OUSTON, Feb. 16 — The scrambled data from the final moments of the shuttle Columbia's flight showed that two thrusters fired briefly in a last-ditch effort to regain control.Posted on 02/17/2003 1:11:36 PM PST by brityank
OUSTON, Feb. 16 — The scrambled data from the final moments of the shuttle Columbia's flight showed that two thrusters fired briefly in a last-ditch effort to regain control.
These scraps of flight information, gleaned from data received in the 32 seconds after mission control lost radio contact, suggest that the Columbia astronauts might have had time to develop a sense of the shuttle's plight. But NASA spokesmen would not speculate on the meaning of the data, which were released on Saturday by the accident investigation board led by retired Adm. Harold W. Gehman Jr.
Investigators have been searching for clues in the "mostly ragged, mostly unintelligible data" from the final 32 seconds of the flight, said Rob Navius, a NASA spokesman.
The shuttle had been fighting drag on its left wing before losing control on Feb. 1 over Texas, and NASA previously announced that two of the shuttle's jets had fired before communication was lost. Ron D. Dittemore, the shuttle program manager, said in a Feb. 5 briefing that the data from that point showed that "more and more flight control muscle is being added to keep the vehicle pointed straight ahead and eventually that flight control muscle is going to run out; you only have so much."
"And when it does, you eventually will lose control," Mr. Dittemore said. The reason for the drag is still unexplained, but the new information shows that the craft was putting still more muscle into its effort to correct its course.
The shuttle's jets are part of its reaction-control system, which is made up of 44 jets fueled by blending two chemicals that ignite upon contact with each other, nitrogen tetroxide and monomethyl hydrazine. During the shuttle's entry into the atmosphere, the craft is guided by its onboard computers, and the pilot takes over for landing.
The extra data was retrieved from a little-known form of communication on space shuttles. In addition to having communication gear that sends its signals earthward, shuttles have an antenna that points up. These signals are received by Tracking Data and Relay System Satellites, which relay signals from lower orbiting satellites, and from space shuttles, back to the Earth.
Such information comes through even when other transmissions are disrupted by re-entry.
The shuttle investigation board also said the workers sorting debris at the Kennedy Space Center had also discovered one of five general-purpose computers from Columbia. An earlier announcement of the discovery of one of the same computers, which are used to control the shuttle's functions, proved to be mistaken. The computers are not like the black box used in general aviation, and do not even have hard drives to store information. In its status report, the board said that the recovered computer had lost its battery, which keeps data alive in some chips, so "investigators held out little hope of extracting additional information."
Alan Buis, a NASA spokesman, said, "Without the battery attached, the RAM, the random access memory, would be immediately erased." Each of the computers, which are made by IBM, is 7.62 inches high, 10.2 inches wide and 19.55 inches long. Each weighs 57 pounds.
The search for other pieces of debris and the clues that they might hold is continuing. Attempts to find debris in New Mexico have been unsuccessful. The shuttle board has said that the westernmost piece of confirmed shuttle debris recovered is a tile found about 20 miles west of Fort Worth.
A main engine turbo pump was recovered near Fort Polk, La. The 800-pound pump hit the ground with such force that it was found 14 feet below the surface.
NASA said that the mission management team did not meet today and would not meet on Monday and that the Gehman commission had no formal meetings scheduled during that time. Members of the board have returned to Houston after visiting the Kennedy Space Center in Florida, the Marshall Space Flight Center in Huntsville, Ala., and the Michoud Assembly Facility near New Orleans last week.
There is no such video.
..two thrusters fired briefly in a last-ditch effort to regain control. The yaw thrusters are nomally firing at this point in the re-entry, because there is not enough air, and the shuttle is in a too high a pitch attitude to make the rudder/speedbrake functional. The thrusters are the only means of yaw control at this point.
The extra data was retrieved from a little-known form of communication on space shuttles. In addition to having communication gear that sends its signals earthward, shuttles have an antenna that points up. These signals are received by Tracking Data and Relay System Satellites, which relay signals from lower orbiting satellites, and from space shuttles, back to the Earth. Little known only to NYT reporters. And there are four S-band PM Quad antennas, and two S-Band FM hemi antennas, as well as the UHF antennas. No matter what the orientiation of the shuttle, the GPCs select which antennae should be used.
The computers are not like the black box used in general aviation, and do not even have hard drives to store information...."investigators held out little hope of extracting additional information." Obviously, this so-called reporter has not been to space camp. The main memory in the GPC's is core memory, and the "hard drives" are the Mass Memory Units which store their data on magnetic tape. Both of these are non-volatile if they survived the re-entry and didn't suffer too much heat.
Each of the computers, which are made by IBM, is 7.62 inches high, 10.2 inches wide and 19.55 inches long. Each weighs 57 pounds. Now there's some really useful information. What a jerk.
Hey; if he can't baffle you with his brilliance, at least he'll try to baffle you with his bullsh_t! LOL
If you've actually heard the last transmission from Columbia, it sounds pretty clear to me that they knew something was wrong. When they mention the tire pressure problem, the pause and uncertainty in the response, before it gets cut off, sounded to me like it came from someone who knew something was going wrong. This is similar to the Challenge accident, where you can hear the microphone get keyed and the initial pop of the explosion because their panel indicated the engines were overheating and shutting down and they were about to call down to ask what was wrong. In both cases, the crews could see that something was wrong but everything played out too quickly for them to do anything about it.
The loss of the stabilizer of course would have been all she wrote. Even as it was, if the fuselage's overall control system integrity had been maintained, with the drag forces encountered, I wonder if they were looking at a real possibility of landing far, far short of Kennedy Space Center...
One of the early lessons in our X- supersonic testing was the need for a large vertical stabilizer; larger than initially thought.
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