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Shuttle Fleet Upgraded
angel'o'sphere writes "Space.com reports that the shuttle fleet will be upgraded with more technology, like new sensors to detect debris hits on the wings, etc. Also, the foam causing the Columbia accident (intended to insulate the tank and prevent the formation of ice) will be replaced by: heaters. I wonder if heating up a tank with liquid oxygen is a bright idea."
You definitely can heat up a tank with liquid oxygen when there's a risk of ice... if it's that cold, there's no risk of the tank becoming too hot. The cool thing is, heaters can be turned off when you don't want them on. :)
They could upgrade the fleet with some people smart enough to use some cameras to look at a shuttle wing before reentry after a HUGE ASS PIECE OF DEBRIS very obviously slams into one of their shuttles. Just a thought.
For every annoying gentoo user, are three even more annoying anti-gentoo crybabies. Take Yosh from #Gimp for example.
While it is probably a step in the right direction, I find it saddening that we must have disasters to begin upgrading certain aspects of the shuttles. In my opinion, every aspect of the fleet should always be tested, simulated, improved, and tested some more every single month. Who's to say that another shuttle won't go down in a decade or so due to a problem that was never considered?
A blog like any other.
Actually, the purpose of the foam is to keep the tanks from getting warm (as liquid hydrogen/oxygen have very low boiling points) and to keep ice from forming on the exterior.
A blog like any other.
Ditch the damn shuttle. All it does is hamper any possibility of real space usage. It is nothing more than a modern day spruce goose. It has so many things that can go wrong something will. I don't know if the nation has the stomach to lose another 7, and I don't want to find out.
And you didn't think more things could go wrong? The Apollo missions were a suicide run, if you compare the technology. And even in the future, it's likely that people will die in space. They're pioneers. Look at the recent Mars flop, where they can't get contact with the probe. Anything similar with a crew onboard would be fatal.
The US has a serious problem with lives lost. Not that it is not a bad thing and should be avoided, but sometimes there are risks involved. Like e.g. stationing troops in Iraq, and sending men into space. You must be able to accept some losses in the name of peace, progress and prosperity. Fair? Nope. But it never was, was it?
Kjella
Live today, because you never know what tomorrow brings
That's not a technical but an organizational Problem
You don't need more technology to read an email from a technician or engineer who warns because of missing or destroyed isolation foam.
The NASA has to change the way on how to react on such warnings.
Grundgesetz * 23. Mai 1949 - 30. November 2007 - http://www.vorratsdatenspeicherung.de/
The Space Transportation System (STS), which is essentially the shuttle main engines + the big tank in the middle and the two solid fuel boosters on the sides, is a fantastic heavy lift vehicle which has undergone significant testing (all shuttle flights) with one failure from which much was learnt. The take-home fact:
The STS is capable of lifting over 100 tonnes to Low Earth Orbit, or throwing 40 tonnes to Mars (with an appropriate small upper stage).
Capacity like that means humans to Mars in a decade or doubling the size of the current ISS (into something useful) in ONE THROW. Or, having an Apollo-class launcher ready for the let's-go-back-to-Luna folk.
The Shuttle, on the other hand, the Winnebago of space exploration, is a horrible hybrid device. It's essentially a portable space station, which is fine when you don't have one, but now we do. It's not a good repair vehicle (a capsule would be much better and hugely cheaper), it's not a good "escape pod" (not even the ISS uses it for that purpose), and it's not a good space transport system, because it itself weighs ninety of those precious, expensive, to-orbit tonnes.
My heart sank when I read that more space dollars were going to be spent "upgrading" this thing that has trapped us firmly in Earth's orbit for 20 years.
Come on NASA! Show some balls! Show us just a little bit of the "right stuff" you used to manufacture in bulk. Pick a destination, strip the shuttle off the stack, and GO THERE.
NASA, like many other big organisations and corporations, has long since reached critical bureaucratic mass. What this means is that ANY big change is only going to increase bureaucracy, and never reduce it. Even if the intention is to reduce bureacracy, you'll end up with NEW administrative positions creating procedures for doing so, and enough paperwork for the bureacracy reduction to warrant at least a 5% increase in administration, or if this is not possible, at least a 5% increased administrative workload for non-administrative positions.
The only way to get out of this is if a new organization or company can take the place of the old. When we're talking about government-funded large scale operations like NASA, it just isn't going to happen any time soon. Our hope, ironically enough, is that China gets their space program together. Then, and only then, can NASA die and be replaced with something less porky.
Regards,
--
*Art
People will believe that if the sensors don't show it, it must not be there. The heating systems will complicate and potentially lead to other, new kinds of catastrophic failure (as anticipated by the /. editor Michael's comment on the wisdom of heating a large tank of liquid oxygen).
This article is must reading, I think.
Well, the first stage was designed largely by the Germans. They built it simple, reliable, and strong. The original design for the Saturn V first stage (the S-1C) called for four F1 engines. When this was later bumped up to add a fifth engine, engineers found that the structure was sufficiently beefy that little extra bracing was needed. It was fuelled by kerosene (JP-1) and liquid oxygen. It was simple, rock-solid, sturdy, and reliable. It was a truly beautiful monster, and it did its job admirably.
North American designed the second stage (the Saturn S-II). Since the S-II stayed with the rocket longer and higher, weight was much more important. Liquid hydrogen had to be used for its higher energy density than kerosene. Traditional rugged German rocket engineering would have made the S-II solid, reliable--and too heavy to fly. The S-II components were designed to bear a load precisely 1.5 times the load anticipated in flight. Parts that were too strong were shaved down and tested until they failed at exactly 1.5, so as to save every ounce of weight.
Probably the biggest engineering challenge of the S-II was construction of its common bulkhead between the liquid hydrogen and liquid oxygen tanks. Despite both being cryogenic liquids, in use they're about seventy degrees (Celsius) apart in temperature. Usually this was a nonissue: the top of one tank and the bottom of the other were hemispherical, and met at only a single point. Unfortunately, such construction added weight, so for the S-II (and for the third stage, the S-IVB) a common bulkhead design was used, where a single hemisphere formed the wall between the two tanks. Entirely new techniques had to be developed to assemble the structure--miles of perfect welds were required; the metal was shaped by being pounded into a mold with explosives. And they had to do it twice for each S-II--two thin hemispheres of aluminum sandwiched a layer of insulation to make the bulkhead. Absolutely phenomenal, and way beyond anything that the Germans (or anyone else) had done before that point.
Anyway, IANAA (I am not an American) but I hate to see all of the engineers at North American Aviation and Boeing (for the S-IVB) get shrugged off--the Germans were instrumental without question in the early US space program, but credit where credit is due...the S-II and the S-IVB worked absolutely perfectly (to my knowledge) throughout the Apollo program. (Almost--a single J-2 engine of the five on the S-II failed to ignite on Apollo 13. This alone had no impact on the mission, and certainly was the smallest issue that 13 faced.)
Oh, and Apollo had redundant space crafts so even when the Service Module was blown to shreds (as a result of ground handling to empty a balky oxygen tank by running tank heaters until the insulation burned off), they brought back to crew, although one guy had a 103 F plus fever from a urinary infection because he didn't think they had enough electric power for him to take a leak often enough.
The redundant spacecraft didn't exist because NASA anticipated a possible accident (explosion of the service module) and supply an extra spaceship. There was a second ship present because the mission required it--the only way the Americans could get to the moon on a short schedule was by leaving most of the craft (command and service modules) in orbit, and landing the smallest ship possible--the lunar module. It was a lucky coincidence that Apollo 13 could use the lunar module in that way, and even then, it wasn't really designed with a 'lifeboat' capacity in mind. A favourite example is in the case of the ship's scrubbers--lithium hydroxide canister
~Idarubicin