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Post by ponytail61 on Jan 25, 2017 7:04:23 GMT
You would not need to get the foam up to 18,000 mph as it was a part of the shuttle and was traveling at the same speed until it broke loose. The foam then decelerated but didn't instantly reach a speed of 0 mph. The experiment was done and with some digging around you may be able to find out what speed they shot the foam at. "Hubbard played an instrumental role in spotlighting the cause of Columbia's demise. To do so, he relied on computational modeling, reinforced by experimental testing with a large compressed-gas gun done by Southwest Research Institute (SwRI) scientists and engineers in San Antonio, Texas. During the tests, scientists fired a piece of foam at a target at speeds comparable to what a falling piece of debris from the shuttle would have experienced. Researchers then observed the damage." www.space.com/19605-columbia-shuttle-disaster-mystery-object.htmlHere is the lab and I am assuming gun they used. It states that the projectile can reach 2000 fps + (about 1,400 mph) www.swri.org/4org/d18/engdyn/impact/
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Post by rmc on Jan 25, 2017 12:39:51 GMT
You would not need to get the foam up to 18,000 mph as it was a part of the shuttle and was traveling at the same speed until it broke loose. The foam then decelerated but didn't instantly reach a speed of 0 mph. The experiment was done and with some digging around you may be able to find out what speed they shot the foam at. "Hubbard played an instrumental role in spotlighting the cause of Columbia's demise. To do so, he relied on computational modeling, reinforced by experimental testing with a large compressed-gas gun done by Southwest Research Institute (SwRI) scientists and engineers in San Antonio, Texas. During the tests, scientists fired a piece of foam at a target at speeds comparable to what a falling piece of debris from the shuttle would have experienced. Researchers then observed the damage." www.space.com/19605-columbia-shuttle-disaster-mystery-object.htmlHere is the lab and I am assuming gun they used. It states that the projectile can reach 2000 fps + (about 1,400 mph) www.swri.org/4org/d18/engdyn/impact/We're trying to find an airspeed that tears away the foam from the skin of the fuel tank. (Airspeed and correct air density too... Too dense an air density, you get it torn away, but may not properly replicate conditions at altitude) I think what you're describing is focused more on propelling the foam into the skin or tiles of the shuttle. The mention of using a cannon was more about just propelling air to the airspeed of the shuttle at 80 seconds after launch, which is only 1,600 mph and not 18,000 mph. (was saying 18,000 feet in altitude though) EDIT: Probably an 'easy' test involves some sort of curved surface with the foam on it, blasted with cannon air. Doing this several times but increasing the velocity of the cannon air each time until the foam just begins to rip off. That way a speed is calibrated for where we'd expect to see foam rip away. Then do it again with a fresh foam-covered curved surface (airfoil shape, perhaps?) to confirm that this speed is the one that first starts ripping foam off of an unpainted surface. Then do it all over again with the same shape, foam-covered BUT PAINTED. And, if the foam resists tearing away with paint, then perhaps having painted the external fuel tank (as was originally designed) could have prevented the foam from ripping away the way it did back in 2003. (The stated 'myth' being a painted fuel tank could have prevented the 2003 Columbia tragedy)
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Post by the light works on Jan 25, 2017 14:04:40 GMT
You would not need to get the foam up to 18,000 mph as it was a part of the shuttle and was traveling at the same speed until it broke loose. The foam then decelerated but didn't instantly reach a speed of 0 mph. The experiment was done and with some digging around you may be able to find out what speed they shot the foam at. "Hubbard played an instrumental role in spotlighting the cause of Columbia's demise. To do so, he relied on computational modeling, reinforced by experimental testing with a large compressed-gas gun done by Southwest Research Institute (SwRI) scientists and engineers in San Antonio, Texas. During the tests, scientists fired a piece of foam at a target at speeds comparable to what a falling piece of debris from the shuttle would have experienced. Researchers then observed the damage." www.space.com/19605-columbia-shuttle-disaster-mystery-object.htmlHere is the lab and I am assuming gun they used. It states that the projectile can reach 2000 fps + (about 1,400 mph) www.swri.org/4org/d18/engdyn/impact/We're trying to find an airspeed that tears away the foam from the skin of the fuel tank. (Airspeed and correct air density too... Too dense an air density, you get it torn away, but may not properly replicate conditions at altitude) I think what you're describing is focused more on propelling the foam into the skin or tiles of the shuttle. The mention of using a cannon was more about just propelling air to the airspeed of the shuttle at 80 seconds after launch, which is only 1,600 mph and not 18,000 mph. (was saying 18,000 feet in altitude though) EDIT: Probably an 'easy' test involves some sort of curved surface with the foam on it, blasted with cannon air. Doing this several times but increasing the velocity of the cannon air each time until the foam just begins to rip off. That way a speed is calibrated for where we'd expect to see foam rip away. Then do it again with a fresh foam-covered curved surface (airfoil shape, perhaps?) to confirm that this speed is the one that first starts ripping foam off of an unpainted surface. Then do it all over again with the same shape, foam-covered BUT PAINTED. And, if the foam resists tearing away with paint, then perhaps having painted the external fuel tank (as was originally designed) could have prevented the foam from ripping away the way it did back in 2003. (The stated 'myth' being a painted fuel tank could have prevented the 2003 Columbia tragedy) since we are taking it as given that the foam ripped off; i would be satisfied with first determining an air blast that ripped foam off, and then testing it properly painted with a representative paint coating.
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Post by rmc on Jan 25, 2017 15:57:21 GMT
"An air blast that ripped foam off"
An air blast on Mars capable of ripping foam off would be a different air blast on Earth.
Naturally, I mention these two worlds to pound home the point that air flow of different air density packs very, very different power to do work. I.e, all the wind on Mars simulations we discussed a while back. So if we lock down air (the air here at ground level) and insist that it must be moving at 1,600 mph (the relative air speed defined) then we are sort of mixing apples with oranges, if you see my meaning. Because the 1,600 mph air flow at altitude back in 2003 was probably at about 7 psi instead of 15 psi as it would be at ground level. And with a cannon (even if starting in a vacuum) adds air pressures where a simple air stream wouldn't as much (the air stream at altitude)
So, if we instead focus on the amount of work necessary to just begin to tear the foam away, we create a venue that isn't so critically focused on fluid flow specifics and is instead looking for the situation that survives what would otherwise crumble away.
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Post by the light works on Jan 25, 2017 16:14:20 GMT
"An air blast that ripped foam off" An air blast on Mars capable of ripping foam off would be a different air blast on Earth. Naturally, I mention these two worlds to pound home the point that air flow of different air density packs very, very different power to do work. I.e, all the wind on Mars simulations we discussed a while back. So if we lock down air (the air here at ground level) and insist that it must be moving at 1,600 mph (the relative air speed defined) then we are sort of mixing apples with oranges, if you see my meaning. Because the 1,600 mph air flow at altitude back in 2003 was probably at about 7 psi instead of 15 psi as it would be at ground level. And with a cannon (even if starting in a vacuum) adds air pressures where a simple air stream wouldn't as much (the air stream at altitude) So, if we instead focus on the amount of work necessary to just begin to tear the foam away, we create a venue that isn't so critically focused on fluid flow specifics and is instead looking for the situation that survives what would otherwise crumble away. that's what I said.
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Post by rmc on Jan 25, 2017 21:43:57 GMT
"An air blast that ripped foamssß off" An air blast on Mars capable of ripping foam off would be a different air blast on Earth. Naturally, I mention these two worlds to pound home the point that air flow of different air density packs very, very different power to do work. I.e, all the wind on Mars simulations we discussed a while back. So if we lock down air (the air here at ground level) and insist that it must be moving at 1,600 mph (the relative air speed defined) then we are sort of mixing apples with oranges, if you see my meaning. Because the 1,600 mph air flow at altitude back in 2003 was probably at about 7 psi instead of 15 psi as it would be at ground level. And with a cannon (even if starting in a vacuum) adds air pressures where a simple air stream wouldn't as much (the air stream at altitude) So, if we instead focus on the amount of work necessary to just begin to tear the foam away, we create a venue that isn't so critically focused on fluid flow specifics and is instead looking for the situation that survives what would otherwise crumble away. that's what I said. Oops! Misread something you wrote apparently! Sorry! I suppose I assume I am not clearly explaining what it is I am getting at and then further assume I need to restate it... Or something like that.
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Post by the light works on Jan 26, 2017 0:19:34 GMT
Oops! Misread something you wrote apparently! Sorry! I suppose I assume I am not clearly explaining what it is I am getting at and then further assume I need to restate it... Or something like that. since we're trying to determine whether a change in material will change the results, we don't need to prove that the normal conditions will cause the undesired result - we just need to find what conditions will replicate the result - and go from there.
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Post by silverdragon on Jan 26, 2017 8:05:47 GMT
Dealing directly with that... Bed-Liner. I wonder how safe it would have been with THAT on it?..
And then again, the wing fuel tanks on Concord, would they have survived the tyre damage if the underside of the wing had a coat of Bed-liner on them?..
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Post by silverdragon on Jan 26, 2017 8:07:13 GMT
Back to suspected airborne damage what about a bird-strike?.. how would that have changed things?..
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Post by the light works on Jan 26, 2017 15:26:53 GMT
Dealing directly with that... Bed-Liner. I wonder how safe it would have been with THAT on it?.. And then again, the wing fuel tanks on Concord, would they have survived the tyre damage if the underside of the wing had a coat of Bed-liner on them?.. I suspect the paint was something along those lines.
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Post by rmc on Oct 30, 2020 23:50:21 GMT
For what it's worth, Curious Droid does mention that some have said that the lack of paint on the big orange foam fuel tank could have been a factor... about 6:00 minutes in.
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Post by the light works on Oct 30, 2020 23:57:54 GMT
For what it's worth, Curious Droid does mention that some have said that the lack of paint on the big orange foam fuel tank could have been a factor... good catch.
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Post by GTCGreg on Oct 31, 2020 3:02:50 GMT
Impressive commercial.
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Post by rmc on Oct 31, 2020 11:52:25 GMT
Yeah, most of my favorite YouTube channels use Brilliant as a sponsor now. As a result they end up pitching them like their whole video is building up to the commercial message. But, if you find earlier videos from years ago, they have basically the same sort of content or topics, but without glossing on lyrically about Brilliant at the end. Today, the segway into the sponsorship portion does make the whole thing sound like a commercial since both the sponsor and the host are interested in knowledge in some way.
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Post by wvengineer on Nov 3, 2020 12:44:11 GMT
I watched a documentary about the Challenger disaster a few weeks ago. (Challenger: The Final Flight on NetFlix) One of the things the go over is that foam damage happened from teh very start. The first launch of Columbia in 1981, with a painted tank actually had rather significant foam damage, but it was in a non-critical area.
I'll have to see if I can find info about it.
1. Foam was a problem from the start. 2. While paint may help, it would not have prevented foam damage.
I would highly recommend the documentary. Very interesting look at how NASA failed to learn from the Apollo 1 accident and how NASA management killed the crew of the Challanger.
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Post by the light works on Nov 3, 2020 14:19:03 GMT
I watched a documentary about the Challenger disaster a few weeks ago. (Challenger: The Final Flight on NetFlix) One of the things the go over is that foam damage happened from teh very start. The first launch of Columbia in 1981, with a painted tank actually had rather significant foam damage, but it was in a non-critical area. I'll have to see if I can find info about it. 1. Foam was a problem from the start. 2. While paint may help, it would not have prevented foam damage. I would highly recommend the documentary. Very interesting look at how NASA failed to learn from the Apollo 1 accident and how NASA management killed the crew of the Challanger. I forget where I read it because it was back when the disaster happened, but somebody pointed out that when something is brand new, everybody is meticulously careful, and then as it goes without disaster, they become progressively more casual, until it reaches a point where the casualness results in an accident, at which point, they become meticulously careful, again. I think the same person also pointed out that people's inherent expectation of acceptable losses is higher, the more commonplace the behavior surrounding the loss is. the point being, 7 astronauts every decade is not considered an acceptable loss, but 100 people dying per day in traffic crashes in the US is acceptable.
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Post by rmc on Nov 3, 2020 17:04:14 GMT
I watched a documentary about the Challenger disaster a few weeks ago. (Challenger: The Final Flight on NetFlix) One of the things the go over is that foam damage happened from teh very start. The first launch of Columbia in 1981, with a painted tank actually had rather significant foam damage, but it was in a non-critical area. I'll have to see if I can find info about it. 1. Foam was a problem from the start. 2. While paint may help, it would not have prevented foam damage. I would highly recommend the documentary. Very interesting look at how NASA failed to learn from the Apollo 1 accident and how NASA management killed the crew of the Challanger. Yes. Everywhere I look now wherever this question is asked the answer comes back a solid "no", painting the tank with its usual latex paint would not have prevented the accident. I posted my latest reply (thereby reactivating this topic) mainly as a slight confidence builder for myself, proving that I wasn't the only person thinking along these odd sorts of lines. For a genuine solution to the problem some have suggested that a less environmentally friendly adhesive for the foam would have likely helped - more so than latex paint anyway. I thought that sounded odd because I thought the spray on foam was its own adhesive. I didn't realize there were layers of adhesive laid down first, and then the foam sprayed on. Anyway, if limited to things like adhesives, and paint to shore up the somewhat brittle foam, I still wonder if there could have been some combination of simple materials (like better adhesive and even paint too) that would have improved the situation. Like say, the strongest adhesive available regardless of environmental impact layed down first, then the spray on foam, and then, yes, a layer of paint... but instead of latex, this time make it enamel. Enamel paint compared to laytex seems more smooth and I don't know... leathery-strong? Anyway, I'm sure there's all sorts of discussion about weight penalty, but they did apparently use adhesive and paint (from what I've heard anyway) so switching to something with a bigger weight penalty seems an okay trade off just so long as it actually helps the foam withstand the cryo expansion, flexing, vibration and torrents of wind.
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Post by wvengineer on Nov 4, 2020 0:18:32 GMT
It sound like the foam suffered from the same engineered by Committee/Politics that plagued the whole shuttle program from the very beginning and turned what could have been an efficient space hauler into an over-engineered monstrosity that could never hope to live up to performance expectations.
When environmental impact takes prescience over performance, you know that somewhere priorities are off.
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Post by the light works on Nov 4, 2020 1:44:00 GMT
wrap it with glass fiber and spray it with epoxy.
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Post by rmc on Nov 4, 2020 15:33:25 GMT
wrap it with glass fiber and spray it with epoxy. Right. Going for "foam core" essentially. That's what we're after - if it were possible. But, we're also trying to stay somewhere in the ballpark of the original, painted weight parameters. Going from latex to enamel would have an increase, but I'd bet far less than fiberglass exterior, of course.
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