MMMMmmmm! Tile repair goo!
Posted on 07/30/2005 1:46:44 PM PDT by NormsRevenge
HOUSTON SPACE CENTER, Texas - Two spacewalking astronauts armed with caulking guns, putty knives and foam brushes practiced fixing deliberately damaged shuttle heat shields Saturday, a job they hope they won't have to do for real.
Although Discovery suffered some scrapes and chips during liftoff, none of the damage appears to warrant orbital repairs, space agency officials said.
As the two astronauts completed the mission's first spacewalk, NASA was on the verge of extending Discovery's visit at the international space station. With future shuttle flights grounded because of Discovery's fuel-tank foam loss during liftoff, the space agency would like to keep the crew there an extra day to haul over surplus supplies and chip in with some station maintenance.
In a pair of tests designed in the wake of the 2003 Columbia tragedy, astronauts Soichi Noguchi and Stephen Robinson worked on custom-made samples of thermal tile and panels that were cracked and gouged before flight. They squeezed and dabbed dark goo into the crevices as they sped around the planet.
The sticky material got on their gloves and clumped to the ends of their putty knives. But spacewalk managers had feared a much bigger mess and were pleased with the relative neatness of it all.
"It's about like pizza dough, like licorice-flavored pizza dough," Robinson said as the near-black filler material oozed from his high-tech caulking gun. He used a putty knife to smooth down the substance, again and again.
"The cleaner it is, the better work you do, just like anything," Robinson said, holding out his knife for Noguchi to wipe.
The astronauts reported some bubbling in the two repair materials — a paintlike substance for the thermal tiles that cover most of a shuttle, and a thick paste for the reinforced carbon panels that line the wings and nose cap. The paste swelled up in the cracks like rising dough and, as the experiment wore on, was harder to get to stick because of colder than desired temperatures outside.
It was all valuable feedback; engineers wanted to see how their creations fared in the weightlessness of space for possible future use in an emergency. Neither the bubbling nor swelling was surprising, said Cindy Begley, the lead spacewalk officer.
Columbia's astronauts had no such tools or techniques at their disposal. Of course, neither they nor flight controllers knew Columbia had a gaping hole in the left wing, left there by a 1.67-pound chunk of fuel-tank foam insulation that broke loose at launch.
A piece of foam just over half that size came off Discovery's external fuel tank during last week's liftoff. It missed Discovery, but was enough to ground all future shuttle flights. A smaller foam fragment may have struck the right wing, but lasers and other sensors found no evidence of damage.
None of the repair kits flying on Discovery could mend a hole the size of the one responsible for Columbia's catastrophic re-entry, estimated between 6 and 10 inches across. It could be years before engineers come up with such a big patch. For now, the largest hole that any of the repair methods aboard Discovery could tackle would be 4 inches.
The astronauts will test a third repair technique, essentially a plug, inside Discovery later this week.
Once the repaired samples are back on Earth, engineers will analyze them to see how deep and how well the filler material penetrated. None will be torched, however, to simulate the searing heat of re-entry. The spacewalkers had to skip the one sample intended for laboratory test-firing because they ran out of time.
In the first of three spacewalks planned for this mission, Noguchi and Robinson also made some long-overdue space station repairs. They restored power to a gyroscope that stopped working four months ago and replaced a broken Global Positioning System antenna.
"Great job. Everything was just perfect. Extra stuff got done," Mission Control radioed as the seven-hour spacewalk came to a close. "You guys get some rest."
As soon as Robinson and Noguchi were back inside, their shuttle crewmates pulled out their 100-foot, laser-tipped inspection crane to survey Discovery's left wing one more time. Engineers wanted to make sure they didn't miss any signs of damage.
On Sunday, NASA expects to wrap up all its analysis of Discovery's thermal shielding and give the final safety clearance for the shuttle's descent in another week.
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On the Net:
NASA: http://www.nasa.gov/returntoflight/main/index.html
Bondo! Fill those holes and smooth it out. Slap on some paint and it's ready for sale.
That's not saying much for NASA. After the fuel gauge problem, I was expecting something else to go wrong. The shuttle is OLD. Way past its prime. I'm just glad the astronauts made it up there alive. Now let's hope they make it back alive.
You think the people at Nasa knew before watching the video from the tank camera that the foam would fall off?
It's happened before. The foam is an ongoing problem. They knew there was a strong possibility (or probability) that a chunk of foam would fall off and hit the shuttle. Yet they let the shuttle go up anyway. NASA said it was a "test flight". Why were they gambling with peoples' lives? The astronauts, you may have read, were disappointed (probably an understatement) to hear that the foam problem was still an issue. Did NASA just forget about the foam problem, or did they assure the astronauts that the problem didn't exist anymore? Either way, it was a bad decision to send up an aging shuttle with known problems. I can't imagine the stress of the astronauts on the return flight.
"It's about like pizza dough, like licorice-flavored pizza dough"..
What? He did he taste some?
Wonder how many $ this little science experiment cost me?
A complete overhaul of NASA is in order - with new people in decision-making capacities.
I don't agree at all. Space is never going going to be safe! It is a dangerous enterprise, let's face it and live with it. We have turned into a nation of cowards.
Over 20,000 people died making the Panama Canal. 4,900 died taking the beach on Normany. Over 620,000 people died in the Civil war. 112 men died during the construction of Hoover Dam.
Hell, we lose a couple brave souls taking a risk they knew in advance and we halt the space program for years and years... Thoughout history every human accomplishment and endeavor costs lives. The human we must never lose sight for "No greatness occurs without great risk."
Electrons are electrically neutral.
No, electrons have a negative charge. But you are right about like charges repelling.
I would think a stream of positrons interacting with electrons would cause a very energetic reaction as the pairs destroy each other. I don't believe they would just pass through normal matter as you are suggesting.
Once the repaired samples are back on Earth, engineers will analyze them to see how deep and how well the filler material penetrated.
None will be torched, however, to simulate the searing heat of re-entry. The spacewalkers had to skip the one sample intended for laboratory test-firing because they ran out of time.
YOu would have thought that one would have been FIRST on the list!
Repairing Space Shuttle Tiles - make that 1002 uses.
Not the twin screw seowulf?
On the other hand, "If you can't be handsome, you might as well be handy."
Quando Omni Flunkus Moritati.
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