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SBD
Admiral
Joined: 19 Aug 2004
Posts: 1022
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 Posted: Wed Jul 05, 2006 5:52 am Post subject: Environmentalist Caused the Space Shuttle Foam Problem? |
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Environmentalist Caused the Space Shuttle Foam Problem?
| Quote: | Laser Might Have Found Insulation Foam Flaw
By Matthew Fordahl
Associated Press Technology Writer
posted: 03:25 pm ET
21 February 2003
SAN JOSE, Calif. (AP) -- After years of concern about foam insulation breaking off and damaging space shuttle thermal tiles, NASA started evaluating -- but not widely using -- a technology that could detect subtle defects in the foam.
The process, laser shearography, was not used to check the insulation of the space shuttle Columbia's external tank before its final flight. But it has been used on other rockets as well as other parts of the shuttle, according to Laser Technology Inc., which makes the technology.
"It was under evaluation and still is,'' said John Newman, Laser Technology's chief executive. ``I'm not prepared to say why it was or wasn't used.''
On Friday, spokesmen for NASA's Marshall Space Flight Center in Alabama and Lockheed Martin Co., which builds the tanks at a plant in New Orleans, declined to comment on the new technology. The space agency has noted that any new process used on the shuttle requires lengthy testing before being implemented.
Records show NASA ordered one of the laser systems as recently as three years ago.
A 2 1/2-pound chunk of insulation that appeared to fly off and hit Columbia's heat-protecting tiles is one area of investigation into why the shuttle broke apart on its descent Feb. 1, killing all seven astronauts.
Laser shearography promised to address a concern since the earliest days of the shuttle program -- insulation peeling off and striking the tiles. Recent changes in the composition of the spray-on foam and adhesives have made it more susceptible to flaking off, experts said.
Most of the foam is applied at the Michoud Assembly Facility in New Orleans, and more is applied just before launch at Kennedy Space Center in Florida.
The spray-on foam ``has a history of debonding, sometimes striking the orbiter and causing damage,'' according to one report written in 2001 by Christopher Davis, an engineer at Kennedy Space Center. ``For this reason, shearography provides an opportunity to evaluate known areas of concern.''
Laser shearography involves vibrating the material very slightly. A laser is beamed on the surface and a digital camera records differences in the surface of the material.
In the case of foam insulation, the technology is useful in finding areas where it has ``disbonded'' from the aluminum-lithium skin of the massive external fuel tanks, Newman said.
The system can scan an area of about 32-by-36-inches every half-second, meaning the entire tank could have been tested in about 24 hours, Newman said. It can detect deformation as small as 20 nanometers. (A nanometer is about 10,000 times narrower than a human hair.)
But even this technology can't detect all possible problems, Newman said. "We can only see debonds. We can't see where the foam is weak.''
The devices, which were first introduced in 1987, start at $100,000. Besides rockets, it has been used in the testing of tires, orthopedic implants, aircraft engine parts, concrete and even golf balls, he said.
Records show NASA awarded several contracts to Norristown, Pa.-based Laser Technology since 1995, including $265,485 in 1995 and $175,600 in 2000 for laser shearograph systems and $42,933 in 1999 for repairs to the equipment.
In recent years, the flaking problem has become more common as NASA. Contractors changed the composition of the spray-on foam and adhesives to comply with health and environmental regulations, said Alfred F. Daech, a former consultant with Martin Marietta, now part of Lockheed Martin. Chromium and freon were removed.
Dirt and other foreign substances also can weaken the insulation, he said.
The problem dates back to the first shuttle launch, when Daech and others were called to the launch pad because a large bubble appeared in the external tank insulation. They were able to fix that problem without delaying the launch.
"Someone had wiped it with a rag. You could see the swirls," he said. "Improper cleaning was the culprit, usually.''
Then there was always Mother Nature to contend with. Birds would leave their droppings on the tanks at Michoud. And in 1995, at Kennedy's launch pad, a pair of woodpeckers drilled nearly 200 holes in the insulation of Discovery's tank. The spaceship had to be sent back to the hangar and each hole patched.
Newman said he hopes his company will play a role in ensuring the safety of future shuttles if in fact wayward foam turns out to be the cause of the latest disaster.
"It's something I hope makes sure this never happens again,'' he said.
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Army_(Ret)
Lt.Jg.
Joined: 06 Aug 2004
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| Posted: Wed Jul 05, 2006 10:54 am Post subject: |
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Absoulutely SBD!
http://www.newsmax.com/archives/ic/2005/7/28/93055.shtml
By the NewsMax.com Staff
For the story behind the story...
Thursday, July 28, 2005 9:27 a.m. EDT
Shuttle Foam Loss Linked to EPA Regs
As recently as last month, NASA had been warned that foam insulation on the space shuttle's external fuel tank could sheer off as it did in the 2003 Columbia disaster - a problem that has plagued space shuttle flights since NASA switched to a non-Freon-based type of foam insulation to comply with Clinton administration Environmental Protection Agency regulations.
Story Continues Below
"Despite exhaustive work and considerable progress over the past 2-1/2 years, NASA has been unable to eliminate the possibility of dangerous pieces of foam and ice from breaking off the external fuel tank and striking the shuttle at liftoff," the agency's Return-to-Flight Task Force said just last month, according to The Associated Press.
But instead of returning the much safer, politically incorrect, Freon-based foam for Discovery's launch, the space agency tinkered with the application process, changing "the way the foam was applied to reduce the size and number of air pockets," according to Newsday.
"NASA chose to stick with non-Freon-based foam insulation on the booster rockets, despite evidence that this type of foam causes up to 11 times as much damage to thermal tiles as the older, Freon-based foam," warned space expert Robert Garmong just nine months ago.
In fact, though NASA never acknowledged that its environmentally friendly, more brittle foam had anything to do with the foam sheering problem, the link had been well documented within weeks of the Columbia disaster.
In February 2003, for instance, the Philadelphia Inquirer reported:
"NASA engineers have known for at least five years that insulating foam could peel off the space shuttle's external fuel tanks and damage the vital heat-protecting tiles that the space agency says were the likely 'root cause' of Saturday's shuttle disaster."
In a 1997 report, NASA mechanical systems engineer Greg Katnik "noted that the 1997 mission, STS-87, was the first to use a new method of 'foaming' the tanks, one designed to address NASA's goal of using environmentally friendly products. The shift came as the U.S. Environmental Protection Agency was ordering many industries to phase out the use of Freon, an aerosol propellant linked to ozone depletion and global warming," the Inquirer said.
Before the environmentally friendly new insulation was used, about 40 of the spacecraft's 26,000 ceramic tiles would sustain damage in missions. However, Katnik reported that NASA engineers found 308 "hits" to Columbia after a 1997 flight.
A "massive material loss on the side of the external tank" caused much of the damage, Katnik wrote in an article in Space Team Online.
He called the damage "significant." One hundred thirty-two hits were bigger than 1 inch in diameter, and some slashes were as long as 15 inches.
"As recently as last September [2002], a retired engineering manager for Lockheed Martin, the contractor that assembles the tanks, told a conference in New Orleans that developing a new foam to meet environmental standards had 'been much more difficult than anticipated,'" the Inquirer said.
The engineer, who helped design the thermal protection system, said that switching from the Freon foam "resulted in unanticipated program impacts, such as foam loss during flight."
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GenrXr
Master Chief Petty Officer of the Navy
Joined: 05 Aug 2004
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Location: Houston
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| Posted: Wed Jul 05, 2006 6:38 pm Post subject: |
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pfft, and why in the world is anything done in New Orleans? I swear this shuttle is piece mealed from all 50 states, because every damn politician has to have their hands on a piece of it.
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Army_(Ret)
Lt.Jg.
Joined: 06 Aug 2004
Posts: 108
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| Posted: Wed Jul 05, 2006 8:17 pm Post subject: |
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Take a look at the history of it. Jake Garn and Bill Nelson both bumped back (Greg Jarvis twice, by senators) and he was killed by the Challenger diaster. Lt. Col Ellison Onizuka, I know for a fact was bumped forward by one of the senators also.
Don't even try me Gen XR. pfft.
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Army_(Ret)
Lt.Jg.
Joined: 06 Aug 2004
Posts: 108
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| Posted: Wed Jul 05, 2006 8:25 pm Post subject: |
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GenXR, I was also working art Kennedy Space Center during the Challenger, and watched it.
Pfft.
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GenrXr
Master Chief Petty Officer of the Navy
Joined: 05 Aug 2004
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Location: Houston
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| Posted: Wed Jul 05, 2006 11:31 pm Post subject: |
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| Army_(Ret) wrote: | Take a look at the history of it. Jake Garn and Bill Nelson both bumped back (Greg Jarvis twice, by senators) and he was killed by the Challenger diaster. Lt. Col Ellison Onizuka, I know for a fact was bumped forward by one of the senators also.
Don't even try me Gen XR. pfft. |
? 
My pfft was directed at the politicians who have made construction and service of the shuttle a must for their constituents. I have always been of the belief the whole damn shuttle should be serviced and built in Florida if that is where it is flying from.
For instance, the fuel tanks have O-rings because they have to be shipped in sections and assembled in Florida. If it weren't for damn politicians wanting those things built in their districts the fuel tanks would be built in one piece in Florida without O-rings, thus the challenger would still be around.
_________________
"An activist is the person who cleans up the water, not the one claiming its dirty."
"All that is necessary for evil to triumph is for good men to stand by and do nothing." Edmund Burke (1729-1797), Founder of Conservative Philosophy |
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Schadow
Vice Admiral
Joined: 30 Sep 2004
Posts: 936
Location: Huntsville, Alabama
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| Posted: Thu Jul 06, 2006 2:10 am Post subject: |
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| GenrXr wrote: | | For instance, the fuel tanks have O-rings because they have to be shipped in sections and assembled in Florida. If it weren't for damn politicians wanting those things built in their districts the fuel tanks would be built in one piece in Florida without O-rings, thus the challenger would still be around. |
Er, the O-ring catastrophe was associated with the solid rocket motors, not the tank. The tank is built in Michoud, LA and is one piece.
The solids are built in segments because no one has been able to figure out a way to cast so large a motor in one piece. Additionally, segmentation is essential in shaping the thrust-time history of the burn.
I agree that building the external tank in a humid swamp is not the brightest move NASA ever made. 
Schadow
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GenrXr
Master Chief Petty Officer of the Navy
Joined: 05 Aug 2004
Posts: 1720
Location: Houston
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| Posted: Thu Jul 06, 2006 2:53 am Post subject: |
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| Schadow wrote: | | GenrXr wrote: | | For instance, the fuel tanks have O-rings because they have to be shipped in sections and assembled in Florida. If it weren't for damn politicians wanting those things built in their districts the fuel tanks would be built in one piece in Florida without O-rings, thus the challenger would still be around. |
Er, the O-ring catastrophe was associated with the solid rocket motors, not the tank. The tank is built in Michoud, LA and is one piece.
The solids are built in segments because no one has been able to figure out a way to cast so large a motor in one piece. Additionally, segmentation is essential in shaping the thrust-time history of the burn.
I agree that building the external tank in a humid swamp is not the brightest move NASA ever made.
Schadow |
I must be recollecting old information incorrectly. Off to find that old info. 
Thanks for the heads up Schadow.
You might be wrong on this Schadow. Look at this diagram http://onlineethics.org/moral/boisjoly/rocket.html
I know not long after the second accident to columbia I read somewhere that these boosters could be built in one piece, but the company which built them in Utah was politically connected and there was no way to ship it to Florida unless done in segments.
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"An activist is the person who cleans up the water, not the one claiming its dirty."
"All that is necessary for evil to triumph is for good men to stand by and do nothing." Edmund Burke (1729-1797), Founder of Conservative Philosophy |
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Schadow
Vice Admiral
Joined: 30 Sep 2004
Posts: 936
Location: Huntsville, Alabama
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| Posted: Thu Jul 06, 2006 4:46 am Post subject: |
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| GenrXr wrote: | I must be recollecting old information incorrectly. Off to find that old info.
Thanks for the heads up Schadow.
You might be wrong on this Schadow. Look at this diagram http://onlineethics.org/moral/boisjoly/rocket.html
I know not long after the second accident to columbia I read somewhere that these boosters could be built in one piece, but the company which built them in Utah was politically connected and there was no way to ship it to Florida unless done in segments. |
The rocket motor maker, Thiokol (now ATK), was indeed politically well-connected, but all of the bidders in the original competition proposed essentially the same thing, a segmented motor, for two principal reasons: 1) Transport of a 150-ft thing weighing about 1,300,000 lb. is not feasible by air, road or rail. Even if shipped by water, getting it to the Pad 39 complex from Port Canaveral would be quite a chore and, 2) the requirement for thrust-time shaping for flight requires internal burning surface geometries that could not be achieved with removable casting mandrels.
The solids provide the great majority of total vehicle thrust from ignition to separation (about 2 minutes) and the aero loads on the vehicle at maximum ascent aerodynamic pressure (QMax) demand that the solids throttle back shortly after liftoff then throttle back up to the maximum (driven by acceptable loads on the crew and vehicle) when QMax is passed. Since there is no way to throttle a solid propellant motor, the thrust profile has to be accomplished with internal propellant shaping. The availability of the segment end surfaces, partially inhibited, provides the desired thrust tailoring.
From an industrial standpoint, it might be feasible to weld up a full-length case on the pad, install a gigantic propellant mix station, roll up ovens to cure the propellant, etc., etc., but it would still not be possible to do the internal propellant shaping to provide the desired thrust-time profile.
Before Challenger, over 1000 Titan III solid motors had flown without failure. Thiokol essentially copied the Titan O-ring sealing configuration but with serious shortcomings. I participated in a Flight Readiness Review for another launch about two years before Challenger in which an issue of O-ring erosion was discussed. An SRB recovered from a previous flight revealed a joint O-ring had been burned 50% through its cross-section. Astonishingly, the NASA managers present at the FRR said, "Hell, that gives us a 100% safety factor. Fly."
Joint O-rings should not be burned at all.
They got away with it up to Challenger.
Lemme know if you find something more on large monolithic solids. I'd definitely be interested.
Schadow
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GenrXr
Master Chief Petty Officer of the Navy
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| Posted: Thu Jul 06, 2006 1:06 pm Post subject: |
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The largest monolothic booster I could find was the Atlas 5 medium at 77 feet. I did find arguments for a monolithic replacement for the shuttles boosters, but it was at a socialist website. Maybe, I fell for some communist propoganda. btw, Schadow are you familiar with Alfred Neuman? He is a recently retired VP from Lockheed and his daughter told me the person responsible for Port Canaveral being named the launch site. During Rita, my girlfriend and I stayed at his lakehouse. I guess Lockheed had something to do with Port Canaveral and its construction way back in the day.
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"All that is necessary for evil to triumph is for good men to stand by and do nothing." Edmund Burke (1729-1797), Founder of Conservative Philosophy |
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I B Squidly
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| Posted: Thu Jul 06, 2006 2:27 pm Post subject: |
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NASA was selling a program of 20 launches a year with each shuttle carrying its own tile repair kit. Congress was cutting loose from 'Nam and didn't want any part of 'Space' either. They paid ten cents on the dollar for a work relief program too late for the Apollo workers.
The shuttle always was a red headed step-child.
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Schadow
Vice Admiral
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| Posted: Thu Jul 06, 2006 2:31 pm Post subject: |
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| GenrXr wrote: | | The largest monolothic booster I could find was the Atlas 5 medium at 77 feet. I did find arguments for a monolithic replacement for the shuttles boosters, but it was at a socialist website. Maybe, I fell for some communist propoganda. btw, Schadow are you familiar with Alfred Neuman? He is a recently retired VP from Lockheed and his daughter told me the person responsible for Port Canaveral being named the launch site. During Rita, my girlfriend and I stayed at his lakehouse. I guess Lockheed had something to do with Port Canaveral and its construction way back in the day. |
I never ran across Alfred Neuman, but the selection of Canaveral as the launch site had more to do with geography than politics. Early ground rules specified flight azimuths that would not endanger people or property on land should there be a destruct event or falling first stages of other vehicles. Eastward launches also take advantage of the earth's rotation to provide about 1000 mph kick as compared to westward launches.
Canaveral provides near-equatorial orbits limited only by Cuba in the south and the east coast of the US to the north. Vandenberg AFB on the west coast is used for southward polar orbit injection since the earth's rotation isn't a factor. That's why most of the 'black' payloads are launched from there.
Now, the location of NASA's manned flight activities (now politically corrected to 'human flight') at Johnson Space Center in Houston was a blatantly political selection. Remember LBJ?
The Atlas series of launch stages all use liquid propellant and are therefore more versatile. Relatively lightweight tankage can be erected on launch pads or in underground silos in the case of Atlas ICBMs. Also, liquid propellant rockets can easily be throttled to practically any desired thrust-time profile.
The earliest design studies for the Shuttle proposed liquid propellant first stages but there was a ground rule that the stages had to be recoverable and reused. No one could design a liquid stage that was robust enough to withstand reentry and splash in a saltwater environment. Hence, solids.
Schadow
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GenrXr
Master Chief Petty Officer of the Navy
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| Posted: Fri Jul 07, 2006 4:37 pm Post subject: |
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| Schadow wrote: | | GenrXr wrote: | | The largest monolothic booster I could find was the Atlas 5 medium at 77 feet. I did find arguments for a monolithic replacement for the shuttles boosters, but it was at a socialist website. Maybe, I fell for some communist propoganda. btw, Schadow are you familiar with Alfred Neuman? He is a recently retired VP from Lockheed and his daughter told me the person responsible for Port Canaveral being named the launch site. During Rita, my girlfriend and I stayed at his lakehouse. I guess Lockheed had something to do with Port Canaveral and its construction way back in the day. |
I never ran across Alfred Neuman, but the selection of Canaveral as the launch site had more to do with geography than politics. Early ground rules specified flight azimuths that would not endanger people or property on land should there be a destruct event or falling first stages of other vehicles. Eastward launches also take advantage of the earth's rotation to provide about 1000 mph kick as compared to westward launches.
Canaveral provides near-equatorial orbits limited only by Cuba in the south and the east coast of the US to the north. Vandenberg AFB on the west coast is used for southward polar orbit injection since the earth's rotation isn't a factor. That's why most of the 'black' payloads are launched from there.
Now, the location of NASA's manned flight activities (now politically corrected to 'human flight') at Johnson Space Center in Houston was a blatantly political selection. Remember LBJ?
The Atlas series of launch stages all use liquid propellant and are therefore more versatile. Relatively lightweight tankage can be erected on launch pads or in underground silos in the case of Atlas ICBMs. Also, liquid propellant rockets can easily be throttled to practically any desired thrust-time profile.
The earliest design studies for the Shuttle proposed liquid propellant first stages but there was a ground rule that the stages had to be recoverable and reused. No one could design a liquid stage that was robust enough to withstand reentry and splash in a saltwater environment. Hence, solids.
Schadow |
Fascinating Schadow and btw, I meant Albert Neuman. : 
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