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Space Shuttle - Good or Bad


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Merits of Russian/Soviet and American honesty aside I agree with the original position that the Space Shuttle was a dead-end that nearly killed NASA as a space agency stone dead.

Whatever the merits of it's design specifications it was fundamentally flawed and crippled because the most highly stressed component was reusable and carried a great deal of dead weight for most of the mission. To qualify;

The landing gear was dead weight until landing

The engines were dead weight once orbit was achieved

The wings were dead weight until reentry

All these points lead to a higher reentry speed and poor glide capability

So the vehicle couldn't lift much due to the extra structure and needed a large crew to launch anything. In most cases a disposable launcher was far cheaper and safer. If the shuttle had been designed the other way around it may have worked. A totally re-useable vehicle to carry an orbital vehicle and it's booster to altitude, booster places the vehicle in orbit. Mission performed, booster parked near space station for use as a orbit decay solution then dropped, vehicle reenters like a large Apollo capsule behind a replaceable heat shield. Parachutes deploy for final descent, heat shield dropped then a final brake for a soft landing on Earth or ocean.

All the stressed items are used to destruction, the vehicle itself could be serviced for reuse very rapidly. Whatever is left of the heat shield could be sold for scrap :thumbsup:

NASA banked everything on a huge space station to follow Apollo, after spending on the Apollo Applications Programme. The amount of money spent on endless studies that never produced any hardware will probably never be known. The shuttle was conceived to supply a space station. When the station finally died after the infamous '90 Day Report' NASA needed a mission for the shuttle and eventually built the ISS. They lost 30 years and priceless experience. Madness IMHO.

No, the Shuttle was a disaster for NASA and the USA, the true extent of that mistake will never be understood.

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Exactly my view too.

And it's one thing to say that astronauts know the risks and take their chances. In most respects that is true. But as regards the Shuttle, the problem that doomed Challenger was NOT known to the astronauts - so that was one risk they were totally unaware of.

And, to make matters worse, NASA was trying to convince Congress that the Shuttle was an operational vehicle - fit for "non-astronauts" to fly in. That was a downright lie and immoral at the very least.

I don't understand Major Eazy's stance to be honest. Is he of the opinion that discussion of matters that are now historic are irrelevant - purely because the topic is historical?

I find that very, very strange. I would argue that the Shuttles may be retired - but the impact the whole programme has had on NASA and manned spaceflight is profound and long lasting - and has a legacy that will persist for decades.

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The space shuttle wasn't bad per se, it was the concept that was flawed. There was a mad rush to get a reusable space vehicle (all through the '60s this was a stated ambition of NASA) that would make trips into Earth orbit quick and routine, 'till this day it is neither. That along with the hope as pointed out above of a large orbiting space station akin to Kubrick's 'Space Station V' in 2001 by the mid '80s was the perceived wisdom of the day.

A stack of things conspired against that vision, it would need a book to explain the undoubtedly varied and complex reasons why the above was not fully realised, but two huge contributions were the public losing interest in space exploration and the consequential reining in of expenditure on the space programme, NASA saw neither coming. That a long along with space shuttle not being panacea for an easy route to orbit, it was anticipated be at the outset.

Marty...

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A good summary of the background. By the early 70s there were no votes in space - so there was no money forthcoming from Congress.

The Shuttle ended up being a bit of a dog's breakfast of a design. NASA felt they had to go ahead with it or else give up on manned spaceflight completely. They knew there would be problems but they went ahead anyway.

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The manipulation of the US Public's attitude to space is another sorry tale altogether. Tricky Dicky saw it as an easy target to cut to divert funds to the people who had supported his Presidential Campaign, the US Public had rejected him before but the big bucks overcame their doubts and killed the 'American Century' stone dead. Congress and the Senate went along with it in exchange for getting out of the Vietnam war.

@Marty With respect everything about the shuttle was a disaster for space exploration and NASA. The materials that may have made it feasible weren't around (some still aren't), the concept was flawed, the engineering had far too many compromises. It was approved for service in about the same state of development as the Apollo 1 capsule. That showed serious design flaws at the cost of three brave men, the individuals who were responsible weren't in the capsule. It was exactly the same with the shuttle. I can find nothing to commend the whole shuttle era except as an example of how not to do it. That's a pretty poor return for the lives lost.

As a final thought remember that the Apollo drawings and engineering data were destroyed rather than archived, that was a condition of the granting of funds for the shuttle. The genius of the design teams of the day is revealed by the efforts to reproduce the concept 50 years later. Unable to work out how to separate the command and service modules they went to the preserved unit in Florida and had a look......and were so proud that they put the film on their site.

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Marty - if the CONCEPT is flawed then everything that flows from it has to be flawed too. You can't start off completely on the wrong foot -0 which is precisely what happened with the Shuttle.

As I've heard elsewhere regarding the difference between Apollo and the Shuttle -

Apollo - the simplest and most reliable approach taken to achieve a complex mission

Shuttle - the most complex approach taken to achieve a simple mission

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The shuttle was conceived to supply a space station.

It eventually did, but it was Mir.

And while it was useful for sending up ISS modules, the Russians managed to build their part without it. The station could have been built in a fraction of the time using HLVs like the Saturn V or Energia..

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Considering I have been following shuttle for many decades, I've thought about the debate from both sides. What I've found is that the shuttle itself is NOT a failure. Its only real failing is in how it was marketed and utilized. Back when NASA designed the thing, they were also trying to sell congress on the concept of a space tug which could tractor satellites up into higher orbits AND bring them back down into lower ones. Ultimately the space tug got axed and with it went the need for the ability to repair satellites in space since a LARGE portion of Earth orbiting satellites sit higher than Low Earth Orbit. That left shuttle only being able to service vehicles in a very narrow orbit range (Solar Max, Hubble, satellites that had deployment failures etc...). NASA always had a space station in mind as the destination for shuttle from day one, but didn't have the funds to develop both either. But they tried to take more of a "building block" approach this time compared to Apollo's big "winner take all" approach in the budget considerations. George Mueller in the 1960s saw there could be a problem with Apollo as there was no follow up program in the works, which is why he started the Apollo Applications Project, which ultimately became Skylab. But that program got pruned relative to what it could have been as well.

When I look at what the shuttle was, I measure its success not by what its promise was or what its political genesis was. Instead, I measure it primarily by what it could do and what it did. It was a concept that came so COMPLETELY from Science Fiction that its specifications boggled the mind and ONLY the United States of America could build it even though von Braun, Arthur Clarke and even Gerry Anderson dreamed of vehicles like it.

You have an airliner sized orbiter with a massive payload bay strapped to a giant fuel tank and two of the largest Solid Rocket Boosters (something the Soviets never were able to make as even Energia was liquid rocket powered) ever conceived sitting on a launch pad weighing many tons. It goes from 0 to 17,500 mph in an eight and a half minute ride into orbit, spends anywhere from a few days to up to two weeks in the harsh environment of space (changing orbits a bit at a time) before coming back into the atmosphere at mach 25 to bleed off speed and manuever for a controlled landing on an airstrip halfway around the world from where it did its de-orbit burn. And the orbiter than undergoes a turnaround to do it all again in a few months. It could serve as its own self-contained space laboratory with the Spacelab modules, launch probes to the inner and outer planets, dock with space stations and recover errant satellites. It could serve as a stabilizing power supply to vehicles like the early ISS and Hubble while repairs took place in orbit and send up critical logistical supplies to both Mir and the ISS.

Yes, there were deaths, but both Challenger and Columbia were primarily due to very poor management decisions to not look at what the data was telling them about how much of a game of Russian Roulette they were playing with astronauts' lives. Challenger flew after NASA practically flipped their OWN criteria around for declaring a vehicle safe to launch when it wasn't. They way it normally plays out is the contractor says they believe the vehicle is safe to launch and NASA says "we don't think so, prove your case". For Challenger, they didn't though. Columbia was down to management thinking that a critical safety issue (foam shedding) was just a flight turnaround issue and that the TPS could survive foam strikes. Well, the tiles could, but not RCC and they didn't bother to check that after evidence showed something bad potentially had taken place and they tricked themselves into thinking they took everything into account. Both times though, the failure was not with the shuttle orbiter itself, but rather with a part of the SRB in Challenger's case and part of the External Tank in the second case. Challenger probably would have launched successfully if not for the brutal cold of that day, although the SRB field joints (not quite so much the O-rings as they were already doing things they shouldn't have been doing) would still have been a potential time bomb later. After the SRB redesign addressed those issues, there never was a major SRB casing failure in over 100 flights.

All things considered, over the course of 135 flights even factoring in the two losses, I am honestly amazed at how well the shuttle performed as a vehicle. It showed that after the bold steps of Apollo that man could dream bolder and it is almost criminal that the budgets are such that we don't have a good replacement vehicle for the shuttle. Instead, it is back to capsules and plopping into the ocean once again (or a Soyuz trip to Kazakhstan). I have high hopes for Sierra Nevada's Dream Chaser, whose concept is based on the old NASA and Air Force Lifting Body research from the 1960s and NASA Langley's HL-20 concept. I want to see it fly in space and continue the dream of landing men safely on a runway after rocketing into space, while not necessarily having to carry up heavy payloads at the same time. For a vehicle designed less than 100 years after the Wright Brothers first flew at Kitty Hawk and Robert Goddard flew his first liquid rockets, the shuttle was still an engineering triumph. Not bad for our first pass at a reuseable spacecraft. Is there room for improvement, certainly. But I'm not going to damn the whole shuttle on the basis of what it could not or DIDN'T do. Hindsight is only 20/20 afterall.

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You say that it was management that was at fault but not the vehicle. And yet, it was critical areas of the design of the vehicle that caused both major shuttle accidents.

The shuttle could only be flown safely if EVERY aspect of its design weaknesses were properly taken into account by the management. Obviously, the management failed to do this effectively - but the design flaws were there just waiting for management to become sloppy, complacent and negligent.

Indeed, even if management were as disciplined as they possibly could be, I am absolutely convinced that more shuttles would have been lost purely because of the fact that there were far too many "Critical 1" (non-survivable) failures built into the system.

We will never see a vehicle built on these principles again - because there are better and safer ways of doing the various jobs the shuttle was trying to do.

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@JMChladek That's a very interesting perspective. I agree that the achievements have merit but an X-Plane prototype could have achieved all that the shuttle did at far less cost in money, time and lives. Many of those 'achievements' are the result of the compromises I listed, among others. Hindsight is 20/20 but there were plenty of doubts expressed from virtually the first flight. Sadly nothing was done to, apparently, avoid drawing attention to other issues within NASA at the time (Faster, Better, Cheaper ring any bells?)

Eric is, I believe, spot on regarding the engineering aspects. The NASA management WERE responsible for the shuttle design issues and it took a Congressional hearing to make them face up to it. If a car had been released in the same state of development as the shuttle there would have been uproar.

One of the apprentices where I used to work did a project on the Shuttle design (shortly after Challenger IIRC), I was detailed to assist him and was rather shocked with what he found, all in the public domain. He had a pretty good case for an complete failure in every 12 flights, that is, loss of the vehicle and crew. The Engineering Director double-checked his work suggested slightly revising a couple of parameters which got it to about 1 in 18 but decreasing over time. If it was a good system the safety should improve over time as modifications are made in the light of experience. That never really seemed to happen. Most of the post-Challenger recommendations boiled down to 'follow the current procedures and it won't happen again' until it did....

The final nail in the shuttle's coffin for me, was the scramble to get the last ISS components launched on the shuttle riding rough-shod over all the safety evidence. IMHO it was a disgraceful decision to fly it after Columbia when the Russians could support the crew immediately and, probably, launch the last components with a bit of notice. But that would have embarrassed the NASA management and avoiding that was more important than risking lives.

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They say that ALL engineering projects are fulfilled through compromise - and that is undoubtedly true - especially in aviation and space. But I think that the compromises accepted in the Shuttle were just too many and too frequent. And even aspects that NASA originally HADN'T compromised on gradually became compromised through complacency.

Nearly every Shuttle flew with some manager or other waiving at least one launch criteria that should have stopped the launch.

The one great lesson that NASA should learn from the Shuttle is to NEVER run a programme like that again.

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  • 3 weeks later...

The final nail in the shuttle's coffin for me, was the scramble to get the last ISS components launched on the shuttle riding rough-shod over all the safety evidence. IMHO it was a disgraceful decision to fly it after Columbia when the Russians could support the crew immediately and, probably, launch the last components with a bit of notice. But that would have embarrassed the NASA management and avoiding that was more important than risking lives.

What do you mean ride rough-shod? NASA launched TWO return to flight missions that didn't have much to do with ISS construction AT ALL except for sending up logistical supplies. When STS-114 showed evidence of the foam breaking off a PAL ramp, they practically grounded the vehicle another year to get rid of those ramps from the ET and checked out the data before sending up STS-121. After that, the shuttle performed well. The foam breaks after that were at speed ranges and outside the atmosphere so any foam breakage wouldn't have done much and there were plenty of cameras and sensors onboard to inspect the damage sites AND repair/patch capabilities available to utilize should critical damage be detected. Space flight is a dangerous business period. Yes, one should minimize the risks as much as possible. But at the same time ultimately one has to work with the tools one has and the shuttle was both still needed and had corrections made to it to help make it safer.

As far as the Russians potentially being able to finish the ISS by doing their heavy lifting? I don't think so. First of all, after Columbia happened, the next few ISS expeditions had to be reduced from three crewmembers to two because of the need to extend logistical supplies. Yes, the Russians could supply stuff with the Progress craft, but only to certain limits. Onboard recycling of water and waste removal was only just keeping up and there was no way to remove the buildup of clutter onboard as the Progress again was limited in what it could take away to burn up safely. You can't just dump trash overboard in orbit as without precise calculations and orbit selection, that trash could become very dangerous space debris later on.

As for the idea of the Russians being able to even launch the rest of the modules... not really. Yes, they have the Proton rocket and it is a capable launch vehicle. But at the same time, the modules on the US, European and Japanese segments have NO active guidance, onboard thrusters or autonomous docking capabilities. Some sort of tug module was needed. That's a lot like saying "I don't need a moving van for my stuff, I'll just bundle it together, strap a set of wheels, an engine and a steering wheel to it and drive it to my new place myself". I ask you, just how "safe" would that be? Safer than flying the modules the vehicle they were originally intended to fly on?

All the Russian segments flown to Mir and the ISS after the core modules were variations of the Progress or TKS spacecraft designs which had the required systems. Could something have been developed, perhaps. But that takes A LOT of time and effort and there is no guarantee it would have worked. Contrary to popular belief, the Russian manned space program was still rather cash strapped in the late 1990s and early 2000s. They didn't even have the money to build a backup Russian service module core for the ISS. The core they used for the RSM was technically the Mir 2 model, built originally as a backup to Mir during the Soviet days. It took A LOT of funding from NASA for the Russians to even convert it for use as the core of the ISS and quite a bit of that money was funneled away in the process to things that did not have anything remotely to do with space hardware (such as building houses for retired Russian military officers and heads of the space program, partly because their pensions became worthless when the Soviet and Russian economies tanked).

Say they even managed to get modules up that way and say this bodged together contraption was able to dock properly (not to mention safely). Okay, what then? The SSRMS (or Canadarm II) wasn't even fully operational when Columbia burned up and even then there were a limited number of places it could go on the structure. You also need dedicated spacewalker support as well to dock the modules, remove launch locks and hook up all the coolant lines and hook up the data cables outside. But wait, we still only have TWO crewmembers onboard due to logistical issues. Are they going to do these tasks alone? Do you launch more Soyuz craft with dedicated spacewalkers to do the job? Don't forget the tools and that is going to add more weight to the mix. Shuttle could do it. Oh wait, it's grounded... can't fly it because we don't want to be perceived as being "rough-shod" on safety.

Like it or not, shuttle was the ONLY vehicle available that could have helped finish ISS construction, not just because of the modules it carried up and the dedicated spacewalker support from typically about half a given shuttle crew (four people, working in two person teams on alternating days), but also because of the Italian space agency's Multi-Purpose Logistics Modules (MLPMs) carried into orbit by the shuttle. Many of the shuttle missions involved sending up these MLPMs to send up a HUGE amount of supplies needed internally. They are like moving vans and they could haul A LOT more than what the Progress craft could. Eventually when ESA's ATV started flying, it took over a lot of the heavy lifting, but there were limits as to what it could carry. More importantly though, the MPLMs also brought a lot of no longer needed equipment back, which reduced the internal clutter. Part of the reason why the ISS can potentially operate for another 6 to 10 years is because of the equipment that was stockpiled onboard from those shuttle delivered MPLMs. One of the MPLMs got converted for use into a PLM (permanent logistics module) for storage of items, something that could not have been done if it hadn't been brought back after its final MPLM mission.

The shuttle also had an excess of fresh water generated by its fuel cells (something the ISS does not use). Water is a very important item in any space vehicle, be it used for drinking or electronics cooling. Today the ISS has water recycling capabilities. Back then, not quite so much and regular infusions of water from shuttle missions were required. They were also a VERY key componant of why the Mir station kept flying for as long as it did as every Shuttle Mir mission brought up A LOT of well needed water, as well as electrical power generation for when the vehicles were docked AND atmospheric scrubbing capability that didn't necessarily require those oxygen generating canisters (like the one that caught fire on Mir and nearly caused a disaster).

Even if you disregard all that, shuttle's final contribution to ISS assembly was as a worksite platform. That big payload bay in addition to whatever module it was bringing up also carried all the tools and support equipment needed for the assembly. Plus it also had the Canadian RMS acting as an assembly crane of sorts. On a few of the later missions, the SSRMS did more of the heavy lifting, but the RMS was still needed to hand off the modules.

And I almost forgot... that Orbiter Boom Sensor System arm segment developed for imaging the shuttle's bottom came in REALLY handy on STS-120 when one of the solar arrays got snagged on re-deployment. That particular array had been unfurled on top of the ISS for a few years longer than originally intended (because the Columbia accident grounded the shuttle program and delayed ISS assembly) and when it was moved and re-deployed, the guide wires frayed and started tearing the solar panels. The array couldn't be left like that in a partially unfurled state as it would have been unstable during thruster firings. So what did the combined shuttle and ISS crews do? Those ten people (not two or three) spent time with help from the ground coming up with a fix. Two of the best spacewalkers in the business then went out and using the SSRMS with the OBSS boom went to the worksite and installed the cufflinks to bypass the guide wires in that section. The OBSS was needed since the SSRMS was not designed to go that far out. The shuttle was also needed to provide a better visual vantage point to what was going on outside as well. The result was a successful fix and a saved space station. If that array had to be jettisoned and abandoned, it would have crippled the ISS's power generation capabilities.

I realize I am not likely to change anyone else's mind if they already have it in their head that shuttle was a "failure". But I will say that the ISS most certainly could NOT have been completed without the shuttle doing its share and extended Russian involvement would not have changed that. The shuttle from day one was practically designed to help assemble and service space stations and when it did that job, it delivered in spades. It was a combination of lorry, coach bus, mobile work site, construction crane, portable living quarters, latrine, galley, air conditioning and trash truck all rolled into one package.

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The Shuttle HAD to be used to construct the ISS because it was the only heavy lifter available to do the work. That is called "Hobson's Choice" - you go with what you have, not because it is "good" but because it is "only".

After Columbia, NASA made a decision to only fly the Shuttle on ISS supply and build missions. They essentially stuck to that decision but re-instated the cancelled last Hubble repair flight when put under pressure by the astronomical community.

Of course the Shuttle did great things during its 30 years of operation. But it didn't achieve all the things it had set out to do and the launch rate fell woefully below what had been anticipated.

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  • 4 weeks later...

What I mean by ride 'Rough Shod' is exactly what you mention. 2 ships lost with all crew, but the 'need' to repair Hubble to keep NASA's credibility meant that flight was scheduled. I wonder if the 'need' would have been so great if it was crewed by the management who decided it was OK to go? No, of course it wouldn't.

I did state that 'a bit of notice' would be required to finish the ISS without the shuttle. I refuse to even consider that it would be impossible for the Russians to launch the components unless we're talking politically.

That the shuttle did as well as it did is a credit to the designers, engineers and crew who did as well with it as they did despite the management decisions taken from the beginning. The ISS was designed around the shuttles capabilities so it should do well. But remember Skylab offered much greater internal volume and was launched in one go 30 years ago!

The question asked was whether it was good or bad for NASA. My position is that it was bad, I don't consider it a complete failure but believe that many of the gains could have been achieved in other ways with better safety and much lower cost. The fundamental soundness of a capsule re-entry and single use of same is obvious from the current NASA proposals that look remarkably like Apollo hardware on steroids and the Earth/Moon Orbital Rendezvous of a two launch component mission.

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And I am sure with a bit of thought and ingenuity, a lot of the "capsule/booster" combination can be made reusable too. The Orion capsule will be reusable for a start.

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Yes Eric - the boosters are already recoverable, and while it would be a problem getting the entire core stage down in one piece ( unless SpaceX figure it out ) there's always the option of ejecting the engines in a recoverable pod

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