I heard on the radio from some NASA expert that the ISS is in a much higher orbit, and that it’s trajectory was in the opposite direction of the shuttle. So the shuttle would have had to go into higher orbit, turn around, then chase after the ISS. The guy said there’s just not enough fuel for such a maneuver.
One thing he did say was that an EVA was not possible “under the safety guidelines” or something to that effect. They didn’t have the rocket packs that they use to scoot about. One thing they could have done, though, if it was do-or-die, was put someone outside, maneuver the shuttle away, then roll it until the damaged area came into view. They still wouldn’t have been able to fix it, though.
That is just abuse, imo. We should never send people into orbit unless we are going to provide them with the equipment and training so they can at least try to save their own lives. They must be given a fighting chance. This really ticks me off.
Yep. That is like putting a bandaid on a broken leg.
If you don’t inspect it, how do you know you cannot fix it?
And even if you cannot fix it, is it better to continue on without that knowledge or to at least know what you are about to attempt?
I understand the idea that a full inspection of the shuttle’s exterior is not part of standard pre-reentry procedures simply(?) because if missing tiles were discovered there would be nothing that the orbiting astronauts could do about it.
I just don’t agree with it.
Even if all that inspection could do is allow us to foresee the doom of these 7 people.
If that were a part of the standard procedure how much could have been done to prepare the families, public, government agencies, etc for what was likely to happen? How many of the questions about what happened to Columbia would already have answers? At this point we may never know what really went wrong. The most accepted theory right now is that debris hitting the wing during takeoff caused damage that was not apparent until that damage was exposed to the stress of reentry.
But that’s just a theory.
Knowledge is power. Whether it be the power to help the current situation or to find ways to prevent it from happening again.
Oddly enough this isn’t as much a comment on how the Columbia situation as it is on the mindset we (as a nation or even race type We) and NASA seem to have toward some of the dangers we know are inherent with space flight. I don’t care how complicated or impossible we know something is. Necessity is the mother of invention, but you have to know something’s necessary before you try and invent a solution.
Apparently, there was a congressional commision on the dangers of the space program in September 2001 (I’m assuming it got overshadowed by some other things…), and of course lots and lots of dire warnings. The GAO gave similar findings a year later about dangerous shortages in qualified staff. None of this necessarily would have changed last Saturday’s outcome, but it’s worrisome at the very least that people were raising this issue, and it didn’t get listened to until after the tragedy made it a political bone (even now, though I’d guess that a lot of the new funding was for the Mars program, not to help the shuttles fill their currently booked schedules as safely)
I suppose the problem is that with something like this, you’ll always have people around giving dire warnings, so it’s hard to know when to take the critics seriously until it’s too late.
i think it is rather like climbing everest. there are some places you can not be rescued from. you know this going in, and you do all you can to avoid fatal errors.
you can’t rescue someone from the summit of everest on earth. you can’t rescue someone in space above earth. you can’t rescue someone from a sub. in the mariana trench at the bottom of the ocean.
I agree that everything that is reasonable should be done to make things as safe as possible but rocking chair hit the nail on the head. Such things as the inability to inspect and repair the shuttle in flight and the impracticality of every flight carrying enough fuel to reach the space station and the docking module to make that worthwhile are common features of such endeavors.
For example, many airplane takeoffs reach a point of no return when you haven’t yet reached flying speed but are going fast enough so that you don’t have enough runway left to stop should the takeoff have to be aborted.
The airplane that I flew in WWII would lift off the ground at just about, or slightly under, single engine control speed. That is, at liftoff you had just enough airspeed to be able to maintain control should an engine fail, provided you did everything perfectly on the one and only chance you had.
When the Concorde hit that piece of junk and ruptured the tank in flight repair was not an option. If a tire blows or there is landing gear damage on takeoff, inflight repair isn’t an option. You just have to do the best you can. Of course, it is possible to have another plane check you out which might give clues as to how to best handle the sidutation and that isn’t true with the shuttle.
On risk is that political pressure will force NASA to make the shuttle so safe that nothing useful can be done.
The little tiles are not all identical. They are each shaped to fit exactly where they fit. So now, everyone wants to take an entire set of spares, and enough of a brand new fixative (the one we use now has to be applied in air, remember?). That way this one potential problem will be planned for. OK, now the other thirty five million potential problems. Hmmm, mission equipment is going to be a pretty small item on the loading manifest.
Oh, yeah, and it takes about four hundred man/years of labor to put on a set of tiles. On the ground, wearing ordinary coveralls, with gravity. If you’re trained.
Space travel is the most expensive thing the race has ever done. Thus far we have limited ourselves to very dangerous, risky space travel. If we are going to start looking for very safe, risk free space travel, it’s going to get several orders of magnitude more expensive. Trillion dollar missions, and Quadrillion dollar programs. That ought to do well at election time.
During the Mercury program, one of the astronauts was asked if he felt comfortable with the level of safety that was being provided, given that no escape mechanism was considered possible. His precise reply escapes me, but he basically said that he would still go if they told him to sit on a hat on top of a stick of dynamite and stick his fingers in his ears. I doubt that attitude is much changed among those actually taking these risks. Why do the ones who merely hear about it get so upset? There were thirty-five people killed during the original exploration by Europeans of the Shenendoah Valley, seventy miles from where I live. We haven’t done that badly, exploring space.
There were 34,000 different tiles on the Columbia, all with different dimensions (Including thickness). That means each individual tile takes about 4 man-days to place, here on earth, with full facilities, gravity, and no bulky EVA suit getting in your way. And that doesn’t include manufacture time. You can’t do a “quick and dirty” fix for those tiles. First, they have to be mounted securely. If it comes of with the first bit of reentry, it’s not doing you any good, is it? As mentioned before, the adhesive isn’t something you just slap on and it’s done, it takes a lot of time to set. And it has to be secure enough to actually hold these tiles durring reentry. Second, you have to have it in the right thickness. If it’s too thick, it disrupts airflow, and is more likely to be torn off by the force of air on reentry. Too thin, and it doesn’t provide enough protection. Third, it has to be the exact right size. The margin of error for those tiles is only a few mills, meaning they’d have to be able to precicely alter the tiles in orbit. The tiles swell due to heating durring reentry, and if it isn’t shaped right, it can pry up the other tiles around it, escalating the problem. Reentry is probably the most violent and harsh event any human-made vehicle has ever had to endure; A simple quick-fix is not going to stand up to the stress of it.
And it’s not going to be just one tile. It would probably be dozens. The Columbia alone has survived quite a few cases of lost tiles, especially on the early missions. On the very first flight, STS-1, it lost 16 tiles and suffered damage to 148(!) due to overpressure from the SRB on ignition. Redesigns to the launch pad reduced the damage to only 12 damage tiles for STS-2, but on STS-3 it lost 36 tiles, with damage to 19 more. Link, covers first 25 STS missions. So we’re likely talking 20 or more tiles, at 4 man-days apiece. Even assuming they can get two people out there, working as quick as they can, and shortcutting enough to make up for the slow-down of doing this work in microgravity and bulky EVA suits, they don’t have that much time, even if they did have the materials.
For that matter, it’s also quite possible that Columbia had every single one of its tiles intact upon starting reentry, and that the tiles had nothing to do with what happened.
Your example is incorrect. The Concorde did not have time for any repair. The astronauts would have had the time, IF NASA had done their job and checked the tiles after witnessing a potentially damaging impact. Were those tiles checked? Not to my knowledge. There certainly was no space walk to check them.
The Shuttles should all be grounded, is what I’m leaning towards now. It’s a flawed program. It’s old technology. Don’t throw any more good money after bad… Let’s replace them and do it right this time.
It would not be simple, and it would not be quick, but I am willing to bet that we have made enough progress in chemistry since the Shuttle was designed to come up with something. Even a 50% increased protection in the damaged areas might have brought those astronauts home alive. There are backup systems on all well designed vehicles. What was Plan B for the Shuttle? There was none. That is not acceptable.
You’re probably right. However, I’m thinking of something more like a temporary patch. Something that you can limp home on. Hopefully. Something that will probably burn up during the landing but keep the temperature low enough for the Shuttle to land. Maybe I’m too optimistic but I think it must be looked into if we are going to launch any more Shuttles.
I find that highly unlikely at this point, but you could turn out to be right.
I’m thinking an R-2 needs to get invented. Modern robotics are tremendously useful. Especially if they are controlled by nearby humans. A small satelite should be able to be dispatched to examine the exterior of the shuttle before re-entry. Even better would be a tele-presence-capable robot being used to repair the tiles. But either way, they should have some sort of repair kit and always carry the equipment needed to do emergency EVAs.I I feel that in light of the danger and tragedy, a better inspection plan, possible escape/rescue plans, and a repair kit usable in space should be developed.
In 30 years of materials development we haven’t gotten to the
point where we can come up with a tile repair kit? We’re not trying hard enough then, IMO. A robotic diagnostics probe and emergency repair tools, as well as contingencies for what to do if the shuttle is not capable of re-entry should be developed if they don’t exist now. Throwing our hands up in the air and saying “There is nothing we can do.” is a pathetic strategy and a dangerous attitude. There are things that can be done. They should be done. These guys understand the risks, but they should be given every chance to minimalize them we can give em.
Plus the robot could control laser targeting and be a navigational aid. It could be a kind of robotic mascot and an inspiration to kids everywhere to go into robotics. While human presence in space is where we need to go, we should go with an army of robots to do the most dangerous work. Robotic assemblers and repair drones should be possible if we can make satelites and predator drones. A merger of these (minus the stinger missiles) techs could create a valuable aid to human life in space. Let’s use some of that military robotics prowess on keeping our astronauts alive.
I just read an article in the LA Times. A former NASA engineer, Robert Quinn, says that the loss of even one 6x6 inch tile early in reentry could doom a Shuttle. Apparently we’ve been pretty lucky to get this far without a tile failure causing the loss of a Shuttle.
I read today in my newspaper that it would be possible, although quite difficult, to compensate for missing tiles by altering the entrance trajectory. In this case, if the tiles near the left wing were damaged, tip the craft so more heat would be focused on the right side. They said this would probably destroy the craft so that the crew would have to try and bail out as soon as possible. Nasa officials did not think the damage was serious enough to go for such a risky and expensive plan, but if the astronauts had gone out to inspect the damage, they could have made a more informed descision on this matter.
The inspection procedure/robots should be done before the shuttle reaches a point of no return amount of fuel or such. Do the tile check while there is still time to do something about it, like achieve a stable orbit and wait for a rescue.
What about escape pods? We can put aeroshells with rovers in them onto Mars. Is it possible to build small one-way only containers that would be able to protect someone inside long enough to parachute the inner shell into the ocean?
I thought that the cryogenic O[sub]2[/sub] tank in the Apollo 13 service module blew up because one of the wires was cracked, and the normal (not doubled) voltage across the wire caused a spark, which caused all the liquid O[sub]2[/sub] to flash to gaseous O[sub]2[/sub], thereby causing a huuuuuuuuge amount of overpressure which blew the tank apart.
Well that defeats the whole point, right there. They can’t stay up there for four days per tile, if they’re doing a non-simple, non-quick fix. If it’s twenty tiles, assuming that it took the same ammount of time it would on the ground, it would take them some 3 months to replace them (And that’s assuming they can get two people working at all times, 24 hours a day). And it would probably be more, since the Columbia itself survived a loss of almost twice that many tiles on STS-3. Even if you make it an ultra-rush job and quarter the time it takes, that’s still too long. And that’s still ignoring all the other problems with it. Heat-swelling can damage or destroy other tiles. Ill-shaped tiles can produce extra drag, which could doom the shuttle on reentry, so you have to be able to modify them to the exact size you need (Again, tollerance here measured in mills). If the adhesive isn’t strong enough, it rips away, causing more damage. Etc, etc.
Optimistic is just starting to describe it. You are vastly under-estimating the stresses put on the Shuttle durring reentry. A temporary fix will not hold. The Shuttle looses tiles occasionally durring reentry anyway, and that’s with perfectly-sized tiles, carefully placed by trained technicians, and with an adhesive that requires four days to set (With the tile pressed in place). The patch won’t burn up durring landing, it’ll probably burn up or tear off within seconds of entering the atmosphere, and provide no protection at all (As well as adding to the debris in the Shuttle’s airstream, quite possibly damaging or destroying more tiles).
Read that again. A tile lost durring reentry. Having a piece of debris rip off of the spacecraft and be thrown back along it with the force of the air is going to cause some problems; damaging or destroying other tiles, tearing up the surface of the craft, even puncturing the hull. And here, you’re suggesting a temporary fix that will almost SURELY rip off and do the same thing?
We should never send people into orbit unless we are going to provide them with the equipment and training so they can at least try to save their own lives. They must be given a fighting chance. This really ticks me off.