Ah, I found an oblique reference in the New York Times: "NASA engineers had already seen how fixes can break things. After they made a minor change in the foam application process in the late 1990's to comply with environmental rules, small divots of foam rained off of the tank during ascent. The phenomenon, called popcorning, was caused by trapped bubbles; NASA solved the problem by venting the foam with tiny holes, but it was a reminder, if any was needed, that seemingly small changes could have profound effects." This come from: http://nytimes.com/2005/07/31/science/space/31foam.html? hp&ex=1122782400&en=f35a8f54ae5625aa&ei=5094&partner=homepage (Access to this link may require you to register with NYTimes.com...) So it would appear that they did have a problem born of the CFC elimination, and subsequently solved. Still, I want to know more... Jim On Jul 29, 2005, at 7:43 PM, Jim Cobb:
I've been waiting for some mention of the possible role the CFC, ozone hole, scare may have played in the destruction of Columbia and NASA's subsequent problems.
You know, I never gave that any thought, the trapped bubble thing that is. An air bubble in the wrong place during an ascent could have a disastrous outcome. I was telling Patrick just yesterday, about a dive student I had at a depth of 60 feet, almost 3 atmospheres, who had an air bubble get trapped inside one of the caps on his teeth. Of course we didn't know it at the time, but as we started our ascent towards the surface we knew, because the cap blew off nearly choking him. Back to the Shuttle. If during the installation of the foam you were to somehow end up with a little pocket of trapped air that you somehow missed, and it wouldn't have to be very big, you could end up with one heck of a bubble by the time you hit space. Add to that, the heat from the ascent, and you could have chunks of foam blowing all over the place. Hmmmmm... That makes perfect sense. Quoting James Cobb <james@cobb.name>:
Ah,
I found an oblique reference in the New York Times:
"NASA engineers had already seen how fixes can break things. After they made a minor change in the foam application process in the late 1990's to comply with environmental rules, small divots of foam rained off of the tank during ascent. The phenomenon, called popcorning, was caused by trapped bubbles; NASA solved the problem by venting the foam with tiny holes, but it was a reminder, if any was needed, that seemingly small changes could have profound effects."
This come from:
http://nytimes.com/2005/07/31/science/space/31foam.html? hp&ex=1122782400&en=f35a8f54ae5625aa&ei=5094&partner=homepage
(Access to this link may require you to register with NYTimes.com...)
So it would appear that they did have a problem born of the CFC elimination, and subsequently solved. Still, I want to know more...
Jim
On Jul 29, 2005, at 7:43 PM, Jim Cobb:
I've been waiting for some mention of the possible role the CFC, ozone hole, scare may have played in the destruction of Columbia and NASA's subsequent problems.
Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://www.utahastronomy.com
That's why they call it "pop-corning" --- diveboss@xmission.com wrote:
you could have chunks of foam blowing all over the place. Hmmmmm... That makes perfect sense.
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A quick calculation tells me that when the "item that Chuck mentioned" experiences "the trapped bubble thing" effect, it will have grown to the size of Panama. Bob Grant ----- Original Message ----- From: <diveboss@xmission.com> To: <utah-astronomy@mailman.xmission.com> Sent: Saturday, July 30, 2005 3:48 PM Subject: Re: [Utah-astronomy] Re: That debbil foam again
You know, I never gave that any thought, the trapped bubble thing that is. An air bubble in the wrong place during an ascent could have a disastrous outcome.
I was telling Patrick just yesterday, about a dive student I had at a depth of 60 feet, almost 3 atmospheres, who had an air bubble get trapped inside one of the caps on his teeth. Of course we didn't know it at the time, but as we started our ascent towards the surface we knew, because the cap blew off nearly choking him.
Back to the Shuttle. If during the installation of the foam you were to somehow end up with a little pocket of trapped air that you somehow missed, and it wouldn't have to be very big, you could end up with one heck of a bubble by the time you hit space. Add to that, the heat from the ascent, and you could have chunks of foam blowing all over the place. Hmmmmm... That makes perfect sense.
Quoting James Cobb <james@cobb.name>:
Ah,
I found an oblique reference in the New York Times:
"NASA engineers had already seen how fixes can break things. After they made a minor change in the foam application process in the late 1990's to comply with environmental rules, small divots of foam rained off of the tank during ascent. The phenomenon, called popcorning, was caused by trapped bubbles; NASA solved the problem by venting the foam with tiny holes, but it was a reminder, if any was needed, that seemingly small changes could have profound effects."
This come from:
http://nytimes.com/2005/07/31/science/space/31foam.html? hp&ex=1122782400&en=f35a8f54ae5625aa&ei=5094&partner=homepage
(Access to this link may require you to register with NYTimes.com...)
So it would appear that they did have a problem born of the CFC elimination, and subsequently solved. Still, I want to know more...
Jim
On Jul 29, 2005, at 7:43 PM, Jim Cobb:
I've been waiting for some mention of the possible role the CFC, ozone hole, scare may have played in the destruction of Columbia and NASA's subsequent problems.
Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://www.utahastronomy.com
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participants (4)
-
Chuck Hards -
diveboss＠xmission.com -
James Cobb -
Marilyn Smith