thinking, breathing individual undertakes, even sitting slumped in an easy chair, is a 'calculated risk'.
These 'risks' that Dittermore and his crew decided were acceptable were based, now, on twenty or so chronological years, but, collectively, with all the members of the staff he's got working with him probably amounts to more like one thousand years accumulated experience ... backed by the 'numbers' to justify it.
Quite frankly - I am deeply impresed with the horsepower they are able to harness on take-offs - my hat is off to the rocket-motor designers!
What is it you *really* desire?
Do you desire to see what kind of training he had in four, six or eight years in an educational institution?
Schooling twenty years ago has got to have *very* little bearing on his present abilities, although, they may have given him the good, hard-core basics upon which to build in his carreer at NASA.
So, let's get down to what it is you *really* want ...
Call 9 1 1 huh?
Right.
(Welcome to the big leagues kid - where it is a high wire act *without* a net ...)
As I got older, NASA became just another "government program". And then somehow, Space became less of a priority, and my apologies, it became sort of a sideshow. There was no real goal, at least it seemed that way to us common folk.
Yes, the shuttle went up, and then it came down. It delivered satellites, and people did experiments. It all seemed so routine. It all seemed, sadly, an anti-climax. We'll probably never build the "best". We seem to have so many "priorities" and "domestic needs" here on Earth, that there is very little left over.
I still wonder what we could have done, had we had the will. But I still have fond memories of assembling my Saturn V model and believing that we could do it! But, I am much older, wiser, and more realistic I guess. I guess we shouldn't expect so much from our space program. Heck, it's still better than 160+ other countries space programs!
It would surely increase it,but not as much as some people might think. We already have more than 2 shuttles,so we wouldn't have to build a special one. We already have plenty of astronauts,and they are getting paid at the same rate regardless of if they are sitting in some "ready shack",or out on the golf course. Ditto with the launch crew. They ain't hired by the hour. All are already on the payroll,and I doubt any of them would object to being placed in a ready status on call.
Also how would we be able to get the rescue ship to connect with the other one that's in trouble, so the occupants from the one can transfer to the other without going adrift in space? There's nothing to hook.
A astronaut from one ship could EVA to the other ship with a line they others could use to cross the gap. They could also use some sort of flexible hose similiar to what airliners use as a "tunnel" to connect the two ships,and the astronauts could just walk across from one to the other using the tunnel. --------------------------------------------------------------------------------
I merely quoted them.
What we see in NASA re the other vulnerabilities of the Shuttle incuding tile damage similar to what is described in this part of the Challenger Commission report. Here is another quote. Notice the part "they got away with it last time."
EARLY DESIGN
The Space Shuttle's Solid Rocket Booster problem began with the faulty design of its joint and increased as both NASA and contractor management first failed to recognize it as a problem, then failed to fix it and finally treated it as an acceptable flight risk.
Morton Thiokol, Inc., the contractor, did not accept the implication of tests early in the program that the design had a serious and unanticipated flaw. NASA did not accept the judgment of its engineers that the design was unacceptable, and as the joint problems grew in number and severity NASA minimized them in management briefings and reports. Thiokol's stated position was that "the condition is not desirable but is acceptable."
Neither Thiokol nor NASA expected the rubber O-rings sealing the joints to be touched by hot gases of motor ignition, much less to be partially burned. However, as tests and then flights confirmed damage to the sealing rings, the reaction by both NASA and Thiokol was to increase the amount of damage considered "acceptable." At no time did management either recommend a redesign of the joint or call for the Shuttle's grounding until the problem was solved.
FINDINGS
The genesis of the Challenger accident -- the failure of the joint of the right Solid Rocket Motor -- began with decisions made in the design of the joint and in the failure by both Thiokol and NASA's Solid Rocket Booster project office to understand and respond to facts obtained during testing.
The Commission has concluded that neither Thiokol nor NASA responded adequately to internal warnings about the faulty seal design. Furthermore, Thiokol and NASA did not make a timely attempt to develop and verify a new seal after the initial design was shown to be deficient. Neither organization developed a solution to the unexpected occurrences of O-ring erosion and blow-by even though this problem was experienced frequently during the Shuttle flight history. Instead, Thiokol and NASA management came to accept erosion and blow-by as unavoidable and an acceptable flight risk.
Note that tile damage at launch has been regarded as unavoidable and an acceptable flight risk until now.
Specifically, the Commission has found that:
1. The joint test and certification program was inadequate. There was no requirement to configure the qualifications test motor as it would be in flight, and the motors were static tested in a horizontal position, not in the vertical flight position.
2. Prior to the accident, neither NASA nor Thiokol fully understood the mechanism by which the joint sealing action took place.
3. NASA and Thiokol accepted escalating risk apparently because they "got away with it last time." As Commissioner Feynman observed, the decision making was:
"a kind of Russian roulette. ... (The Shuttle) flies (with O-ring erosion) and nothing happens. Then it is suggested, therefore, that the risk is no longer so high for the next flights. We can lower our standards a little bit because we got away with it last time. ... You got away with it, but it shouldn't be done over and over again like that."
4. NASA's system for tracking anomalies for Flight Readiness Reviews failed in that, despite a history of persistent O-ring erosion and blow-by, flight was still permitted. It failed again in the strange sequence of six consecutive launch constraint waivers prior to 51-L, permitting it to fly without any record of a waiver, or even of an explicit constraint. Tracking and continuing only anomalies that are "outside the data base" of prior flight allowed major problems to be removed from and lost by the reporting system.
5. The O-ring erosion history presented to Level I at NASA Headquarters in August 1985 was sufficiently detailed to require corrective action prior to the next flight.
6. A careful analysis of the flight history of O-ring performance would have revealed the correlation of O-ring damage and low temperature. Neither NASA nor Thiokol carried out such an analysis; consequently, they were unprepared to properly evaluate the risks of launching the 51-L mission in conditions more extreme than they had encountered before.
Not exactly, I'm wondering if they both could have moved to meet in the middle.
If so, the ISS doesn't really have any propulsion capabilities, only small thrusters for stationkeeping.
The ISS has a propulsion module made by the Russians. I can't recall the name, but it starts with a "Z."
On top of that I doubt it would stay together if you tried to move it. It's not designed to move.
How else would the orbit get reboosted? Shuttles were routinely used to reboost the ISS orbit.
But, consider this: *no* failurs had occurred of the SRB up until the Challenger accident. None. Zip. Zero.
The appearance of a little smoke from a rocket joint does not indicate a fail or a fault, this was normal for this series of rockets. In fact, it could be consdered analougous to the 'rings' seating in a car - the "o" rings must first seat, after which they seal.
Again the Risk/Benefit aspect must be considered - treat the booster within proper parameters, and, she will perform as designed.
The mistake came when the SRB was operated outside 'her' limits paramets - a temperature below which the "o" ring would not remain pliable enough, where the normally pliable sealing compound became hardened - and failed to seal-in the high-pressure combustion-product gases that form with the SRB. A failure to seal in those gases - allowing them to escape - was the problem ...
He (or is it she - I'm confused now) is in for it when He (or is it she) gets back on the board ...
!Kidding!
Not exactly, I'm wondering if they both could have moved to meet in the middle.
If so, the ISS doesn't really have any propulsion capabilities, only small thrusters for stationkeeping.
The ISS has a propulsion module made by the Russians. I can't recall the name, but it starts with a "Z."
On top of that I doubt it would stay together if you tried to move it. It's not designed to move.
How else would the orbit get reboosted? Shuttles were routinely used to reboost the ISS orbit.
Here are some answers:
You could not meet in the middle because both vehicles have less that 1000ft/sec of delta-V. (In fact, I think the station has only about 300 ft/sec.) The ISS can reboost, but it up higher than the Orbiter was -- 220 or 250 NMI. Don't remember exactly. Further, it is up high like that to minimize atmospheric drag (aerodrag drops by a factor of 10 every 10 NMI you go up.
ISS does have a propulsion module but they have to be very careful using it lest they damage the station. They generally run it a low thrusts. It is only intended for reboost. Yes, Shuttles reboost the Station. It is a hairy procedure that uses the Shuttle's reaction control system, not the OMS. It takes up to an hour, and only raises the ISS's orbit by a mile.
What's the mortality rate for astronauts as a percentage of the total astronaut corp versus the general public (consider only accidental deaths for this exercise)?
What's the mortality rate for NASCAR drivers?
That wouldn't help much either. Okay, let's say you've got a space suit and a long tether. *Now* what?
It's not as easy to maneuver in zero-G as you'd think. The outside of the shuttle is not studded with hand-holds. Magnetic boots won't work on much of it, and especially won't work on the tile area. So what's your plan, float around at random and hope you swing past the spot you want to look at or work on?
Yes, I know NASA developed an MMU to help astronauts move around outside, but now you've added *another* piece of heavy, dangerous (it needs to be fueled) equipment to be carried on every flight "just in case", along with all conceivable tools, replacement equipment, raw materials, etc. etc. etc.
Hindsight is always 20-20. And trying to be prepared for *every* contingency is simply unworkable. Imagine trying to carry a car repair shop in your car with you on every trip...
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