As long as this is the case, rather than just throwing our hands up and saying “there is nothing we can do”, which seems to be the attitude of some. A robotic tile repair procedure should be possible, even if it means holding tiles in place for 4 days in an “atmosphere tent” to allow it to seal properly.
Scan and repair needs to be an option once the shuttle is in orbit. A mix of EVA and robotics should be able to achieve this with some effort.
Anyway, I think we should devote a large chunk of space resources to a space elevator now. Let’s see if anyone can weave a macro-scale cable out of carbon nanotubes (CNT’s). I have not heard of any attempts to do this. I’ve heard plenty about the substantial increase in creation of CNT’s, but no research into stringing them together.
I’m more and more inclined to say fuck the shuttle for the most part. Use it to maintain and finish the ISS and that’s it. Work on an elevator and a next generation space plane. Send greatly enhanced robotics and probes to really stake out the solar system (and other ss’s as well). Use nuclear propulsion to enhance the science return and speed of these missions. When the elevator is finished, build a couple of ships that never land anywhere, rather they travel back and forth like ferries to and from points of interest: Mars, Jupiter system, asteroids and the Moon.
Build the infrastructure to turn space into the vibrant economic opportunity it must become. The shuttle was supposed to do this but has failed. Cheapen the process (assembly line style) of building advanced robotic probes, send out an armada while we build the elevator, minimize human presence for now, and in 15 years start sending well equipped human missions to establish industry and new leaping off points.
If they turn the shuttle into an ISS-only vehicle, it solves your in-space inspection problem. You can use a camera on the end of the Canadarm on ISS to fully inspect the shuttle, and if it’s damaged the crew could stay on the station long enough for a rescue flight. In the meantime, the engineers on the ground could have a year or more to work out a repair mission for the shuttle.
I wouldn’t be surprised if we saw that shuttle used that way from now on, save for a few military missions. That would put economic pressure on new launch initiatives, including private launchers. Might not be a bad thing, as long as there is a plan to have an alternative launcher cheaper than the shuttle but with the same payload capacity.
The huge political pressure to have “reusable” manned space vehicles was far more powerful than the pressures to provide the real lowest cost solution to low and medium earth orbit satellite launches. A lot of folks back in those early days of the shuttle program said it wouldn’t work for precisely the reasons that it is now not working.
When something breaks down in space, you lose the vehicle. If it has a crew, folks die. So, you have to rebuild the shuttle every time and you still never know what you might have missed. You only find out about failures of design by watching the design fail. Now, to add in the design requirement that every Shuttle be self repairing sounds delightful. But the cost of what little could be done along this line is mind boggling.
It may not have been the tiles this time. But the fact is that it will eventually be the tiles, someday. The incredibly meticulous work needed to put tiles on the shuttle on the ground is simply not going to be done in space by a crew trained in any other mission technique. There are thousands of systems involved in each aspect of the mission. Failure under stress means catastrophic consequences. And fixing them in freefall, in a vacuum, while wearing a space suit is a major undertaking even with specific mission training. And only being able to fix ten percent of them is not going to satisfy the safety requirements of a system that holds every mission hostage to every failure.
Planning to be able to fix every possible failure during the flight is unachievable. Why diagnose things you can’t fix? If we had a hotel or garage up there, we would have been parking in it long before this. But do you have any kind of idea what such a thing would cost? NASA is not going to get ten times the funding they have now. It isn’t going to happen. They are going to have to politically showboat safety for a couple of years, just like last time. And it won’t change a thing in real life.
Double the number of shuttles, and launch facilities, and always have ships prepared in pairs, one of which never leaves the ground except in emergencies? Oh, yeah, that ought to be just real cheap. And it only helps if you know in advance that you have a problem, which we haven’t, to date. The people who were watching decided that the foam collision probably didn’t do damage, and it seems to be the thinking now that they were right. So, what did? We don’t know now. How the heck were we supposed to know in time to launch this proposed second shuttle mission?
It also means that every shuttle mission has to be cut in half for duration, and significantly for payload, to allow enough time and fuel for all the proposed safety precautionary maneuvering. So, now we need four times the shuttles and twice the launching facilities, and we haven’t even gotten all your self inspection and repair stuff on board. A second generation of shuttles will not be coming on line nearly as quickly, either, given the additional safety engineering that is being considered here.
And now, for a word from mission control. “Sir, we want to send up the second shuttle, and bring the crew down.” . . . “Well, sir, we have some film of liftoff, and it seems we might have had a collision with some ice particles on the trailing edges of one of the wings.” “No sir, we aren’t sure.” “Well, sir, it’s no problem getting the second shuttle up, and by using up all its reserve fuel, the first one can stay in space for another three days.” “No sir, after that it will just crash and burn on reentry.” “Yes sir, a total loss.” “Yes sir launch conditions and systems for the second shuttle will be exactly the same.” “No sir, we can’t send up a third.”
No one will be second guessing that poor soul, will they? Come on, make multi-billion dollar call, on the fly, and tell your boss to just write off a shuttle you think might not make reentry. And send up another shuttle of the exact same design to save it.
Tris
“If God had intended for man to go to Mars, He would have given us more money.” ~ an unnamed NASA official ~
NASA’s even checking on the possibility that some of the shuttle tiles were defective.
Which means that IF some of the tiles were defective, a visual inspection could very well have been useless, since it might have appeared that there was nothing wrong with the tile at all.
I recently read a technology article (I can’t find the article but it wasn’t blueprints like Popular Mechanics) about the use of robots that could be employed to inspect and repair shuttles.
Premise: It’s dangerous to send astronauts on ESV’s (space walks) where they’ll go out of visual range. And NASA has no “tile-caulk” to repair tiles.
Solution: Let’s have robots at least inspect the shuttle craft. Let’s discover our options if there’s a significant breach. Let’s figure out a way to make those tiles in space. Or maybe if we had a Space Station that could serve as a lifeboat, or the ability to launch a support vessel… we’d no longer have to resort to the pseudo-science of Wishful-thinking.
The Shuttle isn’t flying again until much of this is covered. We need space robots that can either crawl or fly under the shuttle. They’ll need cameras. The ability to repair damaged spacecraft in space seems far-fetched now - but maybe not someday.
I also heard that possibly the workers had been adding water to the glue that holds the tiles on. The water supposedly speeds up the curing time for the glue, but it also reduces the glue’s gripping strength.
Caution: This could just be a rumor. I haven’t found anything in print about this yet.
I think that was about some workers on previous missions that had been found doing that before, and got into lots of trouble for it. I havn’t heard anything about the people that set the tiles for this one, though (Appart from someone saying that the workers added water to deliberatly sabotage this flight. Right…)
Old news. That problem dated back to Challenger and was supposed to have been eliminated since then. The workers weren’t simply pouring water in the glue, either, they were spitting in it!
I heard Jay Barbree almost complain this morning that he hasn’t been able to get an answer from NASA about exactly who installed the last set of tiles on the Challenger. He thinks it could be important. He could easily be right. After all…
“Jay Barbree has covered every manned space mission in U.S. history. All 144 of them.”
In the first few days after the Columbia disaster, NASA showed surprising candor and openness, effectively allowing the public to peer over the shoulder of the mission manager each day.
That all changed when an independent board took over the investigation and engineers were told, in effect, not to talk to reporters."
I’m not surprised that NASA’s telling the engineers to keep quiet. The last thing they need is some engineer telling the press his pet theory on what caused the accident. The moment he does that, then every reporter will be on the horn to NASA demanding to know what NASA thinks of said engineer’s theory. Nevermind that anyone with a bit of science edumacation would know that said engineer’s theory was full of shit. (Remember back in the 80’s when an engineer claimed that every space shot stole gravity from the Earth?) NASA needs some quiet time now to be able to figure out what the hell happened. They don’t need to be responding to every halfwit with a question about something he read in The Weekly World News. (“Is it true Bat Boy was photographed on the wing of the shuttle just before it broke apart?”)
IMHO, the shuttle is a high tech combo 18 wheeler/rv. Unfortunately, it’s 70’s high tech that’s been patched up. The concept is nice, but it’s wrong.
What I feel we need are 3 types of space vehicles. Maybe just 2.
A reusable manned vehicle capable of transporting a number of humans from earth to earth orbit and back.
A one way unmanned lifter capable of transporting cargo/satellites/etc from earth to earth orbit.
(optional) An unmanned reentry vehicle that can be boosted into earth orbit by vehicle 2 that can then have, say, a satellite strapped down inside it so the satellite can be returned to earth.
You can’t have a single vehicle that does everything well. If I want to travel across I-70 as quickly as possible I want a Ferarri. If I want to go across 1-70 with the wife and kids I’ll have to sacrifice some speed and gain some comfort and take the Buick. If I want to take a refrigerator across I-70 I’d be better off with a Ford F-150. If I want to take 6 buddies with me across I-70 on a 2 week road trip to do some research I’d probably want some honking Winnabago. And if I want to transport 32,000 lbs of windshields for Chevy Trailblazers, I want a Peterbilt. But ONE freaking vehicle to do all of the above? You’ve got to be shitting me.
That’s what the shuttle was designed to be. Nearly anything at all that is as complex as the shuttle will be obsolescent by the time it is operational.
Isn’t this what is routinely done with weather, communication and spy satellites.
The NASA lack of resources to do everything that would be nice is a conscious, political decision. Until something bad happens, the public is perfectly willing to keep NASA on short rations and the political establishment follows that lead.
Are you sure about this? From Glenn’s recent article in Newseek it sounds like he knew what was going on:
Wouldn’t the decision not to throw away the retrorocket pack be such a significant departure from the normal procedures that they would have explained to Glenn why they didn’t want him to do it? if for no other reason than that he wouldn’t panick when flaming chunks of it started flying off?
Slight correction. I just dragged out my copy of Moon Shot and found the section which deals with Glenn’s flight. I won’t retype the whole thing (mainly because it’d be over “fair use” standards), but here’s what happened:
Glenn was told to leave the retropack in place. Chris Kraft and Operations Director Walt Williams didn’t tell Glenn why because they didn’t want to alarm him. Glenn asked Canton CapCom why, they told him he’d be briefed when he came in range of the Texas station. When Glenn got in range of Texas CapCom, they merely confirmed the order, and he was unable to get anything else out them before passing out of communication range. When Mercury Control from the Cape came into range Glenn got his answer.
So I was right in saying that NASA didn’t want to tell Glenn, but wrong in asserting that they didn’t tell Glenn.
I note that the book (which was co-authored by Shepard) does say “finally,” which probably means that Glenn must have been really bitching at NASA to get them to tell him what was going on. (Glenn was a straight-laced kind of guy, who got in arguments with the other astronauts over their wild ways. He says now, that it probably cost him a mission or two. So no doubt, they must have put Shepard on the horn because they were tired of hearing Glenn go on about it.) It also does adhere to NASA’s policy of having critical information dealing with deviations from mission plans delivered by a fellow astronaut (Shepard hadn’t been grounded by his inner ear problem yet). The reason being that if the guys upstairs hear it from one of their own, they know it’s passed the “bullshit” test.
I’m slow coming in here, but I’m going to try to add some information. I hope I’m not too repetitive.
First, for those thinking an EVA inspection should be done, consider this: it is a given that the tiles are fragile. That’s why you’re inspecting for damage. Astronauts in spacesuits are not ballerinas - it’s like the “bull in the china shop” cliche. An astronaut can kick with a 40 to 50 lb force without realizing he’s doing it (at least until it bumps something). They cannot see their feet, nor their backpacks. It is highly probable that the very act of trying to get below to do the inspection would cause more damage than you’ve already suffered. Even if you could repair the damage, you’re making more work in the very process of getting there to do the job (or even just look). Thus the reason NASA decided to forego any spacewalks outside of the payload bay. The potential to cause more damage is greater than the very small risk that is mitigated by the inspection.
The suggestion of a robotic inspection device has merit for future implementation. I believe packages of this sort are under research and development. A robotic camera with nitrogen thrusters was flown as a test on a previous mission (SPRINT, on STS-87 IIRC). This was actually a concept for use on ISS build to help monitor the astronauts while working and provide TV coverage to the ground and visual recordings. It was subsequently decided to use helmet mounted cameras for ISS work. This is advantageous in a number of ways. However, some derivative of SPRINT technology could potentially be developed for future Shuttle inspection.
However, it is one thing to have a camera that can take a look. It is quite a different thing to try a robotic repair kit. You’re talking very complex tasks that are not pre-programmable. And as previously explained, even if your robotic camera detects tile damage, any EVA repair would likely cause more damage. And that’s assuming you are flying the necessary repair equipment, including tools to help you get to the underside of the orbiter.
What about a thruster for the astronaut, like SAFER? SAFER is a small unit attached to the underside of the spacesuits for ISS. It was developed as contingency safety equipment in the event an astronaut accidentally got separated from the ISS and his safety tether broke. The Shuttle can maneuver after an astronaut released in this manner (whieh is very unlikely), but since the ISS cannot chace him down, the SAFER was built.
SAFER has a limited supply of fuel for the thrusters (IIRC it uses nitrogen gas). It has plenty to perform a limited safety stop and return of a displaced crewmember based on speeds the astronaut could conceivably get pushed off. It can even stabilize a tumble. However, a short duration safety return is a lot less fuel than a long duration inspection of the underside of the Orbiter. That thing is freaking huge. And you’re going to want to go slowly to make sure you see everything. So you’re going to need a much larger thruster pack.
What about the Manned Maneuvering Unit (MMU), flown in the early days for satellite recovery? This is a larger unit with more fuel capability. Something like that would perhaps have the capability, but now you’re talking the need to carry the MMU on every flight, which takes up not only weight but space in the payload bay.
Some of you have pointed out that the orbiter does not often carry it’s max rated payload. However, it almost always has the space in the payload bay accounted for. You are looking at one payload limitation but ignoring others.
Now consider this: do you think NASA looked at the fragility of the tiles and then said, “Well who cares”? You think you spot what hundreds of engineers somehow missed? In fact, NASA is well aware. Thus, they designed the system to be very tolerant of tile damage, attested to by the data provided by Phoenix Dragon on numbers of tiles sustaining damage or missing on previous flights. They tried their best to make the system as robust as possible, precisely because the ability to repair was not practical.
Brutus said:
Actually, Intelsat repair fits the bill as unplanned. Circa 1992, there was a repair mission sent to an Intelsat that was not designed to be retrieved by the shuttle or repaired on orbit. However, NASA developed some methods and tools to try. When the planned grappling techniques failed, they tried a three person EVA. The fact that they had three EVA suits suggests that they had considered that possibility, but I think they had two EVA crews (and four EMUs) like they fly on Hubble missions to alternate days. After the planned techniques failed, astronauts on the ground went out to the training facilities and tried out techniques for the three person task. They had to come up with how to place three people to attempt to grab the bottom of the satellite (which did not have any handles) by hand - a risky proposition. Can you say “glove damage”? They also had to come up with a technique to get three astronauts into their EMUs simultaneously and into the airlock. Anyone who has seen mockups knows how tiny the middeck and airlock of the Shuttle are. It is also very tricky to wiggle into the suits in zero gravity (and on Earth), because of the shape of the hard upper torso unit, and getting arms/shoulders into the sleeves of the joints. It is a fairly crowded task when two people do it. Three took some extra contortions. However, the ground testing worked, they discussed it with the on orbit crew, who pulled off the first (and only) three person EVA. And they made it work - captured Intelsat and repaired it, and released it again.
A second opportunity for a completely unexpected EVA occurred on STS-75 in 1996, on Tethered Satellite. The satellite was a ball on a string, that was deployed off a boom from the payload bay on a wire some 10 miles behind the shuttle. This was done to develop tethers for space applications, and study the environment and electromagnetic effects. A problem on deploy of the satellite caused a short that severed the tether, and left the satellite free floating 7 miles behind the Shuttle. When this occurred, NASA considered the possibility of retrieving the satellite in order to bring it home. Techniques were discussed, including all the safety implications. In the end, this EVA was not performed because of other program concerns, notably getting the two close enough and not burning off all the fuel within the time constraints by the resources of the flight. It was an unexpected scenario that was evaluated and selected against.
But the essence of your post is correct. NASA does not like to leave things to chance. There are three types of spacewalks. The “planned” tasks are as they sound, things that are planned to occur nominally on the flight. “Unplanned” tasks are really a misnomer, or more a different application of the word. These are tasks that are backups and fallbacks for the planned tasks. They are developed in detail and practiced, just like the planned tasks. The third category is “contingency” EVAs. These are the “something goes wrong” category. Again, while these are not expected or wished to be done, they are thought out and developed and practiced ahead of time.
NASA spends a lot of time and man-hours deciding what can go wrong with any payload and mission. They think out any problem that might arise, and how an EVA might be used to solve the problem. There are criteria for evaluating these possible problems. Much effort goes into developing these scenarios and training for them, even though you hope to never use them.
Which goes back to my point - EVAs to inspect/repair the orbiter were considered, evaluated, and the risks determined to be greater than not performing the EVAs. This is not negligence, it is careful consideration of all the implications, and balancing the risks for the safest course of action.
CrankyAsAnOldMan said:
How do you train to do something that can’t be done?
scr4 said:
For the record, they did have two space suits. They always have at least two space suits. There are several contingency scenarios involving failure of shuttle hardware, such as the payload bay doors failing to latch properly, or failing to close at all, or the S-band antenna getting stuck and not able to stow automatically. They carry the tools for these tasks on every flight, and the capability exists to perform an EVA to cover these possibilities. The Spacehab had a crew transfer tunnel from the main airlock to the lab. This tunnel included an airlock and hatch to the outside.
The other pressure suits you mention are the orange launch/landing suits. These were developed post-Challenger. While they are pressure suits, I don’t think they are designed for the vacuum levels at orbital heights. They are for cabin pressure losses at lower heights and for crew escape (bailout) scenario. You can’t bail out until after the S-curves have finished, and you’ve slowed down to below the speed of sound.
robby said:
I think you have a misconception of how things work. Yes, they try to plan everything they can. Yes, they practice and train for everything. But they spend considerable effort in trying to determine what can go wrong, and what to do about it, and how to fix those problems if they are fixable. This is called being prepared. You would hate to hear, “Doh, we didn’t think of that.” Of course, this is coupled with an evaluation of the probable risk, vs. the cost and tradeoffs of solutions. But regarding EVAs, while they try to think of all possibilities and then prepare responsibly. But just because they prepare extensively for all conceived possibilities that does not mean they exclude the unexpected. For instance, there is a whole set of tools flown on the Shuttle that do not have known task. When deciding what tools they needed, one thing they did was include some tools that were generic possible use - such as a prybar like a crowbar. There is no known scenario for use of the prybar, but they fly one anyway just in case. Being prepared for everything you can think of does not mean you are neglecting what you can’t think of.
Regarding the specifics of Columbia, they did not change operations because they did not perceive a need to change operations. If there was enough concern, they would have altered to suit the need. You think it relevant that they didn’t do an EVA, but it has already been explained why an EVA would do more damage than good. See above. You don’t do something that makes things worse on the off-chance you might learn things were too bad to begin with. They deorbited on schedule because by that time the analysis had not shown the problem great enough to warrant dramatic action (such as attempting to rush a rescue flight).
They continued planned operations because that is what they were there to do, and there was no cause to change operations. The crew could continue to perform their scheduled science while the ground evaluated and analyzed the impact. Would you have preferred they told the crew to stop all science, and sit on their hands? What happens if you have them do that, and then the analysis says their’s no cause for alarm? Now the mission is half over and nothing has been done. And from the payload perspective, their objectives are shot to hell. And then they come safely home on schedule because they don’t have the resources for extra on orbit time to make up for the lost time while they did nothing.
You’re concentrating on what they didn’t do that you feel they should have, but how are you are qualified to judge what they should have done? You are neglecting what they did do, which is gather all data they felt would be helpful (as opposed to gathering data they thought would be useless), and then performing a conservative analysis of the damage, then evaluated the results for the impacts to the flight (including crew safety), and finally made an informed decision to the best of their ability. And they informed the crew about the situation, and kept them apprised of the status of their work.
No, that was not an assumption. That was an evaluation based on the film that they inspected, past experience, and the design of the hardware. The behavior of the object that fell was that of foam that has occurred before, including the large flash of light seen that is from the object disintegrating into a dust cloud. What metal object is going to disintegrate into a dust cloud, especially after impacting the already stated as fragile tiles? What metal part could have fallen? How could a metal part have come loose in order to fall?
As for how much that information influenced their analysis, I’m sure they were aware of it but I don’t think it was a significant influence on the evaluation of the damage. I’m sure it played a role in the decisions of what to do, in that they considered all the options available based upon the suspected level of damage. But they wouldn’t blow off the analysis “because there’s nothing we could do anyway”.
Actually, there is plenty of provision for working out problems just like Apollo 13. And crew initiative is the same, too. But you seem to think that the Apollo 13 crew solved the problems themselves. In fact, it was a huge effort by the ground that provided solutions to bring the crew home safely. For instance, the contingency adaptation of the carbon dioxide filters was not developed by the crew, but by the ground. Apollo 13 was a collaborative effort between the crew and the ground, with decisions reached jointly. Columbia was the same - they communicated with the crew what was going on. The crew’s ability to add meaningful contribution to the evaluation was limited, so they played a limited role in the process.
Regarding a long term mission such as a Mars mission, where communication with the ground would be subject to longer delays and more possibility of interruption/loss of signal, NASA will definitely need to evaluate and adjust their operational strategy to meet the mission requirements. This will likely mean the crews will exercise more flexibility. However, just because they would do a Mars mission differently does not mean the current philosophy is wrong. They are different circumstances with different requirements and different limitations.