The Rise and Fall of NASA's Shuttle-Centaur (arstechnica.com) 53
An anonymous reader writes: An article at Ars Technica tells the story of Shuttle-Centaur, a NASA project during the mid-1980s to carry a Centaur rocket to orbit within the cargo bay of a space shuttle. As you might expect, shuttle launches became vastly more complex with such heavy yet delicate cargo. Still, officials saw it as an easy way to send probes further into the solar system. They developed a plan to launch Challenger and Atlantis within 5 days of each other in mid-1986 to bring the Ulysses and Galileo probes to orbit, each with its own Shuttle-Centaur. Though popular opinion at the time was that the shuttle program was "unstoppable," individuals within NASA were beginning to push back against slipping safety standards. "While a host of unknowns remained concerning launching a volatile, liquid-fueled rocket stage on the back of a space shuttle armed with a liquid-filled tank and two solid rocket boosters, NASA and its contractors galloped full speed toward a May 1986 launch deadline for both spacecraft." The destruction of Challenger in January, 1986 put Shuttle-Centaur on hold. The safety investigation that ensued quickly came to the conclusion that it presented unacceptable risks, and the project was canceled that June.
So... (Score:4, Interesting)
It's a rocket with a ridiculously heavy intermediate stage that serves no function but to endanger lives if anything goes wrong.
I guess when you have a hammer...
Re:So... (Score:5, Interesting)
The shuttle was supposed to replace all US launchers, because that was the only way to get the flight rate high enough to get anywhere near the original cost claims. Centaur was required to launch heavy payloads, because the solid-fuelled stages that fit in the shuttle's payload bay simply couldn't do so, and the shuttle would be the only option.
I knew there were safety issues with it, but I hadn't realized just how bad they were until I read this article. Someone should have told them it was batshit crazy well before they got that close to launch. Then again, this was the NASA that thought it could ignore engineers and launch Challenger with frozen, leaky SRBs.
Re:So... (Score:5, Insightful)
I knew there were safety issues with it
The biggest safety issue was using a manned flight for something that didn't need people. All other things being equal, you will have 10 times the death rate if you launch 100 manned missions rather than 10 manned missions and 90 unmanned rockets. When the Challenger exploded, killing 7 astronauts, it was on a "stick a satellite in orbit" mission, that did not need to be manned.
Re:So... (Score:4, Interesting)
I knew there were safety issues with it
The biggest safety issue was using a manned flight for something that didn't need people. All other things being equal, you will have 10 times the death rate if you launch 100 manned missions rather than 10 manned missions and 90 unmanned rockets. When the Challenger exploded, killing 7 astronauts, it was on a "stick a satellite in orbit" mission, that did not need to be manned.
The thing is that the Russians had developed their own space shuttle (the Buran), which they abandoned. The interesting thing in this context is that the Buran was fully automated; in its test flight it had no crew (the Russians thought it was too dangerous!) it took off and landed all controlled by automated systems or from the ground.
Now if the US space shuttle had this capability perhaps these Centaur launches would have been possible.
Question is, why didn't the USA develop the automated/remotely controlled capabilities that the Russians had??
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The thing is that the Russians had developed their own space shuttle (the Buran), which they abandoned. The interesting thing in this context is that the Buran was fully automated...
The Buran had no main engines on the orbiter, instead they were on the external fuel tank. It would have been possible to launch the Buran with something like the Centaur strapped to the side in lieu of the orbiter. Why bother hauling the extra weight?
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Question is, why didn't the USA develop the automated/remotely controlled capabilities that the Russians had??
Because: cowboys.
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But yet the Russians didn't develop the Buran under the idea that it would be some sort of cost effective space taxi like the shuttle was sold to the American people as. The Buran (as revealed in the 2000s from soviet archives) was developed solely to avoid a "missile gap" situation with the US.
When the shuttle was announced the Soviets shrugged their shoulders, they already had something cost effective and didn't see the benefit of such a vehicle for them. When the size of the cargo hold was announced they
Re:So... (Score:5, Insightful)
But yet the Russians didn't develop the Buran under the idea that it would be some sort of cost effective space taxi like the shuttle was sold to the American people as. The Buran (as revealed in the 2000s from soviet archives) was developed solely to avoid a "missile gap" situation with the US.
When the shuttle was announced the Soviets shrugged their shoulders, they already had something cost effective and didn't see the benefit of such a vehicle for them. When the size of the cargo hold was announced they raised an eyebrow. But when the wing specs where revealed there was no longer any question that the shuttle was also intended for some very dangerous military applications, up to and probably including the covert testing of weapons in space in such a way that the Soviets wouldn't know the Outer Space Treaty was being broken until it was too late and there was a proven killsat over Moscow.
No it wasn't. The wing specs were because the DoD spec was to be able to launch into polar orbit, deploy a satellite, and land at the launch site on the same orbit. The Earth will have rotated about ~1500 miles in that time, so it needed 1500 miles of cross-range to get back to the launch site. That set the size of the wings.
Of course most of their suspicions where true.
If those really were their suspicions, none of them were true.
Frankly, the shuttle would have made a lousy weapons platform-- too big, too fragile, too visible. Really a weapon isn't useful when there are only two places it can launch from, and any launch is telegraphed weeks in advance and is visible from hundreds of miles away.
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Of course most of their suspicions where true.
The US had several platforms for launching killsats that would have been more effective and an order of magnitude lower cost than the Shuttle. For example, the killsat could be ballast on a Delta II or Saturn IB flight.
The DoD was responsible for the crazy shuttle modifications that killed its original benefits in favor of it being useful to the military to perform single orbit covert missions. But then the US military changed their mind after it was built and NASA was left holding the bag (and 7 members of STS-107 died for a never used 1000 mile cross range capability).
And if NASA hadn't built a Saturn V replacement, then they wouldn't have needed DoD funding. The DoD shouldn't bear blame for poor NASA design decisions.
Also, if you look at it from the DoD's point of view, the Shuttle simply didn't live up to its promises from NASA. They didn't launch it
Re:So... (Score:5, Interesting)
You're almost right. The crazy shuttle modifications were so that they could bring a Russian satellite back. They are apparently somewhat heavy. And bulky.
Thus the truck of a shuttle we ended up with; about the power of a Saturn V, and yet couldn't even get to geosynchronous, much less go to the Moon or anything.
The interesting question is; did they steal a Russian satellite? Would the Russians blow it up if a shuttle approached? Did they include a self destruct? (I guarantee they have one now.)
Is that the real reason we discontinued the shuttle; since you can't steal Russian satellites anymore, there's no point in having one?
Re: So... (Score:1)
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Question is, why didn't the USA develop the automated/remotely controlled capabilities that the Russians had??
The shuttle was capable of automated flight, if you connected the computer to a handful of systems that were designed to be manually controlled for safety. For example: the landing gear couldn't be deployed by the computer, because there was no way to raise it again... a bug that caused it to deploy in space would have been fatal.
But the more cynical would claim it was just because NASA wanted an excuse to put astronauts on board.
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in its test flight it had no crew (the Russians thought it was too dangerous!)
Well, they had copied the US designs, and I guess even with their improvements they still didn't quite trust it! ;)
Question is, why didn't the USA develop the automated/remotely controlled capabilities that the Russians had??
The real question is why didn't NASA just buy it off for next to nothing after the fall of the Soviet Union. I mean they ended up relying on much older Soviet technology to get to the ISS, it would have been so much better to have salvaged that nice Buran project...
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The shuttle actually has one of the lowest failure rates of all launch vehicles (depending on how you estimate the error bars on vehicles with a small number of launches).
https://en.wikipedia.org/wiki/... [wikipedia.org]
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So, why not launch the Centaur in place of the shuttle (with appropriate unmanned controls) instead of inside the shuttle? Seems like 2 SRBs and a simple hydrox engine should get the job done.
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Because launching it on an Atlas or Titan would have been much cheaper.
Otherwise, you'd need to build a new pod with some SSMEs in it, and then either figure out a way to get the SSMEs back, or write them off on each flight; AFAIR they cost around $50,000,000 each. Were there any other LOX/LH2 engines at the time which could have been used?
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Well, using KSP sensibilities, if the mains are too expensive for you, just use more SRBs, but, yes, it is mostly a case of "we built one hammer and it was so expensive that we had to use it on all the nails.
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The problem is that the SRBs only burn for two minutes. You'd have to add several more, and start them sequentially in flight.
It would certainly make a great firework display^H^H^H^H^H^H^H^H exciting video.
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No humans on board, 30G liftoff not a problem - will need to clear the atmosphere before firing the final stage, though...
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Since the same engineers had been telling them for five years that it was safe to launch with leaky SRB's (A part that's usually left out of the tale and most people are unaware of*) - I think NASA was more than justified in being a little skeptical of their last minute change in heart that they offered no justification more.
* That's why NASA was able to trot out a revised joint design so fast
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As the design change proved, it was safe by spaceflight standards... provided you kept the joint temperatures above the level at which significant erosion happened. Below that, you were playing Russian Roulette.
It's one thing to say 'sure, the shuttle is safe to launch in July', and quite another to say it's safe when the temperature was below freezing overnight. Managers should understand the difference.
Once again, you've only got half the story. (Score:2)
Well, again, that's the soundbite version - and only half the truth. In reality, the worst cases of leakage prior to the loss of Challenger occurred with launch temperatures in the eighties. In reality, the real problem wasn't temperature but a phenomena called joint rotation. That's why the redesigned joints included heavier clevis pins at
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Re: So... (Score:2)
Huh? Yes, SRB's can leak (Score:2)
BTW - when they're burning, SRB's produce very hot gas which damn well can leak .
Read the Wikpedia article [wikipedia.org] on the loss of the Challenger or just search Google for "space shuttle challenger accident [lmgtfy.com]"
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They don't know why it sealed though... whether it was flexing of the case, or condensation of the exhaust gases forming a temporary plug. (IIRC, there was signs that the latter may have happened during previous burn through and blow by incidents.) But it goes to show that the accident is much more complicated than the "it got cold, it go boom" urban legend version.
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Oh, everyone with a modicum of perspicacity knew the thing was a boondoggle from the start.
http://www.washingtonmonthly.c... [washingtonmonthly.com]
That text offended the delicate sensibilities of the Space Nutter crowd, but now that the Shuttle, along with other Space Age fantasies, is safely in a museum, we can read the text and go "yup".
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That'll be news to the people who bought the satellites it returned from orbit after their boosters failed.
But I think the original quote related to satellites that had been in space for years, and run out of fuel, or had important systems fail.
So it's really possible (Score:1)
I used to say the Shuttle was probably capable of a whole lot more than what we knew of its capabilities (Even though it is NASA, and supposed to be fully transparent) - using its cargo capacity for extra fuel always seemed like a no-brainer to me. I had no idea this was actually pursued in a form, but it is a shame real life finally caught up to NASA and all the cool technological advances have been under military secrecy since then.
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using its cargo capacity for extra fuel always seemed like a no-brainer to me.
It is actually not a good idea. You need chemical rockets for the initial boost to get out of the atmosphere and into low earth orbit, because you need to get there quickly. But once you are in orbit, chemical rockets make little sense. It is much better to use ion thrusters, which are slower but far more efficient, to climb to higher orbits, or to head beyond earth orbit.
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"It is much better to use ion thrusters"
Now of course, but back when this program was created Ion propulsion was in its infancy here in the US. If the shuttle had become what they had hoped I have little doubt that would have become a launching pad for Ion/Vasimr craft. There are also a few situations when you need a lot of thrust quickly so a chemically powered shuttle launched rocket would have made some sense. But this thing seems like an exercise in stupidity, any such system should have been enginee
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The only way NASA will get to Mars is by film.
Nah, the CIA came up with that Stargate program mind/psychic thingy and then DIA got it, they'll share and next thing you know we will have weather reports of a baron planet! Then again they can always dream and at this point with the financial situation in the US this would be the most realistic approach. Nothing like feeling one's contract of citizenship has: "content with being on a bus load of retards" in the fine print. Perhaps they can put that in place of the 4th.
Challenger Abort to Orbit Video (Score:2)
Better Way (Score:1)
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By now we should be building the rockets in space and just delivering the materials from Earth.
By now we should be building rockets in space using materials from space. FTFY.
Wat? (Score:3)
Dammit Slashdot! We need more of this sort of thing, and less of people being pissed off because something got a file extension of .bro.
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Slashdot articles are generally taken from submissions. (Except for the Slashvertisements, of course, but they're still "submitted" from somewhere.) If you want more articles like this, someone will have to find them and submit them. Slashdot doesn't create these things out of thin air; a Slashdot article is basically a link with a blurb to an article somewhere on the interwebs that someone entered into the submission page.
Many many articles are submitted, and someone has to determine that they are worthy of posting on the website.
At present, we have at least one "editor" who likes all the hate and derision - and the clicky clicky it gets. Perhaps Women in STEM should get it's own category, like some other topics.