Posted on 02/04/2003 1:34:19 AM PST by bonesmccoy
In recent days the popular media has been focusing their attention on an impact event during the launch of STS-107. The impact of External Tank insulation and/or ice with the Orbiter during ascent was initially judged by NASA to be unlikely to cause loss of the vehicle. Obviously, loss of the integrity of the orbiter Thermal Protection System occured in some manner. When Freepers posted the reports of these impacts on the site, I initially discounted the hypothesis. Orbiters had sustained multiple impacts in the past. However, the size of the plume in the last photo gives me pause.
I'd like to offer to FR a few observations on the photos.
1. In this image an object approximately 2-3 feet appears to be between the orbiter and the ET.
2. In this image the object appears to have rotated relative to both the camera and the orbiter. The change in image luminosity could also be due to a change in reflected light from the object. Nevertheless, it suggests that the object is tumbling and nearing the orbiter's leading edge.
It occurs to me that one may be able to estimate the size of the object and make an educated guess regarding the possible mass of the object. Using the data in the video, one can calculate the relative velocity of the object to the orbiter wing. Creating a test scenario is then possible. One can manufacture a test article and fire ET insulation at the right velocity to evaluate impact damage on the test article.
OV-101's port wing could be used as a test stand with RCC and tile attached to mimic the OV-102 design.
The color of the object seems inconsistent with ET insulation. One can judge the ET color by looking at the ET in the still frame. The color of the object seems more consistent with ice or ice covered ET insulation. Even when accounting for variant color hue/saturation in the video, the object clearly has a different color characteristic from ET insulation. If it is ice laden insulation, the mass of the object would be significantly different from ET insulation alone. Since the velocity of the object is constant in a comparison equation, estimating the mass of the object becomes paramount to understanding the kinetic energy involved in the impact with the TPS.
3. In this image the debris impact creates a plume. My observation is that if the plume was composed primarily of ET insulation, the plume should have the color characteristics of ET insulation. This plume has a white color.
Unfortunately, ET insulation is orange/brown in color.
In addition, if the relative density of the ET insulation is known, one can quantify the colorimetric properties of the plume to disintegrating ET insulation upon impact.
Using the test article experiment model, engineers should fire at the same velocity an estimated mass of ET insulation (similar to the object seen in the still frame) at the test article. The plume should be measured colorimetrically. By comparing this experimental plume to the photographic evidence from the launch, one may be able to quantify the amount of ET insulation in the photograph above.
4. In this photo, the plume spreads from the aft of the orbiter's port wing. This plume does not appear to be the color of ET insulation. It appears to be white.
This white color could be the color of ice particles at high altitude.
On the other hand, the composition of TPS tiles under the orbiter wings is primarily a low-density silica.
In the photo above, you can see a cross section of orbiter TPS tile. The black color of the tile is merely a coating. The interior of the tile is a white, low-density, silica ceramic.
I think the best thing is to send it to NASA.
DITTOS... it's probably a piece of ceramic from something else. HRSI is not that dense.
This don't sound good. From http://www.chron.com/cs/CDA/ssistory.mpl/nation/2686055
July 16, 2004, 10:39PM
Return-to-flight costs soar. NASA estimates the cost of safety updates may reach reach $1.2 billion
By MARK CARREAU
Copyright 2004 Houston Chronicle
PROJECTIONS
NASA estimates for cost of returning space shuttles to flight with safety measures developed after Columbia:
• For 2004: $450 million, up from $256 million
• For 2005: As much as $650 million, up from $238 million
The cost of returning NASA's three space shuttles to flight could reach $1.2 billion, more than double the January estimate, space agency officials said Friday.
The shuttles were grounded in the aftermath of last year's deadly Columbia accident. NASA plans to resume launchings as soon as March or April for missions that include completion of the assembly of the international space station.
The pace of reactivating the fleet, however, increasingly has become dependent on the willingness of Congress to approve NASA's budget for the 2005 fiscal year, which begins Oct. 1.
It's good to see y'all active here...
4403 - thanks for the ping and the update. From your post, it seems that nothing much has changed.
4403 - here is a bit more of interest from your link, another snippet:
"The Columbia Accident Investigation Board subsequently called for 29 safety improvements. Those included repair kits for spacewalking astronauts to patch any damage and modifications to the fuel tank to prevent foam loss.
Urged by the board to look for other hazards, shuttle managers discovered potentially serious problems with gearing in the rudder that steers and slows the spacecraft as it descends to a landing. They also are looking for potential problems with fuel lines, electrical wiring and flex hoses."
Glad they are locating some of these additional problems, but as they sit longer and longer, the problem list will grow.
NASA again reporting as simplistically naive, and/or politically correct as possible, maybe those 4(?) astronauts took their gloves or helmet off because they were still alive and slowly burning to death in the long-intact crew compartment. That also would leave evidence that they had suffocated and not burned to death.
from FLORIDA TODAY By John Kelly
... "The report did not provide specific details about how the crew died or how long the seven might have survived, only that the compartment was intact for almost a minute longer than the rest of the ship.
In general, the report said the astronauts did not burn to death. They died from suffocation when the cabin did finally rip apart and from the force of colliding with other objects at incredibly high speeds as the wreckage fell to the ground.
The report also recommended future crews be carefully trained to wear all of their protective gear. The forensic review showed three of the seven astronauts were not wearing their gloves and one was not wearing a helmet. The report said, however, that none of that would have increased the astronauts' chances of surviving the Columbia break-up."
I have been researching the Columbia disaster since soon after it happened. Although my conclusions disagree with the official investigation I am not now nor ever have been a conspiracty theorist. I believe that I am simply someone who has stumbled on to something.
I have not posted anything I could not prove through engineering methods or by sound reasoning. I do not expect anyone to accept all or any of what I have posted and I present it only as an alternative to the official conclusions.
http://www.columbiassacrifice.com
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Poppycock! That is exactly what you are doing.
Your idea that the OEX recorder was planted is absolutely hilarious.
This kind of thinking is not at all productive. I'll not even address all your ideas, except to say that each one can be refuted and the refutations backed up with evidence.
Skorpious, all your 8 preliminary questions have been addressed and answered, right here on this thread, long, long ago. Read through the thread from the beginning.
http://www.space.com/missionlaunches/ft_tank_repairs_040813.html
There is Added Urgency to Shuttle Fuel Tank Repairs
By John Kelly
FLORIDA TODAY
posted: 13 August 2004
08:04 pm ET
NEW ORLEANS -- The detective work is ending. Now it's time for the men toting spray guns to get to work.
In a hulking factory on the outskirts of New Orleans, they're finally starting to rebuild the fuel tank that will fly with Discovery on the first shuttle mission since a chunk of orange foam from another tank made here led to the destruction of Columbia and killed seven astronauts.
Only this time, after building and flying more than 100 of the behemoth tanks, everyone working on this tank knows the leeway for mistakes is far smaller than anyone imagined. Nineteen months of tests show a piece of the lightweight foam as small as a hamburger bun can bring down one of the mighty space shuttles.
"This is not easy," said Neil Otte, the tank's chief engineer, during a media tour Thursday of the Michoud Assembly Facility, where the tanks are made.
NASA and Lockheed Martin Space Systems Co. admit they will never completely eliminate the decades-old problem of foam popping off the tank during shuttle launches. They're convinced, however, that they've figured out how to dramatically reduce the size and amount of the foam chunks that batter the orbiters' brittle heat shields.
"This tank is going to be much safer," said Sandy Coleman, the manager of NASA's external tank project office at the Marshall Space Flight Center in Alabama. "We want more than anything to protect our astronauts. They're part of our family."
She is not alone delivering that message. In the hallway just outside the doors the tank-builders must pass through is a poster of the next shuttle commander, Eileen Collins, holding her daughter. The poster's sobering slogan: "Are you ready for us to go? Think safety."
Making the tank much safer, NASA found, goes far beyond the decision to lop off the suitcase-sized foam triangles called "bipod ramps." It was one of those foam ramps that popped free during Columbia's flight, punching a hole the size of a car tire in the orbiter's left wing. As Columbia plunged back through the atmosphere on Feb. 1, 2003, the superhot gases that envelop the orbiter got inside the wing and ripped the spaceship apart.
So the ramps on External Tank No. 120 are gone. Instead of the foam, a heated copper plate will keep ice from building up on the V-shaped metal struts that hook the tank to the orbiter. A slight change in the metal will keep the material from overheating on the way to space.
NASA decided on that change a few months after the accident, but engineers and managers gave the final go-ahead for workers to retrofit Discovery's tank a month ago.
That's just the most visible change. Several others were prompted by newfound knowledge that foam far smaller than the 2-pound piece that hit Columbia could be deadly.
To hold it in your hand, the foam weighs less than a Styrofoam beer cooler. Hence, NASA's long-held assumption that the stuff could do nothing more than gouge pits in the heat-shielding tiles that were a headache to repair but not a danger to the ship or its crews.
Columbia exposed that as folly. Reaching more than twice the speed of sound in the first couple of minutes after blasting off from Kennedy Space Center, the shuttle is moving so fast that blocks of foam the size of a coffee cup could hit with enough force to open a deadly gash in the orbiter's protective armor.
Another dangerous assumption: NASA assumed the foam was applied perfectly, every time. After the accident, investigators sliced and diced other tanks being built here and found air pockets, cracks and other flaws that could cause foam to pop loose.
Robots spray a near-perfect layer of foam across about 95 percent of the tank. In hard to reach places with bumps, grooves or other odd surfaces, men spray or pour the foam into place. That's where most flaws hide.
"That wasn't the fault of the guys putting it on," Otte said. "They were doing the job that we gave them and it was just a tough job."
Instead, Otte and his team found, the application process itself contributed to the defects. NASA and contractor teams wrote procedures decades ago as they designed the shuttle, but apparently never checked to see whether it worked. What came out of the factory never matched the design.
The Columbia Accident Investigation Board chided NASA for not doing more study about how the foam fails. The post-accident studies drove the changes.
A thick ridge of foam covering a seam where the hydrogen tank is bolted to the cone-shaped oxygen tank is being reworked. Nitrogen inside the tank has been creeping through tiny gaps in bolt threads, into air pockets in the foam, later expanding to pop foot-wide divots. Now workers are spraying there more carefully, eliminating hidden voids. They're also injecting insulation into the tiniest of crevices.
An exposed spot along a fuel pipe outside the tank is being retooled so water will drip away instead of forming a thick, potentially deadly ice ring. Another ramp-like section of foam will be sprayed more carefully to avoid any chance it might pop loose.
Some ideas came from tank workers. Others designed by engineers were perfected in countless practice sessions by men who've been coating the tanks with foam for 20 years.
"You've got to let them practice," Otte said. "You've got to give them the right process that they can do over and over again." The sprayers now get to "try different things until they find something that works that they can do consistently."
Michoud is due to ship the tank, via ocean barge, to Kennedy Space Center by October or November to meet a spring launch date.
"Quality of that tank is first and foremost," said Hal Simoneaux, the Lockheed Martin manager heading the tank retrofit. "If we have to take a schedule hit to get it right, we will."
Skorp - as a newbie - you should know that we expect more professional responses here on FreeRepublic. We have experts on just about every subject, particularly, space, among many others. We welcome contributory new members.
RA - ping my last post - sorry, I didn't mean to neglect you.
Yet the stonewalling about the change in solvents and blowing agents continues. To my knowledge, NASA has never acknowledged that changing from Trichlorethylene to the "citrus scented" solvent had any part in the foam coming off.
When bonding, surface preparation is the most important factor for a good bond.
I don't ever recall seeing a four square foot (2'x2') hamburger bun...
They were at the "Big Bun" hamburger joint. And as I recall the commercial, it was about a 18-inch diameter bun!
I sometimes forget to wear my seatbelt in the car but I refuse to believe, with all of the checklists on the shuttle, that one of the astronauts did not have their helmet on.
4415 - "Yet the stonewalling about the change in solvents and blowing agents continues. To my knowledge, NASA has never acknowledged that changing from Trichlorethylene to the "citrus scented" solvent had any part in the foam coming off."
Very true. I remember when they got rid of MEK too. Last I heard we were 'cleaning' parts with pure 'water', though my information is now out of date.
Didn't someone on this thread suggest that the foam should be *inside* the tank? I think it's just bad engineering to rely on foam as an exposed structural member in supersonic flight. So what if they have to reduce the maximum to-orbit load.
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