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Ned Potter is the science correspondent for ABC's "World News with Charles Gibson." He has reported on such topics as space exploration, the human genome and climate change.
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Shuttle Damage More Serious Than First Thought
August 12, 2007 9:16 PM
It turns out, says NASA, that the three-inch ding in Endeavour's underside is deep enough to go through the thermal tiles to the aluminum skin of the orbiter itself. It is hardly doom for the mission, or for the shuttle program overall, but it's an extra bit of trouble for both.
You can click on the picture to enlarge. For perspective, this spot is near the door for the shuttle's right-side landing gear. The tiles are six inches on a side.
The shuttle crew spent several hours on Sunday afternoon looking over the tiles with a laser rangefinder on a boom attached to the shuttle's robotic arm. Until they'd done that, they had no sense of the depth of the damage they'd spotted on Friday afternoon as the shuttle docked with the space station. (See previous post HERE.)
John Shannon, who heads the Mission Management Team for shuttle flights, says they were prepared for this. "We have spent a lot of money in the program and a lot of time and a lot of people's efforts to be ready to handle exactly this case."
More from NASA is HERE. It's worth noting that their headline Sunday night was, "Managers Add Three Days to Shuttle Mission." Endeavour is drawing power from the space station's solar panels instead of its own fuel cells for the first time, so it can stay longer.
Which gives managers more time to decide whether to send spacewalkers out to go repair the hole; since the Columbia accident in 2003, they've devised various ways of covering it with sealant, or screwing a protective plate over it.
They have to decide if astronauts, in their clumsy suits, run a risk of doing more harm than good, though. The hole is not in as sensitive a place as the one that's believed to have led to Columbia's destruction.
But there will probably be a new round of talk about whether shuttles ought to be launching with the built-in weaknesses that come from having a big fuel tank, full of super cold liquid hydrogen and liquid oxygen, that sheds foam or ice on ascent. (There's a lot of background detail HERE.) The bracket from which the suspect foam came this time is one that NASA knew was a known problem; a redesigned version won't be ready until next year.
This flight is designated STS-118. They want to get to STS-133, give or take a few flights, then move on.
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(Note, added Monday afternoon: I've changed the headline of this post. It had used the word "hole" to describe whatever it is on Endeavour's underside, but that seemed to set off a bit of a semantic debate. John Shannon at NASA has used the word "divot.")
August 12, 2007 | Permalink | User Comments (6)
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I had the personal fortune of being able to work on the application of thspace tiles in 1970-71 at Lockheed Missile and Space company. Let me tell you this is no easy job, at the time we were experimenting on how to fasten the tiles by riveting. It is tantamont to punch a rivet thru a china cup. I wish them God Speed and take it slow to come up with the best solution.
Posted by: LT.COLR.T.CWIKOWSKI | Aug 12, 2007 9:57:17 PM
"How can a "hole" be one inch deep?"
If I take a shovel and dig a 1 foot hole in the dirt, I have a 1 foot deep hole. In this case, the foam dug one 1 inch deep into the tiles. The word "hole" doesn't have to imply it went all the way through.
Perhaps you need to think about things a little more before rejecting them out of hand. It might make reading this stuff (as well as the global warming data) more enlightening.
Posted by: Sam | Aug 13, 2007 12:04:03 AM
Why is it that the bracket redesign has taken so long, especially since it was a known problem? I'd think that, given the chances for damage, the redesign of the bracket would have been a higher priority.
Posted by: chuck | Aug 13, 2007 8:22:50 AM
In response to Sam, When shot by a bullet, is it a bullet "hole" or a "dent" is the bullet doesn't pass all the way through you regardless if it went 1cm in or 12"
Posted by: CHuck | Aug 13, 2007 1:59:36 PM
It's all too late now but to bad they couldn't have just faced the vulnerable underside away from the fuel tanks as opposed to against them.
Posted by: neil | Aug 13, 2007 6:56:29 PM
"Why is it that the bracket redesign has taken so long, especially since it was a known problem? I'd think that, given the chances for damage, the redesign of the bracket would have been a higher priority."
NASA also knew there was an O-ring issue due to temperature which in effect caused the Challenger disaster. In the end the space program is extremely complex and in most cases what they are doing has never been done before or at least few times before. Even flying the shuttle is not a common experience in the same way flying a plane or driving a car is. In the end NASA has to compromise on safety and risk in order to get anything done. Most of the time they do this without any problems, but sometimes the danger is not well understood or is not brought to attention in time and that is in effect what has happened with all major disasters for NASA, they don’t take unnecessary risks.
Posted by: Hello Moto | Aug 14, 2007 5:35:03 PM
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