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Next NASA Vehicles To Resemble Shuttles

Posted by Zonk on from the stick-with-a-good-thing dept.

ausoleil writes "Spaceref.com has an internal NASA memo outlining potential plans for the next generation of launch vehicles. They will closely resemble the current Shuttle and use some of the same hardware. Of course, they plan to leave the exploding parts out of their next versions. From the article: 'NASA has decided to build two new launch systems - both of which will draw upon existing Space Shuttle hardware. One vehicle will be a cargo-only heavy lifter, the other will be used to launch the Crew Exploration Vehicle.'"

8 of 205 comments (clear)

  1. Nice to see an Ares stack finally getting props by rossifer · · Score: 5, Informative

    This memo could be a photocopy of something circulating thirty years ago. Sounds like they're finally going to take advantage of the modular parts of the shuttle the way they talked about when the shuttle stack design was being originally being funded twenty-five to thirty years ago. One nice change is that the rumor mill believes the heavy lift stack bears a striking resemblance to Robert Zubrin's Ares stack (a.k.a. Shuttle-Z).

    The "Shuttle-C" cargo stack (and variations) were originally publically discussed in the early '80s as reasons why the shuttle was worth all we were spending (you don't just get the shuttle, you also get a "normal" heavy-lift launcher). Those variants, however, have had problems that could only be resolved by massive cultural change at the NASA level. One of the biggest issues was payload capacity of the side-slung configuration. Since then variations including the Ares stack and the more recent Shuttle-B have appeared and pretty much gone nowhere.

    I suspect that the United Space Alliance's (USA's) "risk averse" culture will actively hinder and ultimately frustrate all of these plans. If you've ever worked for a government contractor, you'll understand the culture I'm talking about. They (Boeing and Lockheed-Martin, the companies in the USA partnership) don't have to compete in markets, and are positively allergic to any hint that they may have to compete with other companies for revenue. If NASA's hoping for bargains, they won't find them when dealing with USA.

    Regards,
    Ross

    1. Re:Nice to see an Ares stack finally getting props by skyman8081 · · Score: 2, Informative

      It was called the X-20 "Dyna Soar". It was canceled in 1963, one prototype that was not capable of flight was ever built.

      --
      Two Roommates and a Boyfriend, updates Monday, Wednesday, and Friday
  2. SRBs not SSMEs! by mikejz84 · · Score: 5, Informative

    Overall, not a bad idea--it will be a Saturn V class booster. I am not crazy about using 6 SSMEs however, they are designed to be reusable, not flown on an expendable booster and are expensive as hell (about $300 million for the 6 first stage engines alone) Also, I seems to only speak of using 2 SRBs in the in-line HLLV, it would seem to me to make more sense to use 4 or 6 clustered around the core. After all, the shuttle SRBs are some of the cheapest power you can get.

    1. Re:SRBs not SSMEs! by DerekLyons · · Score: 2, Informative
      It may have been there intention to make the SSMEs reusable but from what I read in the original Feynman report
      [frustrated sigh] You do realize that the Feynman report was written nearly twenty years ago?

      The frustrated sigh is because of people who keep quoting that damm report and act as if the Shuttle is stuck in some kind of time warp. The amount of utter ignorance on Slashdot about the Shuttle amazes and frightens me... Here's an incredible ongoing engineering feat with tons of information available on it - and everyone quotes from a twenty year old document as if it were written yesterday.

      they were designed so close or past the engineering of the time that they had to be completely rebuilt after every flight anyway.
      That was true then, but this is now. They stopped rebuilding them after every flight about 1989 or so, and stopped pulling them for inspection after every flight about 1995 or so. The current Block II SSME's are a considerable improvement in performance and reliabilty over the Challenger era ones.
    2. Re:SRBs not SSMEs! by ciroknight · · Score: 2, Informative

      It's okay you're not okay with the idea. The engines are only being used now because the current space shuttle uses them. If you really want to think about it, all they have done is strip the wings off the shuttle, stuck the shuttle on top of the liquid fuel tank, and taken two shuttle engine packages and stuck it to the bottom. Nothing more than an out of box reconfiguration of the parts, hardly nothing new has to be constructed, and all of the surplus shuttle parts get used. Not to mention it allows them to move on to more complex configurations such as 3 SRBs or 4 SRBs, or how ever many they can squeeze around that liquid fuel tank in the center with engineering feasability.

      Don't worry about it.. This step is all about phasing out the parts of the space shuttle program that just didn't work. The whole "flight to recovery" step just didn't work, so they're stripping the wings off the shuttle. The whole "riding the back of the booster" instead of on top just didn't work, so they're stripping that away. The overall package becomes a hell of a lot more aerodynamic, cheaper to manufacture (other than the refit of the buildings to deal with something taller than the Saturn-V, which in it's own way is exciting and revolutionary), and cheaper to put things in space.

      --
      "Victory means exit strategy, and it's important for the President to explain to us what the exit strategy is." G.W.Bush
  3. What's old is new again by AKAImBatman · · Score: 5, Informative
    The Crew Exploration Vehicle is certainly nothing new. Nor am I surprised by NASA's desire for a more powerful booster. It is, however, good to see NASA again contemplating super boosters. While many people feel that such boosters are useless (hi Rei!), there are certain circumstances under which they can be tremendously useful.

    Take the case of SkyLab vs. the International Space Station. According to Wikipedia, the two stack up as follows:
    Mass:
    SkyLab: 77,088 kg
    ISS: 419,000 kg (when completed; currently 183,283 kg)

    # of Lauches for complete construction:
    SkyLab: 1
    ISS: 50 (39 Shuttle flights)
    Now with some simple math, we find that SkyLab averaged 77,088 kg per launch which the ISS averages about 8,380 kg per launch.

    If you didn't just do a double take, you should have. The booster that lifted SkyLab stuck over 9 times the mass into orbit that current ISS flights do! Just what is going on here?

    The answer lies in the Saturn V Booster vs. the current Space Shuttle. A three stage Saturn V had a maximum payload of 118,000 kg. (That's enough to send the entire ISS up in only 4 flights.) The Space Shuttle, OTOH, only has a cargo of 28,800 kg to LEO. So why does NASA want to reuse the tech? Because of the weight of the shuttle itself.

    The Space Shuttle orbiter weighs in at a whopping 104,000 kg! Combined with its cargo capacity, the Space Shuttle is capable of 132,800 kg to LEO! That's way more than the Saturn V could manage on all three stages. So if we ditch the orbiter itself, the shuttle's infrastructure could be the most powerful superbooster ever designed.
    --
    Javascript + Nintendo DSi = DSiCade
  4. Re:Do We Have To Keep Carrying Our Fuel With Us? by dabigpaybackski · · Score: 2, Informative
    Don't forget about these people. Skyramps were Werner von Braun's original idea for putting things into orbit. Arrayed against him were the USAF, who favored vertically-launched rockets because they could quickly be fired off in annihillating volleys at the Soviets, and probably the rocket manufacturers themselves, who stood to make far more money from vertical-launch than from von Braun's more efficient method.

    Check out the site. It's full of fascinating stuff.

    --
    "OH SHIT, THERE'S A HORSE IN THE HOSPITAL!"
  5. Re:a rocket? by everphilski · · Score: 2, Informative

    detla-V = g*Isp*ln(m1/m0)

    where:

    delta-V = 7600 m/s for LEO (a little more for space station)

    g = 9.8 m/s^2 (gravity)

    Isp = 295-450 1/s (Specific Impulse, basically a thrust rating of a propellant. 295 for a solid in a vacuum, 450 for a SSME in a vacuum. Lower on the surface of the earth)

    m0 = takeoff mass

    m1 = mass on orbit

    Play around with the numbers. You will find out quickly that single stage to orbit with any significant amount of payload is ... hard. And this doesn't include mass requirements for coming home: retro-rockets, wings and landing gear or parachutes and more rockets, etc.

    Until some material advances are made (mass ratio, m1/m0 can be imrpoved) or nuclear propulsion can be considered an acceptable option (The technology exists: Isp = 800-900) single stage to orbit with any more than 1-3 human beings will be a difficult feat.

    Staging alleviates the problem. Check out Sutton's Rocket Propulsion Elements or Hill & Peterson's Mechanics and Thermodynamics of Propulsion.

    Re-using existing technology is the quickest, cheapest, easiest way to get back in business. I think it's a pretty good idea.

    IAAAE (I am an Aerospace Engineer)

    -everphilski-