hmmm
Food for thought…
Thanks.
Hey Tuckerfan,
Why do you think this is?
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Incompetentence.
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Agenda.
GOM, I started this thread with the intention of it remaining a fact-driven, citation-provided discussion. Your input is most welcome, but please leave such questions to another thread, another forum.
Thanks.
Very good. Hopefully enough of the right people will be asking this question.
(Sorry about the previous hijack. I’m too curious sometimes.)
As for photography from space: Any spy satellites up there would most likely have been much further from the Shuttle than they are from Earth. It’s tempting to think “They’re both in space, so they must be pretty close”, but space is big. Even just the heavily-populated portions of low Earth orbit are big. Spy sattellites are designed to image things a few hundred kilometers away. Now, I don’t know the details of the orbit of any spy satellites, but even assuming that they’re restricted to the band which is most easily launched to by shuttles (within 30-some degrees of the Equator), they could still be tens of thousands of kilometers from the Shuttle. So now, instead of being able to resolve a license plate, you can only resolve a hundred license plates.
Someone mentioned that the Shuttle happened to pass within a few hundred kilometers of the ISS this mission. I don’t know if that’s true, but even if so, the ISS does not have a spy satellite telescope on board. So they couldn’t have gotten meaningful images, either. And with either the ISS or a spy satellite, you would have had a fairly large relative velocity, and spy sattelites aren’t designed to track other objects in orbit.
By the way, someone back on the first page mentioned the possibility that the re-supply ship just launched to the Space Station might have been diverted to the Shuttle crew, instead, to buy them some time. That probably couldn’t have been done. You’d need to match orbits with the Shuttle, which means putting that ship at an orbital inclination of 30-some degrees (the latitude of Florida). Russia’s launch facility is up at a latitude of over 50 degrees, and it’s very difficult to launch into an orbit with a lower inclination than your latitude. I doubt that the resupply ship had enough fuel. Incidentally, this is why the Space Station is in such an inclined orbit, since we wanted the Russians to also be able to launch to it. It’s some added difficulty for us to launch our Shuttles at that high an inclination, but it’s easier than it would be for the Russians to launch to a low inclination.
Slight hijack: on the topic of astronauts complaining about safety, IIRC several years ago they were speaking out because NASA had placed padlocks on the escape hatches, to which only the commander and pilot had the key. This was to prevent lesser experienced astronauts from accidently opening them or something.
Anybody know what I’m talking about? I’m really curious to hear the details…
Sorry it took me so long to return to this thread. I’ve had other priorities.
yojimboguy said:
To which I replied:
Oops, I jumped the gun on this explanation, and was sloppy in my interpretation, and overstated the confidence level. I hate that, and am sorry I fell into that trap. I was trying to point out the size of the flash on the screen does not represent the size of the material that broke off the shuttle. I gave one possible explanation that turns out was not the case.
The insulation did not burn up in the exhaust. Rather, the insulation debris bounced off the Orbiter and disintegrated. The foam in question is very brittle, not spongy and soft like foam rubber. Dittimore had a sample on the press conference the other day. It is very light, but very stiff, and very fragile. When it hit Columbia, the debris became a very spread out cloud of dust, which is what reflected the sunlight and appeared as a large flash.
tsunamisurfer said:
I did read the other posts. There were a few posted comments between mine that I reviewed before submitting the second post. I was aware of the impending March 1st launch. I was speaking in a generic case in that instant. There are serious logistical issues to either keeping one shuttle on permanent standby for launch while another is up there, or processing the orbiters fast enough to keep the next scheduled launch on the PAD during the mission. Besides the fact that 4 orbiters is a very limited number to juggle through payload processing, plus refurbishment, there’s issues of need of payloads and the costs and difficulties of keeping payloads parked in the orbiter for extended periods of time on the Pad. Some payloads, for instance, have time critical components like live animals. Various equipment must be installed in the proper sequence. Some things cannot be installed on the pad - they require the main hanger for the cranes and such. It might have been practical if Shuttle had lived up to early promises of turnaround time, but under existing conditions it just wouldn’t be feasible. To make it so would require doubling or tripling the Shuttle budget. And the likelihood of need is very small. Not zero, but that’s part of the breaks. The system works on mitigated risk. You assess the risks. You do your best to eliminate what you can, you mitigate the rest, but you accept some level of risk. It’s no different than driving a car. Maximum speed limits of 55 mph on interstates are safer than higher speed limits (proven statistically), but everybody wants to drive 70 mph.
In the case of Columbia, yes another orbiter was in processing for a March launch. That was still four weeks away. I might add that that orbiter was planned to launch to a completely different trajectory, with its own payload complement. That means all the advance planning for fuel, ballast, flight path, load balance (weight and center of gravity), stowage, etc were all calculated for a different mission. And at what stage were the preparations? How much was stowed in the payload bay, how much work was left to complete?
When and how do you decide to scramble and change the plans to launch this as a rescue mission. Obviously you need a very strong belief that the Shuttle up there will not survive reentry, or at least a strong suspicion. You do not do it on a whim, on a “better safe than sorry” situation. Look at the significant impacts to ISS schedule and operations. Look at the difficulties of planning the new launch to rendezvous with the other orbiter - reassessing your stowage conditions, recalculating balance and cg, deciding if removing components is better or leaving them in place and carrying them along. This type of planning does not happen overnight, even with everyone working 24 hour days to complete it.
If the management had serious doubts about the health of Columbia after their damage assessment, then by all means they would have tried anything - even the hail mary of rushing the rescue mission. But they weren’t there.
I’ve only heard Ron Dittimore’s response, that there was a variety of concerns during the process of evaluating the impact damage, but once the decision was reached there was no dissent on the conclusions. That fits very well with my experiences, where people question the steps along the way to ensure the right answer is being reached.
Previous flight experience trying to take pictures of the orbiter with telescopes and spy satellites did not yield results that would have made this case useful. They just didn’t have the resolution to pick out small scale damage, including a missing tile. For a large damage area (the 7 in by 32 in stripe condition), even if you could see a white stripe that should be black, you wouldn’t have any depth information to tell if it was a 1 mm or 1 inch deep gash. That would definitely affect the assessment. Plus they didn’t think a missing tile would stand out enough from the underbody to which it is attached. In short, previous experience showed empirically that pictures like that did not produce useful data.
The downside is using up resources. Retasking a spy satellite would require turning it, using up its limited fuel budget and requiring quicker replacement. Also impacts whatever else the satellite was tasked to do - monitoring potential weapons sites in Iraq maybe. So you’re talking an impact to operations for what has been shown in the past to be uninformative and inconclusive data. That’s not smart. Inundate yourself with poor quality data and think that somehow gives you more to go on than one chunk of reliable data?
Not sure what you mean. I agree that the rescue orbiter could carry extra suits. Heck, if the launch/entry suits could function for a quick-stop alternative, I could devise a method of getting them between the two orbiters. But it would be hip-pocket, and fairly risky. Perhaps not moreso than the alternative, assuming they were worried enough to mount a rescue mission. But I’m not quite sure the launch/entry suits would even work pressurewise.
Tuckerfan said:
Please back up your assertion. Ron Dittimore stated that it is and always has been to fully inform the crew of their situation. The commander is the man on the scene, and he needs to be fully informed so he makes proper decisions. John Glenn was informed of his heat shield problems. The Apollo 13 crew were present for the explosion, and witnessed the separation from the Service Module and saw the damage to it. They were well aware of the possibility of damage to their heat shield. The only situation with their flight (as dramatized by the movie Apollo 13, and we have to be careful using any movie as a definitive source, when the main goal of the movie was entertainment) that they weren’t totally informed on was their approach angle was slightly high. They had already been told once, and performed a correcting burn. As they began entry, their profile was still high. In that instance, there was nothing they could do, and there was no time for it to make a difference - send a message to loved ones, etc. Only because of both of those conditions did it make sense to withhold the information.
Jojo said:
I cannot find any pictures on the link you provide that show the shuttle in enough resolution to pick out the level of tile damage. It could tell if a wing was missing, but not the depth of an impact even if we assume the 7 in by 34 in gash.
How reliable is your random spare tile glue on process? The repair kit they tested used a caulkgun-like arrangement. They found it questionable to survive the reentry due to friction dragging the repair goo off. (It solidifies, but it is rough and uneven.) And how do you keep from making the damage worse? It’s not as if astronauts in space suits have fine control over their positioning. Astronauts kick and bump hardware on orbit all the time. It is standard procedure to require anything in the payload bay to withstand a 200 lb kickload from an astronaut. His feet are below him out of sight, his backpack (PLSS) is behind him out of sight. Now you’re asking him to navigate his way around the bottom of the orbiter, without any handholds to crawl with, and not brush/bump/kick any of the already established as fragile tiles. How is he supposed to get there? Sure he could be tied on so he won’t float away (and the orbiter could chase him down if it needed to), but what gets him to the broken patch?
As for the possibility of damage from the foam, I wonder if you’ve all seen the sample that Dittimore brought out to the press conference the other day. He had a chunk of the stuff to show what it is like. It is very lightweight, very brittle, and very fragile - even moreso than the tiles. The tiles will take a thumbnail imprint if pressed. The foam will crumble under pressure from your thumb. The foam is not rubbery like the foam in a couch cushion. It is very brittle, and has no elasticity to it. That is why they felt confident (and still feel confident) that the analysis was correct.
audit1 said:
No. The speed of the foam was governed by the velocity of the air flowing between the orbiter and the tank. It was substantially greater than the difference between upward acceleration and free fall, but it was less than the overall velocity of the orbiter/ET combination.
GOM, I think Tuckerfan gave a pretty good assessment of the article. Would I like to see a next generation space vehicle? Sure. Do I think we need to work on new technologies for cheaper programs? Absolutely. Am I ready to park the shuttles and not fly at all until a replacement is in place? Certainly not.
The shuttle did not live up to the original promises. There are myriad of reasons why, some more political than technical.
GOM said:
Yes, there is redundancy in the design. It is a reasonably forgiving design. They knew from design the tiles were fragile and could come off. The design allows for a certain amount of tile loss and still provide a safe return. The exact characteristics depend on where the tiles are, and how many at any location, etc. That is why they used the analytical computation to model the damage. That model was previously calibrated by prior experience, and they were familiar with the performance - it was a “conservative” model. Conservative means it provides a worst case situation. In this case, the model overpredicts damage. They picked conservative numbers along the way - taking reasonable guesses and then applying contingency factors to those numbers to again make it worst case scenario. And that’s why they feel the analysis results were good, and why there’s something else out there contributing to the crash.
As for rescue scenarios, the philosophy involved in the program is mitigated risk. You do a detailed risk assessment, identifying all the things that could potentially go wrong, and what the results of those problems are, and also their likelihood of occurring. Then you eliminate the ones you can, and the ones you can’t you try to reduce the impact in whatever way you can. This leads to, for example, independent redundant systems for critical items, and a two fault tolerant design. That means you can survive two independent faults (problems) and still have an operable vehicle. It provides much more safety and reliability, but at the cost of added complexity, which means more opportunities for things to go wrong. Thus it is a trade off. And then at some point you draw a line and say “this amount of risk is acceptable, and if things get this bad people die”. That may sound callous, but that is exactly the attitude you take to drive your car every day. “I’ll drive X miles an hour, I’ll squeeze this yellow light, it’s raining but I’ll still drive the posted speed limits,…” Even if you’re the safest driver in the world and strictly adhere to all the best safety driving rules and have the best judgment, you’re still at the mercy of that next guy over who is a flaming idiot and runs a red light to plow into you. But NASA doesn’t have the luxury of ignoring the risks and remaining ignorant to them. And they had to make decisions about what kinds of risks are acceptable.
And frankly, cost is a factor. To give a crude explanation, 99% of the risk takes 99% of the resources to fix, and the remaining 1% of the risk takes the other 99% of the resources. There’s a point of diminishing returns. After that, the risk you eliminate is miniscule while the expense escalates. At what point do you decide you can’t afford more safety? NASA had to make that decision. Same thing with automobiles. Cars could be made safer - and they’d cost a million dollars apiece. Do you think there’d be anyone selling and buying cars at those prices?
Dang, playing catch up is difficult.
I remember Nader’s safe car. It wasn’t that expensive. 
I just looked at the title. 
To answer; Doesn’t look like the chances of success were very good.
Three pages, and mangeorge solves in one sentence
Sheesh!
My thoughts are, that had the opportunity presented itself, that NASA may have come up with some ideas that we just haven’t thought of. Sort of like Apollo 13, when the disaster happened, NASA went to work on a solution. So, even though a rescue wasn’t planned, maybe they would have thought of something once they knew what the situation was and what the details were.
Irishman, my sources for the claims that NASA didn’t alert the Apollo 13 crew and John Glenn on his Mercury flight about the possibility of heat shield damage are the books: A Man on the Moon by Andrew L. Chaikin and Moon Shot by Alan Shepard and Deke Slayton. If you want, I can dig around and find my copies to get the page numbers where it’s mentioned. IIRC, the main reason that they didn’t tell the astronauts is that Mission Control figured the guys had enough on their minds as it was, and they didn’t need to be worried about something there wasn’t a whole hell of a lot they could about. Makes sense, when you think about it. If things are risky, you don’t want the guy with his hand on the switch second guessing himself.
Good post, Irishman. However, I think you mean, “…99% of the risk takes 1% of the resources to fix, and the remaining 1% of the risk takes the other 99% of the resources.”
They can monitor two flights. They have more than one control room. They have plenty of staff. They can monitor the ISS at the same time as the shuttle, why not two shuttles?
NASA could not have known for sure that there was a problem or they would not have let the astronauts deorbit. They would have launched a rescue mission and left the columbia up there to be fixed later. To NASA it isn’t (just) the cost in lives, valuable as these astronauts are. The shuttle cost over $2,000,000,000 for goodness sake. Why would they tell the crew to move the shuttle out of a perfectly stable orbit to burn up? If they had to sacrifice the lives of the astronauts then they would have let them asphyxyate on the shuttle. They wouldn’t destroy the shuttle. Of course murdering astronauts isn’t good policy, whether it’s during reentry or LEO.
Anyone who believes that anyone (with any power) at NASA thought that there was a chance that the shuttle could be lost if it tried to deorbit just isn’t thinking. Lives has nothing to do with it, callous as that sounds. The 2,000,000,000 dollar space shuttle and the political damage of losing 7 lives is much worse than a costly rescue mission. Not to mention the Columbia mission’s purpose, it’s mission could have been recovered. And a successful rescue mission could revitalize the interest in space exploration.
The tiles are individually customized specifically for it’s placement. They don’t have the capability to include “spare tiles.” At least that’s what NASA officials said. My answer to that was “why can’t they have a dozen oversized tiles and cut them to fit?” Still…
Boy, just imagine if they were able to image the Columbia and determined that it could not deorbit. So they rescue the crew and leave the shuttle up there for a short time, 6 months maybe. (how long could the shuttle have remained up there?) Then a crew was sent up to repair it. Who would want to ride the shuttle down after a “patch job” is done? The astronauts don’t have the training to repair a tile. They would need extensive training beforehand. Conditions are drastically different in space than they are on Earth. The people who place the tiles on Earth aren’t astronauts. They know what they are doing. I’m sure it could/would be done, but even so, I wouldn’t want to be in the patched up shuttle during reentry.
They analyzed the foam problem and determined that the damage couldn’t have been extensive. And I truely believe that the foam was just coincidental. I’m positive that it must have been due to space debris or some other cause. They wouldn’t have risked a $2,000,000,000 shuttle and 7 multi-million dollar astronauts (including the first and only one from one of our allies) without believing that the shuttle could survive reentry. Wasn’t the columbia the first shuttle to launch? What a shame!! I remember the big deal that first launch was. Even if they mothballed it, they would want it on display at NASA headquarters or at the Smithsonian.
I know this qualifies as heresay, but several astronauts have been interviewed since the accident, and questioned about the possibility of a rescue by sending another shuttle up. Also, they were questioned about repairs to the heat shield:
Rescue: rescue from another shuttle was called “foolhardy” and it was also called “a non-option”…they knew this going in.
Repair tiles: a space walk to the under belly of the shuttle is impossible without railings in the repair area, and each tile is custome fit to it’s exact location. No glue was found practical, and the patch would jeopardize more tiles.
‘Cross your fingers and hope for the best’, to paraphrase their feelings and understanding of the nature of stranded in space, because you would be surprised how much damage can occur to tiles and the shuttle can still get you home. If they knew, the only thing that would have changed would have been leaving space early and putting more eyes in the sky and more earth based rescue plans into place (in case of bad landing).
Will cite if I can. TV interviews though.
Tuckerfan, thanks. I’ll take those references and talk to some other folks.
robby, no I meant it the way I said it. The numbers don’t add up? Exactly my point. It is very expensive but within the realm of a reasonable budget to tackle a certain amount of the risks. The remaining risks are very small and require multiple times more money than has already been spent, for very small gains. I can make your $50,000 SUV .01% safer and charge you $150,000 for it. Is that acceptable to you? What about making it .1% safer and charging you $5,000,000 for it? Or would you rather take it as is and then drive a little slower and more carefully? That is exactly the type (though fudging the numbers) of situation we’re discussing.
prisoner, you are correct about the facilities. However, at one time (in the old mission control) that was not the case. Even though they had two control rooms, the limitation was in the communication and data systems. However when they moved shuttle operations to the new facility in the new part of Building 30 and turned the old Mission Control into a national landmark, they upgraded the computers and communication systems and such so that dual flight operations were possible.
You are correct that the cost of the shuttle would be of concern. However, I guarantee you (as an insider who worked for JSC) that the lives of the astronauts were of higher concern than the cost of Columbia or a replacement vehicle. In any situation where the shuttle would have to be sacrificed to return the crew alive, there would be no argument which way the decision would be made. Human lives first, then the orbiter itself, then the payload. If ejecting Spacehab would have helped, they would have done that in a heartbeat. (And no, I can’t imagine any scenario where it would have helped.)
As for carrying “oversized tiles” and trying to cut to fit on orbit, I suggest that you do not understand the difficulties of working with the lightweight tile material or the challenges of working in zero gravity, and the combined difficulties of trying to hand-shape a tile to fit an opening while performing an EVA under the shuttle without any handholds or foot restraints to anchor yourself. Try floating in a pool remaining next to the wall without touching it performing some complicated task and see how easy it is. And then realize that if they move wrong, they will kick and damage more tiles while trying to fix one set. They would literally do more harm than good trying to get to the damaged part.
What about a followup on-orbit repair mission later? At least you would have another shuttle to work from, including an RMS. It is conceivable they could come up with some way to do that, but nobody is going to work on that ahead of time because the idea is to bring the shuttle home, since the likelihood of being able to rescue the crew and not bring the shuttle home is practically nil (for all the reasons discussed before).
Philster, those comments are all correct.
Folks, please read the previous posts before posting. The tile issue, rescue logistics issues, supply of oxygen issues, EVA space suit issues, etc. have been discussed and a consensus has been arrived at. Below is an article from today’s Washington Post. It says that military satellites were indeed positioned to probably see the orbiter, but overall photographic quality is not known.
http://www.washingtonpost.com/wp-dyn/articles/A5330-2003Feb13.html
Satellite Views of Shuttle Unsought
Columbia Orbited In Camera Range
At least one U.S. spy satellite had several opportunities to take pictures of the space shuttle Columbia while NASA engineers blindly tried to determine how much damage it had sustained, according to an analysis by a Canadian expert who tracks the satellites.
During three of those passes, the shuttle was within 100 miles of the top-secret satellite – close enough, perhaps, to detect areas of damage as small as two inches in diameter.
But while the agency has asked for and received images from the military when other spacecraft were in trouble, no such assistance was sought for Columbia, NASA officials have said.
No one knows whether satellite pictures would have provided information helpful to NASA or could have changed the crew’s fate. The astronauts had no way to make repairs. But with revelations that some NASA engineers remained concerned about Columbia’s fate even after mission managers concluded there was no threat to its “safe return,” some experts are now asking whether the agency erred by not at least trying to get a better look at the shuttle while it was still in orbit.
“It could be argued that obtaining imagery would have been futile,” said Ted Molczan, a Toronto energy and engineering consultant who is one of about half a dozen hobbyists around the world who meticulously track America’s spy satellites in space, and who did the orbital analysis and provided it to The Washington Post. “But it could also be argued that an image of the defect that caused the break-up would have been invaluable diagnostically, even if vehicle and crew could not have been saved.”
And further in that article they discuss reasons why the imagery could probably not be good enough, why retasking a satellite is not a simple, easy, or cheap thing, and reiterated that the program asked themselves that question and relied on past experience to make the judgement.
Tuckerfan, I do not have those books and have not read them. I asked the question here:
http://www.badastronomy.com/phpBB/viewtopic.php?topic=3877&forum=3&12
The reply has been that John Glenn was informed, that was why they left the retropack on the bottom of his capsule, and there were subsequent discussions of the possibility of his landing bag having deployed. Transcripts from the flight:
http://www.lib.ohio-state.edu/arvweb/glenn/flight/canton2.htm
http://www.lib.ohio-state.edu/arvweb/glenn/flight/hawaii3.htm
http://www.lib.ohio-state.edu/arvweb/glenn/flight/cape4.htm
main page http://www.lib.ohio-state.edu/arvweb/glenn/flight/flightmain.htm
As far as Apollo 13, the crew was asked to take pictures of the SM after it separated. This would include looking at how far the damage spread, such as did it make it to the SM/CM boundary, which would suggest damage to the heat shield.
I have yet to get any information regarding the books, but have asked about them.
Irishman, your answer regarding Glenn and the books can be found in my last post in this thread. I was incorrect in asserting that NASA didn’t tell Glenn. They weren’t going to tell him, but evidently Glenn put up such a fuss that they did tell him.
Regarding Apollo 13, here is an excerpt from A Man on the Moon*, Book Two, Chapter Seven. The astronauts have discarded Aquarius and are now back in Odessey, just a few hours prior to reentry:
So the Apollo 13 crew were already aware of the hazard of damage to their heat shield. No need for Mission Control to tell them.
Okay, are there any outstanding issues in this thread? Did we pretty much answer the OP?
I ran across this article from a few weeks back, outlining a potential shuttle rescue operation
Basically, it involves sending up an unmanned emergency supply payload to extend Columbia’s life in space while the next shuttle is prepped (no need to accelerate the launch schedule), then putting Columbia into a power-saving mode for a few weeks.
The author claims the most difficult aspects of this would be
- Getting the emergency payload to a compatible orbit (this might take several attempts)
- Doing the spacewalk to retrieve it
I’m glad this thread has been revived. We know a low more about what happened, and a lot more about what, IMO, are serious NASA fuckups.
Mid level engineers were extremely concerned. Senior management blew them off, and even overturned an informal request for ground imageing. It turn out there was a good chance that ground imageing might have been high enough res to pick up damage . Boeing modeling software predicted a burn-through but was discounted. NASA responded as a clunky, paralysed bureaucracy, a pale, shameful shadow of its former greatness.