CAPE CANAVERAL, Fla. (AP) - Just before it disintegrated, space shuttle Columbia experienced an abnormal rise in temperature and wind resistance that forced the craft's automatic pilot to make rapid changes to its flight path - possible evidence that some heat-protection tiles were missing or damaged, NASA said Sunday. Engineers began assembling a grim puzzle from debris recovered in Texas and Louisiana, and disclosed computerized data showing that the unusual events before Saturday's accident occurred in the wheel well and fuselage on the left side of the shuttle - the same side hit by a piece of fuel-tank insulation during the launch 16 days earlier.
Shuttle program manager Ron Dittemore cautioned the data was preliminary but said the combination of events and data suggest that the thermal tiles that protect the shuttle from burning up during re-entry may have been damaged on Jan. 16.
''We've got some more detective work. But we're making progress inch by inch,'' Dittemore said, adding engineers are trying to extract 32 seconds more of computerized data from the doomed spacecraft.
As engineers pinpointed the exact satellite locations of debris, Robert Cabana, director of flight crew operations at the Johnson Space Center, said remains from all seven of the astronauts had been found. Later, Cabana said in a statement that he had been misinformed and that NASA could not confirm that remains from each of the astronauts were recovered. Dittemore said earlier in the mission, NASA had aggressively investigated the possible effects of the impact from the fuel tank's foam insulation and concluded ''it did not represent a safety concern.''
''As we gather more evidence, certainly the evidence may take us in another direction,'' he said.
Dittemore said the engineering data showed a rise of 20 to 30 degrees in the left wheel well about seven minutes before communication was lost with the spacecraft. Then there was a rise of about 60 degrees over five minutes in the lefthand side of the fuselage above the wing, he said.
On the right side, the shuttle temperature rose the normal 15 degrees over the same period, he said. All the readings came from sensors underneath the thermal tiles, on the aluminum hull of the craft. The temperature rises were followed by increased drag on the spacecraft that caused its automated flight system to adjust its path, he said. The adjustments were large enough that ''we have never seen it to this degree,'' but still were within the shuttle's capabilities, he said.
Communication with the shuttle was lost soon after. ''It was if someone had cut the wire,'' Dittemore said.
The left side of the spacecraft has been the focus of suspicion almost from the start. Investigators are focusing on whether a broken-off piece of foam insulation from the big external fuel tank caused damage to the shuttle's left wing during liftoff Jan. 16 that ultimately doomed the flight 16 days later.
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.
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