Posted on 02/01/2003 4:25:45 PM PST by Sub-Driver
Columbia's Problems Began on Left Wing By THE ASSOCIATED PRESS
Filed at 6:56 p.m. ET
CAPE CANAVERAL, Fla. (AP) -- Investigators trying to figure out what destroyed space shuttle Columbia immediately focused on the left wing and the possibility that its thermal tiles were damaged far more seriously than NASA realized by a piece of debris during liftoff.
Just a little over a minute into Columbia's launch Jan. 16, a chunk of insulating foam peeled away from the external fuel tank and smacked into the ship's left wing.
On Saturday, that same wing started exhibiting sensor failures and other problems 23 minutes before Columbia was scheduled to touch down. With just 16 minutes remaining before landing, the shuttle disintegrated over Texas.
Just a day earlier, on Friday, NASA's lead flight director, Leroy Cain, had declared the launch-day incident to be absolutely no reason for concern. An extensive engineering analysis had concluded that any damage to Columbia's thermal tiles would be minor.
``As we look at that now in hindsight ... we can't discount that there might be a connection,'' shuttle manager Ron Dittemore said on Saturday, hours after the tragedy. ``But we have to caution you and ourselves that we can't rush to judgment on it because there are a lot of things in this business that look like the smoking gun but turn out not even to be close.''
The shuttle has more than 20,000 thermal tiles to protect it from the extreme heat of re-entry into the atmosphere. The black, white or gray tiles are made of a carbon composite or silica-glass fibers and are attached to the shuttle with silicone adhesive.
If a spaceship has loose, damaged or missing tiles, that can change the aerodynamics of the ship and warp or melt the underlying aluminum airframe, causing nearby tiles to peel off in a chain reaction.
If the tiles start stripping off in large numbers or in crucial spots, a spacecraft can overheat, break up and plunge to Earth in a shower of hot metal, much like Russia's Mir space station did in 2001.
Dittemore said that the disaster could have been caused instead by a structural failure of some sort. He did not elaborate.
As for other possibilities, however, NASA said that until the problems with the wing were noticed, everything else appeared to be performing fine.
NASA officials said, for example, that the shuttle was in the proper position when it re-entered the atmosphere on autopilot. Re-entry at too steep an angle can cause a spaceship to burn up.
Law enforcement authorities said was no indication of terrorism; at an altitude of 39 miles, the shuttle was out of range of any surface-to-air missile, one senior government official said.
If the liftoff damage was to blame, the shuttle and its crew of seven may well have been doomed from the very start of the mission.
Dittemore said there was nothing that the astronauts could have done in orbit to fix damaged thermal tiles and nothing that flight controllers could have done to safely bring home a severely scarred shuttle, given the extreme temperatures of re-entry.
The shuttle broke apart while being exposed to the peak temperature of 3,000 degrees on the leading edge of the wings, while traveling at 12,500 mph, or 18 times the speed of sound.
A California Institute of Technology astronomer Anthony Beasley, reported seeing a trail of fiery debris behind the shuttle over California, with one piece clearly backing away and giving off its own light before slowly fading and falling. Dittemore was unaware of the sighting and did not want to speculate on it.
If thermal tiles were being ripped off the wing, that would have created drag and the shuttle would have started tilting from the ideal angle of attack. That could have caused the ship to overheat and disintegrate.
Dittemore said that even if the astronauts had gone out on an emergency spacewalk, there was no way a spacewalker could have safely checked under the wings, which bear the brunt of heat re-entry and have reinforced protection.
Even if they did find damage, there was nothing the crew could have done to fix it, he said.
``There's nothing that we can do about tile damage once we get to orbit,'' Dittemore said. ``We can't minimize the heating to the point that it would somehow not require a tile. So once you get to orbit, you're there and you have your tile insulation and that's all you have for protection on the way home from the extreme thermal heating during re-entry.''
The shuttle was not equipped with its 50-foot robot arm because it was not needed during this laboratory research mission, and so the astronauts did not have the option of using the arm's cameras to get a look at the damage.
NASA did not request help in trying to observe the damaged area with ground telescopes or satellites, in part because it did not believe the pictures would be useful, Dittemore.
Long-distance pictures did not help flight controllers when they wanted to see the tail of space shuttle Discovery during John Glenn's flight in 1998; the door for the drag-chute compartment had fallen off seconds after liftoff.
It was the second time in just four months that a piece of fuel-tank foam came off during a shuttle liftoff. In October, Atlantis lost a piece of foam that ended up striking the aft skirt of one of its solid-fuel booster rockets. At the time, the damage was thought to be superficial.
Dittemore said this second occurrence ``is certainly a signal to our team that something has changed.''
OK, I'll make this VERY SIMPLE.
The basic problem is that STS-107 had no MMUs, and most importantly, it carried NO 'SPACE' SUITS!
Each of the astronauts is issued a personalized, fitted pressure suit that has a portable, short-time A/C and telemetry pack that you see them carrying when they do the famous march to the shuttle. Those little packs are disconnected when they are placed in their flight seats and their pressure suits are connected to the shuttle's A/C and power... the portable units are then REMOVED from the shuttle as useless weight! Even if they were left on board, they do not carry oxygen... they take that from the ambient atmosphere and merely pressurize it to the suit.
The pressure suits are not intended or designed to be EVA suits. They lack the insulation, telemetry equipment, radios, Oxygen tanks, cooling and heating ducting, constant pressure joints, and sun shields an EVA suit requires. They are provided as a safety measure only to assure survival in the event of a hull breech that causes the loss of air and pressure during takeoff and landing. The shuttle was designed to be a "shirt sleeve" environment similar to a jet airliner but NASA has never taken the planned final step and launched a shuttle with astronauts without the pressure suits.
They cannot be modified to become EVA suits.
In addition, an EVA without a MMU and a proper EVA suit IS a violation of the laws of physics. Specifically, how would your make-shift inspector move around? The Shuttle is non-magnetic so magnet soled space shoes wouldn't work. Jumping requires a properly placed fixed object to kick-off from (nothing sticking out under there, you know). Assuming our valiant space-walker does kick-off of the non-existant object in the exactly right trajectory to take him to the left wing, how does he stop? Perhaps one of the ladies has smuggled a can of hair spray on board that can be used as a mini-MMU???
OH, and how, exactly, is he or she going to breathe? The pressure suits require an umbilical to the shuttle's Life Support systems. The supplied cabin umbilicals are only long enough to reach across the cabin so that in the event of decompression, they can still reach controls. Are you going to collect all of the seven umbilicals and DUCT TAPE them together to get sufficient length to reach from a Life Support port, out the door (Thank God its on the left side), along the left wing to the damage area? Oops... the Life Support ports are INSIDE the cabin. We have to leave the door open. Bummer, we're using everyone else's umbilicals to get the length we need... I guess they won't need to breathe while were outside poking around.
An EVA without proper preparation and equipment is impossible.
Is that factual and practical enough for you?
Right.
And how would they track the Columbia in a pitched orbit to the North-East or South East (depending on its position in orbit), moving at 500 degrees per hour, with these equatorially mounted, ASTRONOMICAL telescopes designed to follow stars at 15 degrees per HOUR with only a West vector? Satellite tracking telescopes do not generally have the resolution to distinguish any detail at all. We are lucky to get fuzzy shapes.
The shuttle would have to have shut down all operations, closed the bay doors, and turned turtle so the bottom of the wings would be toward the Earth before any of these ground based telescopes could see a thing.
And finally, the only thing to be learned by such an examination was a moot point. IF the tiles were too badly damaged, the astronauts were dead, one way or the other. If they aren't too badly damaged, the shuttle will survive re-entry. A ground based examination MAY show the damage but the DEPTH into the insulation tiles could not be judged from such a distance. You cannot even SEE anything except a possible color differential and, according to John Jamieson, the most important tiles are actually Black Glaze on Black ceramic foam. Only the farther back, less critical tiles are Black on white.
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