NASA's investigation reveals that at some point the shuttle's autopilot was disconnected; apparently, the crew members noticed the malfunction and tried to control the situation themselves; senior officials: the investigation is taking longer than planned
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Picture left: Columbia's main left tire in the remains storage hall. On the right - complete right tire
The "Columbia" began to disintegrate before the connection was severed
11/3/2003
CNN reported early this morning that NASA denies the claims that someone, apparently the astronauts, took command of the autopilot before the space shuttle Columbia disintegrated. As you may recall, we published on this website about two weeks ago that in an attempt to prevent the drift caused by the failure of the left wing , the shuttle performed four ignitions of engines intended to correct its course, two of the ignitions were In the clear of the autopilot and the cause of the other two is unknown, i.e. it is not clear whether they were also carried out by the autopilot or by the crew members.
New details from the investigation into the crash of the space shuttle "Columbia" at the beginning of February reveal that the disintegration of the shuttle's body began even before contact with it was lost. It also appears that at some point the autopilot meant to land the ferry was disconnected, apparently because the crew members realized the malfunction and tried to control the situation themselves.
Natan Gutman, Haaretz reports that in recent days, following findings from the investigation, NASA updated the chain of events in the last moments before the crash. The updated version, the 14th in number, shows that two seconds before contact with the shuttle was finally lost, it was already evident that it was in distress The data that arrived indicated that the auxiliary engines were unable to stabilize her trajectory, and that she tilted to the side at a rate of 20 degrees per second.
This means that the shuttle was actually in a spin and that it completed a complete revolution around itself every 18 seconds. The reason for the spinning was a severe impact that the shuttle suffered on its left side, which caused it to "drift" in that direction. The shuttle's control system automatically activated the right auxiliary engine to stabilize it, but due to the heavy impact it was not possible to achieve stability.
It is still unclear what hit the wing
The new information also shows that at some point, before the loss of contact, the shuttle crew members disconnected the automatic pilot mechanism, and tried to control the shuttle themselves. Normally, control is transferred to the autopilot from the moment of entering the atmosphere until the shuttle slows down to below the speed of sound, due to the difficulty of the crew to operate in the jolts and pressures caused by entering the atmosphere. The disconnection of the autopilot system apparently indicates that the astronauts realized there was a problem and tried to control the spinning shuttle themselves, although it is also possible that the system disconnected itself after failing to stabilize the flight path.
The researchers also do not rule out the possibility that the autopilot mechanism was inadvertently stopped by one of the astronauts. It turns out that the operating handle of the mechanism is placed in such a way that it was possible to turn it off by an accidental touch. The recordings of the conversations with the shuttle show that Commander Rick Husband himself turned off the mechanism by mistake, a few minutes before entering the atmosphere. He immediately noticed the problem and fixed it. NASA does not attribute importance to this incorrect shutdown of the system, but notes that this event is evidence that the autopilot mechanism may have been turned off accidentally and not on purpose.
NASA's inspection team is still far from formulating any real conclusions about the factors that led to the crash disaster, and senior officials at the agency said that the investigation is taking longer than they first estimated. The difficulty the researchers face is determining the exact factor that led to the damage to the wing, and the way in which this damage led to the disintegration of the entire shuttle .
The shuttle tires shed light on the disaster
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Tires and fragments recovered from the remains of Columbia have led NASA engineers to propose that the left tires exploded, causing a hole in the undercarriage and thus allowing extremely hot gas to enter the shuttle's left wheel area, under the left wing. This is what researchers said on Thursday 6/3/03.
Officials with the independent investigative team looking into what caused the fall of Columbia said the new findings, while very tantalizing, leave many questions open.
"We believe there is a possibility that the tires on the left side blew," said Roger Tetrault, a member of the Columbia disaster investigation team. "The tire blowout could be a catastrophic event." specified
"These tires were hanging on the brakes and they were literally pushed out," he told reporters in Houston.
On the other hand, the tires on the right side appear to be in better condition even if you compare them to airplane tires surviving an air crash.
The question of whether the explosion happened before or after Colombia began to break up remains open. Until contact with the shuttle was lost, the data transmitted from it indicated that the pressure in the tires was normal, says the chairman of the committee, retired admiral Harold Gehman.
Besides all six tires, the search teams also found other components that shed some light on the disaster, although it is clear that it was caused by a crack in the left wing, which allowed hot gas to penetrate the structure of the spacecraft. The insulation tiles were pierced with burn marks, and engraved with molten scars. The fragments on the starboard side appear thin and black and include molten aluminum that apparently dripped from the shuttle's inner frame. Tetrault says that, moreover, remains found and shuttle data show that very hot air came out of the left wheel's undercarriage.
Gehman says the team is working hard to figure out what all this night of information means. The researchers are also looking to find out where and how much gas could have moved through the wing. "We are trying to find a script that will match the temperature readings." saying.
Molten aluminum is found on the Columbia tiles
Molten aluminum was found on Columbia's insulation tiles and inside the tip area of the left wing, and this confirms the theory that the shuttle was destroyed by hot gas that penetrated and damaged one of the points on the left wing.
Roger Tetreault, a member of the team, said that he suspects that the melting happened due to the intrusion of hot gases as well as due to the enormous warming in the passage through the atmosphere.
"My best guess is that eventually, we'll find both causes," he said. "The molten aluminum looks like black soot, and it's on both the left and right sides of the spacecraft," he said.
"Many of the tiles on the left side appear to be smeared with a black layer, the likes of which we have not seen in any flight to date," Tetrolet said.
According to him, the two left tires showed evidence of unusual and extreme heating: "They were flat and their inner was torn, almost certainly they burst in the last seconds of the shuttle's flight, Tetrolet said.
In any case, the damage to the left tires may have been caused by the heat coming from the wing. This heat, in turn, could have caused the explosives used to open the landing gear to detonate in case the door jammed just before touching the ground.
"I would not speculate that maybe the explosion of the door and the falling of the passenger compartment caused the accident. It may be a result and not the cause," said Tetrolet, a retired senior manager of several companies, and with experience in nuclear submarines.
The researchers also theorized that the foam or other debris that broke off from the external fuel tank during the January 16 launch caused damage to the wing, most likely the tip area, possibly the area around the passenger compartment - and allowed heat to penetrate the wing and destroy the shuttle.
The search for remains continues, the investigative committee held a public hearing
The investigation into the loss of the space shuttle Columbia and its crew continues. On Friday, investigators continued to search for the remains of the ferry in Texas. The day before, senior officials announced that about 417 square kilometers had been scanned so far. The search for fragments is coordinated by the Federal Emergency Agency.
That same day, the Columbia disaster investigation team also met for a hearing at the University of Houston on the Clear Lake campus adjacent to the Johnson Space Center. The head of the investigation team, Harold Gehman and the other members of the team will question several people, including the director of the Johnson Space Center, Jefferson Howell and the director of the shuttle program Ron Ditmore.
In response to Gehman's request, three more researchers joined the team. Among them Nobel laureate in physics Douglas Oshroff, former astronaut Dr. Sally Reid, and director of the Space Policy Institute at George Washington University, Dr. John Logsdon.
By Wednesday, NASA had received 6,541 still images and 34 video clips of Columbia, including the entry into the atmosphere, the debris and more from the public and the media.
In the meantime, the chairman of the investigation team, Harold Gehman, said that the team will delve deeper into the question of what role NASA management and the agency's organizational culture played in the disaster. However, it is more important, at this stage, to find what exactly caused the accident. He referred to the e-mail exchanges between flight controllers and other engineers in the final days of the Columbia flight, according to which they discussed the possibility that debris from the launch caused severe damage to the left wing. They said that they were constantly dealing with "what ifs", and did not suspect any serious problem, even though some of them predicted what would happen if a crack formed.
Meanwhile, the committee's deliberations moved from the Johnson Space Center to the nearby university. The crew members sought to distance themselves from the agency, and in fact asked NASA Administrator Sean O'Keefe to remove some of the senior officials of the shuttle program from the investigation. Gehman said he was satisfied that O'Keeffe responded to the request. He refused to name the senior NASA officials whom he asked to be removed from the investigation.
