Posted on 02/04/2003 4:32:49 AM PST by MeekOneGOP
Searching for answers
NASA says it may have taken liftoff damage too lightly
02/04/2003
HOUSTON - Space agency officials said Monday that they might have underestimated the damage caused to shuttle Columbia when debris fell from the external tank shortly after launch and struck the left wing.
"We're completely redoing the analysis from scratch. ... We want to know if we made any mistakes," said Ron Dittemore, shuttle program director.
The piece of insulation that fell off the shuttle's giant external tank 81 seconds after launch is estimated to have been 20 inches by 16 inches by 6 inches and to have weighed nearly 3 pounds, Mr. Dittemore said. The shuttle was traveling at more than 1,600 mph when the debris was shed.
Study of possible impact scenarios led to two estimates of the worst-case result: loss of a single tile near the left landing gear door and partial loss of a number of tiles in an area 32 inches by 7 inches by 2 inches, he said.
"In both those cases, the analysis predicted that even though you might have localized structural damage, you would not have damage sufficient to cause a catastrophic event nor impact the flying qualities of the vehicle," Mr. Dittemore said.
But he said NASA was having second thoughts about the debris it had deemed "inconsequential."
In looking again at the earlier debris investigation and reviewing data sent down by Columbia, engineers are beginning to understand more about the debris that struck the left wing on launch and about heat spikes on the left side before the ship disintegrated Saturday, killing seven astronauts.
"We have pieces of information, but I think it's around the edges," Mr. Dittemore said. "We may never know the exact root cause ... but we're going to do our darnedest to find it and fix it."
He said that, since the disaster, he has become aware that some people inside NASA thought the Columbia's situation was graver than the mission's engineering team had judged. But he said no one approached him while the craft was in space to voice any fears or question the consensus that the crew was safe.
"There have been some reservations expressed by individuals" in recent days, he said. "They didn't surface; they didn't come forward at the time."
Search moves westward
MICHAEL MULVEY / DMN Volunteers prepare to comb a forest near Hemphill, Texas, for debris and remains. An astronaut's remains were found there over the weekend. |
Mr. Dittemore said the search for debris has been extended westward, even as far as California, where the first problems were seen in data from the ship.
If Columbia did begin losing thermal tiles over California, as at least one observer has suggested, and if NASA can recover those tiles, the numbers on the tiles will pinpoint the site of the initial failure, he said.
"If we can find ... any tile or structure upstream of Fort Worth, if that exists, that is extremely important to us," he said. "I'm hopeful that in the areas [of the shuttle] we're most interested in, we'll find enough debris to reconstruct it."
Something clearly was affecting the shuttle's "flying qualities" as it streaked toward Florida. Over the course of the craft's final two or three minutes, the computers issued a series of commands to different systems to correct the shuttle's attempts to roll to the left, Mr. Dittemore said.
First, the computers adjusted the elevons, movable panels on the rear edges of the wings. Then, thrusters fired to force the shuttle's nose to the right.
The maneuvers presumably were necessary because damage to Columbia's heat shield or other surfaces altered the craft's shape and its aerodynamic behavior.
"We were losing ground," Mr. Dittemore said.
No easy answers
All the clues gathered so far - hot spots in the left wheel well and on the left fuselage, loss of sensors on the wing, in the wheel well and elsewhere, increasing aerodynamic instability - are tantalizing but fail to add up to a probable cause, Mr. Dittemore said.
For instance, the temperature in the wheel well, where the first trouble signs occurred, rose 30 to 40 degrees over five minutes. That's enough to say something was haywire, but - given that the external temperature was 2,000 degrees Fahrenheit - hardly enough to indicate that the heat shield had failed, Mr. Dittemore said.
"It's telling us something. We're just trying to figure out what it's telling us," he said.
| COLUMBIA TIMELINE | |
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Debris strike
The agency also released more details about when and how mission managers and engineers analyzed the impact of the debris strike at launch.
The incident was first noticed Jan. 17, a day after launch, when video was reviewed. It was discussed in seven more meetings through Jan. 27. In each case, the finding was that the debris' impact would not threaten the safety of the vehicle or the crew, Mr. Dittemore said.
Daily mission reports, released by NASA, supported Mr. Dittemore's account.
Mr. Dittemore was asked whether, if managers had learned the extent and location of the damage - for instance, by using satellite cameras to photograph the shuttle in flight - they might have adjusted Columbia's position during re-entry so that the undamaged right wing could take the brunt of the heat.
Mr. Dittemore said that though such a procedure is theoretically possible, NASA has never developed one. In any case, he said, changing the shuttle's position during re-entry would have altered its course, and it would have come to Earth somewhere other than the landing strip at Cape Canaveral, Fla.
"We would have had to sacrifice the vehicle," he said. "You'd have to get to a certain altitude and ask the crew to bail out."
| MEMORIAL SERVICE | |
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President Bush, who met Monday with NASA Administrator Sean O'Keefe at the White House, will attend the service.
Ex-president visits
On Monday, the president's father and mother, former President George Bush and his wife, Barbara, visited the space center, where they spoke first to the team investigating Columbia's demise and then to the crew of the International Space Station.
"We just came by to wish you well and tell you that, having talked to our son as late as this morning, he expresses full confidence in the NASA program and certainly his best wishes go to you," Mr. Bush told station commander Kenneth Bowersox.
"We're all doing fine up here," Mr. Bowersox said. " We're sad at the loss of our friends, but we're also concerned about all of you on the ground, the way you're reacting.
"We know that everyone down there shares a lot of pain."
Tuesday's memorial service at an open-air quadrangle will not be open to the public. The 11:45 a.m. ceremony will be restricted to NASA employees and other people directly connected to the space program.
"It's just going to be our family here," said space agency spokeswoman Eileen Hawley.
A similar service for the crew of the shuttle Challenger 17 years ago drew an estimated 14,000 people, and officials said they expect a similar number to attend Tuesday's event.
Staff writer Victoria Loe Hicks in Dallas contributed to this report.
E-mail bnichols@dallasnews.com
Very close-up, slo-mo of the Columbia launch debris
Video link: Shuttle over D/FW, Texas
I wonder how many engineers were still around from that first flight some 20 years ago.
If NASA is like most places, they probably managed to run off, "rightsize", or force into early retirement most of the engineers that were around during the first flight.
It's quite likely that the only people still around from 20 years ago were dead-wood political appointees and management beancounters.
Of course, those parasites will likely wind up creating even more layers of pointy-haired management for themselves after the recent tragedy.
Engineers? We don't need no stinkin' engineers.... Why pay an engineer to sit around running complex computer simulations all day when all you need is a gold-plated powerpoint presentation and the latest version of Excel?
Naw... really..!!! I'm shocked.
Video shows shuttle may have shed debris over Arizona -
check out this video taken by amateurs
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