Was the Space Shuttle an inherently bad idea?

[dlrk]

We've all heard about the many mistakes of the space shuttle. The cost cutting, fragility, expense of launch, etc. What I'm wondering if any of the experts here can shed some light on, is if the concept was bad, or the execution was bad.

Was the basic idea of a mostly reusable piloted spaceplane to launch humans, satellites and cargo a bad idea? Or was it NASA's execution that was bad?

[rpayne88]

IIRC, the problem with it was the high maintenance costs involved, as well as the requirement to produce a new ET for every flight. What I don't understand is why they strapped the orbiter to the side, where it could be hit by ice or superheated gases from the SRBs, rather than mount it on top.

[DaveofDefeat]

It was just one of those things that sounded really good on paper, but didn't work out so well in the real world.

[bsalis]

Yes, as amazing as it was, it was a bad idea. It was meant to be safe like all manned craft, and cheap as well from being re-usable. It turned out to be neither.

[NovaSilisko]

Tthe two biggest problems with the space shuttle were, in my opinion, using the same platform for both crew and cargo, as well as having literally no abort scenario before the SRBs jettisoned.

There are advantages to having crew on a cargo launch platform - astronauts in space are a lot better at fixing problems on the fly than any sort of robotic deployment system, but... given the inherent safety problems with the vehicle, I'm not sure the risk vs reward there really pays off. Ironically, the one big mishap that could have been prevented by having crew present - Galileo's main antenna failing to deploy - didn't occur until well after Galileo had left the reach of the shuttle.

Hubble was an additional case that the shuttle did well at - although, it must be said that Hubble itself was designed specifically to be launched and maintained by the shuttle, so I would say it's not unreasonable to think that if a different manned vehicle were operating at the time (a capsule with cargo pod, for instance), the design of HST and plans for servicing would be different accordingly.

[Streetwind]

The space shuttle as a combination crew/cargo orbiter with atmospheric flight and return capability enabled many missions that would have been outright impossible with a less capable craft. Just think of the SpaceLab missions - carrying a pressurized, manned orbital research module up, operating it there, and bringing it back down gently with all experiments intact was huge. As such, the shuttle was not a mistake. For its time, it was the most advanced spacecraft ever built, and allowed science to learn more about zero-g environments in a few flights than in all manned and unmanned missions prior combined.

The mistake was using the shuttle as a common satellite launch vehicle or for ISS supply runs (for which is was far overpriced) and using it well beyond its safe operating life (because the US had no budget for anything new and it was THE symbol of spaceflight).

[Nibb31]

It sounded like a good idea at the time, so you can't really blame them. Hindsight and all that...

[czokletmuss]

All spaceplanes have one big problem - you are taking wings into space. Which means that although you have rocket with, say, 100t to LEO capability you are going to use some of it for wings and all the plane stuff. Which doesn't make sense really, since you are just wasting several tonnes. Of course, the reliability and the possibility of reusing the shuttle combined with cheap maintenance and increased flight rate was supposed to overcome this. We all know how this worked out.

IMHO spaceplanes are inherently a bad idea and a dead end for manned space exploration (I know there is Skylon but it's years from the first flight - and don't remember that STS also was supposed to make things easier and cheaper).

[Simon Ross]

The original concept was fine.

A small, reusable space plane capable of carrying a crew of 3-5 people into LEO with a small <5 ton science payload. The Shuttle would have been much more a lifting body type shape, no large delta wings and a much less complex configuration.

To secure USAF support, the Shuttle grow massively from it's original design concept and capability into the delta winged monster we actually ended up with.

As others have already stated, it's pretty much the kiss of death when you start mixing man carrying capability and cargo carrying capability into a single design, it ends up not doing either of them particularly well

[Klingon Admiral]

I, for one, am still wondering if the space shuttle would have been a better system if NASA had stopped caring about reusability and just mass produced orbiters, with one version transporting purely cargo and another carrying only people.

[MaverickSawyer]

As with most high-budget items, it wound up falling victim to compromises and politics.

[Kerbin Dallas Multipass]

If you regard the potential military threat the shuttle posed, it was an idea so brilliant that the soviets went through the effort of designing and launching their own clone.

For civilian spaceflight purposes the shuttle is just ill-designed IMHO. Not because of any particular flaws but because the entire concept is just too "luxurious" and resource-inefficient.

I would say NASA can be criticized for using SRBs, yet not even thinking about a launch escape system. I also wonder why there was no mandatory procedure to inspect the airframe before initiating reentry (every hang glider pilot does a "walkaround" before takeoff). So yea, safety-wise: What were they thinking?

[Guest]

It could've been viable if the system was completely reusable. Like early Shuttle concepts, or Energia 2-Buran concept. Liquid boosters, either flyback of parachute recovery, main tank flyback and a more efficient reusable orbiter would make it much cheaper, and if they built it more rugged, it could've been safer and even cheaper. I'd say, if they borrowed some solutions from Buran, it could end up flying much longer and much cheaper. American approach is to build everything to tight tolerances and using cutting-edge tech. Soviets, on the other hand, built things much more rugged. The latter approach would've served the Shuttle much better, even if it wasn't so goo for expandable LVs.

[CaptRobau]

Using the Shuttle both for military purposes and civilian purposes is what ultimately caused it to reach its full potential. The USAF wanted a 1000-mile cross-range capability so that the Shuttle could be used for launching military spacecraft. This meant it had to have the wings it did. These relatively large wings influenced much of the rest of the design, limiting the use of it as a civilian spacecraft. Another problem with the Shuttle is that it was designed to be part of a larger fleet of spacecraft. The Shuttle to ferry cargo and crew to orbit, small space tugs to move things around in orbit and larger nuclear space tugs that would transport (manned) craft to the Moon and beyond. In the end we only got one piece of the puzzle.

So while spaceplanes like the Shuttle aren't a bad idea in themselves, the way the Space Shuttle was designed and used left much to be desired. While it did a lot of wonderful things, for the money it cost a lot more could've been done. Perhaps an Apollo continuation which, without the added cost of developing new tech, probably could've done much more with the same amount of dollars.

[Themohawkninja]

Neither of the things that you said were bad (well, sort of the execution, but only specifics).

The two problems that I see in it, is that: (A) Even though NASA knew that foam has fallen off of the external tank before the relevant disaster, they didn't bother to do any physics calculations/tests until after they lost a shuttle, and ( They decided that since an issue was unexpectedly fixing itself, there wasn't any point in actually solving the problem in the first place... which led to the other disaster.

Other than that, the fact that it was given so many tasks didn't hinder it from what I can tell. NASA just wasn't extremely responsible about the whole thing when they really should have been.

[Themohawkninja]

It could've been viable if the system was completely reusable. Like early Shuttle concepts, or Energia 2-Buran concept. Liquid boosters, either flyback of parachute recovery, main tank flyback and a more efficient reusable orbiter would make it much cheaper, and if they built it more rugged, it could've been safer and even cheaper. I'd say, if they borrowed some solutions from Buran, it could end up flying much longer and much cheaper. American approach is to build everything to tight tolerances and using cutting-edge tech. Soviets, on the other hand, built things much more rugged. The latter approach would've served the Shuttle much better, even if it wasn't so goo for expandable LVs.

Borrowing from the Buran is just indirectly borrowing from the Shuttle. The Buran became a Russian Space Shuttle copy, the only difference being possible unmanned mission launches (I don't regard an unmanned test launch an example of unmanned abilities), and a possibly more rugged design (while Russia is known for lower tolerances for better durability, I have yet to see the design specs on the Buran to see if that is actually so).

[Wahgineer]

I, for one, am still wondering if the space shuttle would have been a better system if NASA had stopped caring about reusability and just mass produced orbiters, with one version transporting purely cargo and another carrying only people.

Ala shuttle-C?

[Nibb31]

Borrowing from the Buran is just indirectly borrowing from the Shuttle. The Buran became a Russian Space Shuttle copy, the only difference being possible unmanned mission launches (I don't regard an unmanned test launch an example of unmanned abilities), and a possibly more rugged design (while Russia is known for lower tolerances for better durability, I have yet to see the design specs on the Buran to see if that is actually so).

You should take a closer look at Buran. The similarities with the US STS are only superficial. The main difference was that Buran's main engines were on the Energia launcher and were expendable.

This has a huge impact on the economics and even the sheer point of reusing the orbiter vehicle. The whole point of the reusing the orbiter was to bring back the engines for reuse. If you're dumping the most expensive part of the vehicle, then there is no need to bother with all the extra spaceplane bits and just bring the crew back in a capsule.

The concept didn't make sense, even to the Russians, who weren't stupid. But in the 70's-80's, the Soviets were totally paranoid and were fully expecting Nixon or Reagan to initiate a first strike against them. They figured that if the Americans were making a space shuttle, there must have been a military purpose behind it, so they wanted the same capability, even though the actual military purpose didn't make sense.

[H2O.]

I think the shuttle design is a classic case of à la swiss army knife device. Yes, it seems to make sense to have only one craft for different missions, at least on a cost point of view. But as the number of missions increase, the number of compromise increase too and you end-up with a spacecraft that can do a lot, but not do anything great.

• crew : 7, it is actually the better asset of the shuttle, however it prooves rather unsafe
  
• cargo : 18442$ per kg in LEO (compare to 10476$ per kg in LEO for Ariane 5 ECA for instance, and it is not the least expensive, sources : wikipedia)
  
• payload recovery : rarely used (only for spacelab ?)
  
• military polar missions capabilities : never used
  
• long crossrange capabilities : never used
  

What appears here is actually pretty simple : the shuttle was a machine without a clear mission.

I have seen on YouTube a video of Neil deGrasse Tyson. He want a modular do-it all spaceship. I think it is a very strange way of using technology. Usually, you design something because you have a very clear goal. It is always a bad idea to create a machine and wander what to do with it after.

Edited January 15, 2014 by H2O.

[crazyewok]

What appear here is actually pretty simple : the shuttle was a machine without a clear mission.

Sounds like NASA in general

[czokletmuss]

What appears here is actually pretty simple : the shuttle was a machine without a clear mission.

It was a job program and an ideal way of transfering federal money to future voters and big guys in the aerospace industry.

So I say mission accomplished BTW doesn't this remind you of something?

[H2O.]

BTW doesn't this remind you of something?

That's just mean

[Kerbin Dallas Multipass]

@Themohawkninja

@Nibb31

Dragon1 was talking about the Energia II concept which was planned to be fully reusable. In both (I and II) designs the Buran shuttle was just an optional configuration, the system could be used as a heavy lifter for any payload.

Edited January 15, 2014 by Kerbin Dallas Multipass

[TheSaint]

Using the Shuttle both for military purposes and civilian purposes is what ultimately caused it to reach its full potential. The USAF wanted a 1000-mile cross-range capability so that the Shuttle could be used for launching military spacecraft. This meant it had to have the wings it did. These relatively large wings influenced much of the rest of the design, limiting the use of it as a civilian spacecraft.

This was really the root of the problem. The original NASA shuttle design (the "DC-3" design by Max Faget) was a small shuttle that would have had very little cross-range capability. It would have rode a reusable first-stage booster. There would have been no solid rocket boosters, and since the first stage would have required its own thermal protection system there would have been little or no ice buildup problem. But when they brought the budget proposal to the administration, Nixon got sticker shock and told them to go see if they could share the project costs with the Air Force, who was also in the market for a reusable spacecraft at that point. The Air Force wanted to be able to launch the vehicle into a polar orbit from Vandenburg AFB in California, deploy a satellite, then land at the launch site after one orbit to minimize the vehicle's exposure to anti-satellite weapons. This required the 1,000-mile cross range capability, which dictated the large delta wings to provide increased lift, which pushed the reusable first-stage off the table and led to the cascade of design compromises that led to the shuttle design we all know. Ironically, after the Challenger accident, the Air Force decided that the shuttle design (which they had essentially dictated to NASA) was too unreliable and expensive to operate, so they dropped their involvement in the shuttle program and started the EELV program, which developed the Atlas V and Delta IV rockets that are still in use today.

The other political disaster in the shuttle program was the SRBs. When the contract for the SRBs was put to bid, Aerojet proposed monolithic boosters (one piece, no jointed segments) that would have been constructed and serviced at their existing facility that was a short drive from KSC in Florida. Morton Thiokol proposed construction and servicing of the SRBs at their facility in Utah, which required that the SRBs be produced in segments that could be transported by rail to and from Florida. They were more complex and much more expensive. But, in closed-door negotiations with NASA, the head of the Senate committee on Space Science, Frank Moss (who just happened to be the senior senator from Utah) made it abundantly clear that the funding for the shuttle program would die in committee if Morton Thiokol didn't win the contract. So, MT won the contract, the SRBs were segmented, and seven astronauts died in the Challenger accident.

[Firov]

The other political disaster in the shuttle program was the SRBs. When the contract for the SRBs was put to bid, Aerojet proposed monolithic boosters (one piece, no jointed segments) that would have been constructed and serviced at their existing facility that was a short drive from KSC in Florida. Morton Thiokol proposed construction and servicing of the SRBs at their facility in Utah, which required that the SRBs be produced in segments that could be transported by rail to and from Florida. They were more complex and much more expensive. But, in closed-door negotiations with NASA, the head of the Senate committee on Space Science, Frank Moss (who just happened to be the senior senator from Utah) made it abundantly clear that the funding for the shuttle program would die in committee if Morton Thiokol didn't win the contract. So, MT won the contract, the SRBs were segmented, and seven astronauts died in the Challenger accident.

While not ideal, the segmented SRBs weren't actually a serious problem, and Challenger wasn't a result of any particular flaw of the SRBs or the shuttle itself (Yes, yes. O-Rings, but read on). Unlike Columbia, the Challenger disaster was due purely because of horrible management on NASA's part, and could have been avoided by simply postponing the launch for a day or two.

The SRB's had been designed and tested around specific launch conditions, including the temperature. On the day of the Challenger disaster the temperature at the launch pad was well below the minimum rated temperature of the SRBs. The MT engineers recognized that the O-Rings were well outside of their rated safe temperature and expected that they would be brittle enough to crack, and as such, completely unsafe to launch. The engineers obviously urged NASA to wait until a warmer day to launch.

NASA management knew about all of this as they had the SRB design specs and had consulted with Morton Thiokol about the launch temperature that day, but in the end they decided that since the SRBs hadn't failed yet, it was completely impossible for them to ever fail, no matter the launch conditions. This is a distressingly common thought process in NASA it seems. Anyway, with that in mind they decided to disregard not just the original design limitations of the SRBs but also of the engineers who actually built the things and launch anyway. As a result of NASA's management, Challenger and her entire crew were lost .

While large monolithic boosters could probably have handled a launch that day due to the lack of O-Ring seals, the fact of the matter is, they shouldn't have launched that day at all, and they knew it beforehand. As such, it's not entirely fair to claim that the SRB's were inherently unsafe. Anything can, and likely will, fail if you try to use it well outside of it's original design limitations.