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The rise and fall of NASA’s Shuttle-Centaur

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  • 09-10-2015 10:24pm
    #1
    Closed Accounts Posts: 3,006 ✭✭✭


    In January 1986, astronaut Rick Hauck approached his STS-61F crew four months before their mission was scheduled to launch. The shuttle Challenger was set to deploy the Ulysses solar probe on a trajectory to Jupiter, utilizing a liquid-fueled Centaur G-Prime stage. While an upcoming launch should be an exciting time for any astronaut, Hauck's was anything but optimistic. As he spoke to his crew, his tone was grave. He couldn't recall the exact quote in a 2003 Johnson Space Center (JSC) oral history, but the message remained clear.

    “NASA is doing business different from the way it has in the past. Safety is being compromised, and if any of you want to take yourself off this flight, I will support you.”

    http://arstechnica.com/science/2015/10/dispatches-from-the-death-star-the-rise-and-fall-of-nasas-shuttle-centaur/#p3


    I haven't got through all of it yet but NASA are were a careless shower.


Comments

  • Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 91,408 Mod ✭✭✭✭Capt'n Midnight


    The whole thing was crazy. Centaur had already been boosted to orbit by Atlas and Titan before. There was no need to use the shuttle. Hydrogen is the second leakiest substance known, the original Centaur was only rated for 30 minutes in orbit, the later ones extended that to few hours, we aren't talking about storable propellants here.


    https://en.wikipedia.org/wiki/Centaur_%28rocket_stage%29
    From 1966 to 1989, the Centaur-D was used as the upper stage for 63 Atlas rocket launches. 55 of these launches were successful
    ...
    In 1975, Titan-Centaur launched the Viking 1 and Viking 2 spacecraft to Mars
    ...
    The following two launches were the Voyager 1 and Voyager 2 spacecraft
    ...
    The Centaur, as carried in the Shuttle payload bay, required a complex airborne support system, the Centaur Integrated Support System (CISS). The CISS controlled Centaur pressurization in flight and enabled Centaur's cryogenic propellants to be dumped overboard quickly in the event of an abort. Shuttle-Centaur flights would have run the Shuttle's main engines at 109%, higher than the typical 104%, and the Shuttle would have had to orbit at its lowest possible altitude.

    The whole shuttle concept was flawed as it was sized to handle the largest Air Force Spy Satellites. So the take off weight was 2,000 tonnes. By comparison Soyuz is a little over 300 tonnes.

    In theory the shuttle was reusable but it took 25,000 people to do it so labour costs were $1Bn a year

    The boosters had O rings because they were made from road transportable segments so they could be made in the middle of nowhere.
    https://en.wikipedia.org/wiki/PEPCON_disaster



    The shuttle was more expensive than it would have been to have kept using the stuff that existed in the 1970's
    http://aviationweek.typepad.com/space/2007/03/human_space_exp.html year.  This entire program of six manned flights per year, two of them to the Moon, would have cost about $6.3 billion annually in Fiscal 2000 dollars. ... we would have continued to modify, refine, and incrementally improve the old Apollo designs, to the point where they would have provided greatly enhanced effectiveness by the present day.  If we had done all this, we would be on Mars today, not writing about it as a subject for “the next 50 years.”

    The ISS weighs about 420 tonnes. (mass whatever) So 4 Saturn V launches.

    It should be noted that the Russians have the experience in long term space flight. Mir lasted almost 10 years , the ISS is totally dependent on the Russians. For the US the ISS is a way to learn what the Russians know. Despite the KISS principle, the US used ammonia on their part of the ISS. Yes it's lighter and more efficient, but the Russian's used anti-freeze which isn't as toxic and AFAIK didn't need as many repairs.


  • Moderators, Social & Fun Moderators Posts: 12,734 Mod ✭✭✭✭JupiterKid


    The Shuttle may have looked great but it was deeply flawed. Using it for as many launches as possible of deep space probes was ridiculous. And it was rather dangerous - 2 fatal disasters in about 130 flights.

    And now NASA are revisiting Apollo heritage for its next generation manned launch system.


  • Registered Users Posts: 34,706 ✭✭✭✭Hotblack Desiato


    All down to funding. The pork barrel has to visit as many states as possible (and as you mentioned, this is what led directly to the Challenger disaster.) It's easier to get funding for a new project that can spread the pork around to new places than it is to keep an existing one going.

    NASA had to get into bed with the USAF for funding reasons and that led directly to the Columbia disaster. The only justification for the shuttle having large wings was the military polar orbit, once-around mission.

    But there really wasn't justification for the shuttle at all. The Soviets put Soyuz on a production line and that's what NASA should have done with Apollo CSMs and Saturn IBs.

    Fingal County Council are certainly not competent to be making decisions about the most important piece of infrastructure on the island. They need to stick to badly designed cycle lanes and deciding on whether Mrs Murphy can have her kitchen extension.



  • Registered Users Posts: 11,174 ✭✭✭✭Captain Chaos


    JupiterKid wrote: »
    The Shuttle may have looked great but it was deeply flawed. Using it for as many launches as possible of deep space probes was ridiculous. And it was rather dangerous - 2 fatal disasters in about 130 flights.

    And now NASA are revisiting Apollo heritage for its next generation manned launch system.

    2 fatal disasters that were known about and NASA said feck it both times, gambled and lost. Both were preventable and known about before they happened.


  • Registered Users Posts: 883 ✭✭✭Keplar240B


    ......................................

    But there really wasn't justification for the shuttle at all. The Soviets put Soyuz on a production line and that's what NASA should have done with Apollo CSMs and Saturn IBs.

    Is there anything it did that would have been impossible otherwise.

    Hubble for example?


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  • Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 91,408 Mod ✭✭✭✭Capt'n Midnight


    2 fatal disasters that were known about and NASA said feck it both times, gambled and lost. Both were preventable and known about before they happened.
    There was also the totally preventable Apollo 1


  • Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 91,408 Mod ✭✭✭✭Capt'n Midnight


    Keplar240B wrote: »
    Is there anything it did that would have been impossible otherwise.

    Hubble for example?
    Hubble cost €2.5Bn to build. Original estimate was $400m

    Each shuttle launch cost about $1.45Bn. So just maybe in this case it saved a billion dollars. But if they'd actually tested Hubble before launching then they would have spotted the problem caused by that fleck of paint. So no real saving.


    The delays in the shuttle program are what killed Skylab. And it's telescope. https://en.wikipedia.org/wiki/Apollo_Telescope_Mount

    The shuttle leaked oxygen so had a limited time in orbit. A lot of the experiments and observations could have been done in Skylab.

    All the satellite launches could have been done with Saturn I / Titan / Atlas as many were later.

    In spite of the many visits to the Mir and ISS all of the long term crews went by Soyuz. Cargo to the ISS was also carried out by Japan , Russia and ESA.

    AFAIK the shuttle only returned ONE satellite. Much like the F35 "one size fits all" an awful lot of money could have been saved by using several smaller craft sized to their task

    In a nutshell the economics of the shuttle required weekly/fortnightly launches of 10-20 tonne payloads. The demand just wasn't there.



    The Russian Shuttle was flown on auto-pilot and so didn't risk crew live on maiden flight. The Energia system could also be used to launch other 100+ tonne loads. ( or more with 8 boosters ) The boosters are still in use as Zenit .


    Google Dynasoar to see what might have been.


  • Closed Accounts Posts: 3,006 ✭✭✭_Tombstone_




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