Skip to comments.Shuttle Investigators Zero in on Breach
Posted on 04/29/2003 7:20:26 PM PDT by NormsRevenge
Shuttle Investigators Zero in on Breach
HOUSTON - Columbia accident investigators said Tuesday they are close to zeroing in on where a hole opened up in the spaceship's left wing and strongly suspect the fatal blow was caused by a chunk of flyaway foam at liftoff.
"I feel that we're probably within 30 inches of where the actual breach occurred," said Roger Tetrault, a member of the Columbia Accident Investigation Board. "We're closing in."
A fragment of a panel or seal along the vulnerable leading edge of Columbia's left wing is almost certainly what was missing when Columbia descended through the atmosphere three months ago this week, the board said. This missing mystery object floated away two days into the doomed flight, unnoticed by the crew or ground controllers.
Tetrault said he and colleagues have narrowed down the location of the deadly breach to either the lower half of a reinforced-carbon panel or a section of one of the carbon seals on either side, just a little more inboard than previously thought. All the data and debris seem to support this position on the underside of the wing, and further analysis should pinpoint it further, he said.
The top portion of the panel in question and possibly part of the two seals as well have been found and show extreme heat damage. In addition, X-rays have uncovered small drops of molten metal sprayed uniformly on the back of the same panel fragment, making this a likely area for the breach, Tetrault said. The sequence of failing sensors and burning wires during Columbia's descent also points to this area.
The gap created by the broken panel or seal let in the scorching gases of atmospheric re-entry and led to the shuttle's breakup over Texas on Feb. 1. All seven astronauts were killed.
"My hope is that we'll be able to get to the bottom of this and be able to say, with some precision, where the hole is and what size the hole is," said Tetrault, a retired corporate executive who worked with nuclear submarines.
Tetrault said the hole was at least 100 square inches, and "the weight of the evidence right now is fairly solid" it was created by a suitcase-size piece of foam insulation that ripped off Columbia's fuel tank shortly after liftoff in January. It's "highly likely" that the foam, the mystery object on flight day two and the catastrophe are all related, he said.
"If things keep progressing the way they are, I think you'll be able to say that it would be highly unlikely not to be" the foam, he added. "But I don't think there's anybody on the board who's ready to jump and say at this particular point that it is certain that the foam created the breach."
The chairman of the board, retired Navy Adm. Harold Gehman Jr., said he hopes to have a working hypothesis in the next one or two weeks, based on "mountains of data and mountains of debris."
Nearly 40 percent of Columbia has been found 78,000 pieces in all and the intensive search in Texas is wrapping up.
While much of the focus in recent weeks and months has focused on temperature, pressure and strain measurements collected during Columbia's final minutes, the board has just initiated an inquiry into similar data gathered during launch. Many of these readings come from an onboard recorder that was found on a muddy hillside 1 1/2 months after the disaster.
Gehman said none of the launch data "leaps out at you as being startling" but noted that some readings show "little squiggles" in pressure, strain and temperature variations that require more scrutiny.
"It's really premature to speculate if there's anything there," Gehman said. "We really are doing this from the point of view of not missing anything, rather than we smell a rat."
Also still hanging is a series of foam impact tests at Southwest Research Institute in San Antonio. The tests will begin this week with shuttle thermal tiles and lead up to the most critical targets real shuttle wing panels and seals in June. Chunks of foam will be hurled at these objects around 450 mph, the speed at which the launch debris is believed to have struck the edge of Columbia's left wing.
On the Net:
Columbia Accident Investigation Board: www.caib.us
Which no one ever did.
No NASA administrator rejected any potential explanation.
"We don't believe it's this chunk of foam. It's got to be something else that we don't know about yet," Mr. Dittemore said, holding high a suitcase-sized block of foam during a briefing at Johnson Space Center in Houston.
"As you focus your attention on the debris, we're focusing our attention on what we didn't see," he told reporters as he distributed the 16-by-20-by-6-inch foam blocks so they could get a feel for the size and mass of the material involved.
"Right now it just does not make sense to us that a piece of debris could be the root cause for the loss of Columbia and its crew. There's got to be another reason," Mr. Dittemore said, suggesting that the shuttle disaster was caused by "another event" that escaped detection.
That looks an awful lot like a NASA administrator trying to dismiss the foam to me. "There's got to be another reason." sounds like a man looking for another cause to me. Your milage may vary. Yes, he was slapped down and retracted this a day later, but let's not pull some Soviet-style revisionism and pretend that this never happened.
What about the 18 days it was in orbit?
What about the constant exposure to sunlight and shadow resulting temperature variations of approx. 600 degrees?
Why hasn't anyone noted in all of these articles concerning the "investigation", the orbital telemetry data?
If the insulation came off after 2 days in orbit, it should show clearly.
Temperature telemetry data should show nominal temp data in the suspected areas for the first 2 days, then, for the next 16 days, a clearly recognizable temp fluctuation.
Since I actually watched all Dittemore's press conferences, I know he specifically never ruled out ANY explanation. He didn't particularly favor the foam explanation based upon their previous understanding of its effects, but that is not the same as a rejection of it.
In reality there may be still some missing explanation of why the missing section floated loose -- a two or multi-cause event.
No one ever rejected any explanation -- they investigated all possibilites. There was no cover up, there was no duplicate key to the food locker.
The foam explanation should not be leapt on just because it seems to most obvious. It should be accepted only after it passes all rigorous causality tests. This is about scientific rigor, not about stroking your ego or blame throwing.
Wow! Do they think the foam had something to do with the accident? /sarcasm off
It will all come out. Too many people know what happened.
October 1, 2003