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Space Science

Moonshot, CEV Modifications 108

Posted by ScuttleMonkey from the falling-back-on-pre-1970-tech-is-always-the-answer dept.
DarkNemesis618 writes "In the latest round of budget cuts, NASA introduced plans to modify the CEV for the planned Moon landing in 2018. The original plan called for an engine used on the space shuttle to be modified for the CEV. The new plan is to use an updated J-2 engine. The J-2 engine was first used on the Saturn V rocket which took the Apollo astronauts to the moon in the late 60's early 70's. It is not expected to save any money in the near-term, but in the far term, it should be a cost saver since the technology already exists and is proven. In the 10 Apollo launches aboard the Saturn V rocket, there were no problems with the launch vehicle."
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Moonshot, CEV Modifications More

Moonshot, CEV Modifications

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  • Comment removed (Score:4, Interesting)

    by account_deleted ( 4530225 ) on Wednesday February 01, 2006 @04:15PM (#14619880)
    Comment removed based on user account deletion

    • Re:Let's see... (Score:2, Insightful)

      by 2.7182 ( 819680 )
      Here's the thing though: It worked 10 times. So what ? The space shuttle worked safely 24 times before it had a problem.

      BTW there are 2 or so Saturn V still lying around to use- see here [wikipedia.org]

      • Re:Let's see... (Score:4, Insightful)

        by SnowZero ( 92219 ) on Wednesday February 01, 2006 @04:33PM (#14620107)
        The shuttle engine is not currently capable of in-air ignition, while the J-2 engine did exactly that for Apollo. The shuttle engine would thus have to be modified, while the J-2 engine would not. So it's more like 10 times vs 0.

        P.S. This is pretty clearly written in the article.
        • That's not my point. What I meant is that just because it worked 10 times doesn't mean it is "proven". Ten is a small number of trials. I am not saying the Shuttle engines should be used.

          • Re:Let's see... (Score:3, Informative)

            by AKAImBatman ( 238306 )
            The Saturn 1B flew an addition 10 flights on the J-2s, which was based on the Saturn 1 that flew 10 flights on the RL-10s, which was based on the Jupiter IRBM that flew about 17 flights. Each Saturn 1B had 1 J-2 while each Saturn V had 6 J-2 engines.

            Or in other words, the J-2 engine has a long history and has proven itself highly reliable. Its reliability isn't really in question.

        • Unless we're talking about a shuttle engine that I'm not familiar with, the three main shuttle engines do burn in the air. They provide the balance and thrust from initial ignition until SRB seperation.

          The also continue burning into orbit. They don't stop burning until just before the external fuel tank is dropped.

          For easy proof, watch most launch videos. They usually show the engines fire up. You can usually see the entire launch vehicle tilt as soon as they
          • Unless we're talking about a shuttle engine that I'm not familiar with, the three main shuttle engines do burn in the air.

            They are ignited on the ground, and ignition depends on ground infrastructure. In-flight ignition would require engine modifications, and that is why the J-2 is an attractive alternative -- while its performance is lower, the engine is far simpler and specifically designed for in-flight startup.

      • Re:Let's see... (Score:1, Informative)

        by Anonymous Coward
        Yes, but the shuttle's engines only worked 19 times before one of them failed in flight. And only a fast thinking controller prevented a second engine from also shutting down, which was a very good since the Shuttle would of probably ended up in the middle of the Atlantic if a second SSME had gone down.
      • BTW there are 2 or so Saturn V still lying around to use
        Niether of those Saturn V's have their instrumentation unit, and niether of them is anywhere near in a condition to be launched.

    • Re:Let's see... (Score:2, Insightful)

      by DisownedSky ( 905171 ) *

      The SSME is tricky beast. Converting a slightly more modern (30 year-old) but very large and complex lower stage engine vs. reviving an older upper stage design. They will re-design this engine somewhat, but they know the basic design works in the intended role.

    • What you're not getting is the time, money and risk of debugging a new design.

      The other point is that the SSME was never designed to be started at altitude.

    • Re:Let's see... (Score:2, Insightful)

      by Anonymous Coward
      Modify a less-efficient, 40 year old design that hasn't been produced in several decades, or modify a more-efficient currently-used design. Choose the former because it "already exists?"

      It's not quite a simple as that.

      True, the J-2 is older and less-efficient, but it's a much simpler, more reliable design than the SSME.

      The SSME is much more intricate, tempermental, expensive and operates at much, much higher pressures than the J-2. The reliability of the SSME in the Shuttle is more a tribute to the army of
      • True, the J-2 is older and less-efficient, but it's a much simpler, more reliable design than the SSME.

        The SSME is much more intricate, tempermental, expensive and operates at much, much higher pressures than the J-2. The reliability of the SSME in the Shuttle is more a tribute to the army of inspectors employed by NASA than to its inherent design.

        Personally, if I were trusting my life to a new rocket , I'd prefer to sacrifice a little ultimate efficiency for an engine that has reliabilty designed in, not i

    • Re:Let's see... (Score:5, Informative)

      by Burdell ( 228580 ) on Wednesday February 01, 2006 @04:34PM (#14620123)
      The SSME is higher efficiency in terms of thrust vs. mass. However, that isn't the only measure to be considered. Each SSME costs a lot more to build, because they were designed to be reused (IIRC the current plan is to not reuse the new vehicle's engines). The SSME is throttleable, but if that is not needed, it is an added complexity and expense. The J-2 was designed to be throw-away.

      Also, there are some questions about the SSME for the new vehicle. The SSME would be used in upper stages that are lit in-flight. The SSME has only ever been lit sitting still, on the ground, at sea-level atmospheric pressure and temperature. The J-2 was used on upper stages of the Saturn V, so it is proven in that capacity.
      • Yeah, the main reason cited for choosing a J-2 over the Space Shuttle Main Engine (SSME) is that the J-2 was always air lit, as the 2nd and 3rd stages of the Saturn V (the first stage used 5 F-1 engines).

        However, I believe that the SSME is also lit in orbit, for the de-orbit burn, and possibly for orbit changing maneuvers (like when a space junk collision is likely). When lit in space, it uses fuel from 3 onboard fuel tanks rather than the big orange tank used for take off.

        I guess the difference there is th

        • Re:Let's see... (Score:3, Informative)

          by Burdell ( 228580 )
          Nope, you are wrong. SSMEs are lit on the pad six seconds before liftoff. They burn for about 9 minutes and then shut down for the rest of the flight. The SSMEs are fueled by liquid hydrogen and liquid oxygen stored in the big orange external tank, which is discarded right after SSME shutdown (so the rest of the flight there isn't any fuel for the SSMEs). The next time an SSME would be lit is after removal from the orbiter, refit, and either at a test facility or at another launch.

          Orbital maneuvering is
          • OK, and the OMS nozzles are the nozzles who's size is in between the big SSME bells and the small RCS nozzles, which are mostly hidden away. (Do I have this right?)
            • Yes. Looking at the back end of the orbiter, the SSMEs are the three largest engines. Above them, on either side of the tail, are the two OMS engines. Then there are small RCS nozzles in various places around the nose and tail of the orbiter (IIRC there are 38 primary and 6 secondary RCS engines).

              The SSMEs get you to orbit, the OMS change orbits and get you out of orbit, and the RCS point you where you want to look.

            •     If I remember right:

                  OMS = Orbital Manuvering System
                  RCS = Reaction Control System

                  RCS are almost always automatically firing to keep the attitude of the orbiter correct. OMS are used for manuvering, such as to roll over for re-entry or to manuver for satellite deployment or docking.

    • Mainly, the SSME is incredibly complex and expensive ($40m). Even though it has vastly higher power density than the J-2, sometimes less is more.

      I wish I could find parts counts for both the J-2 and SSME, but the good old days when I had all this info in Dead Tree Edition are long gone.
    • Not sure how much "less-efficent" the J-2 is.

      http://www.astronautix.com/engines/ssme.htm [astronautix.com]
      Manufacturer Name: RS-24. Designer: Rocketdyne. Developed in: 1972. Application: . Propellants: Lox/LH2 Thrust(vac): 232,301 kgf. Thrust(vac): 2,278.00 kN. Isp: 453 sec. Isp (sea level): 363 sec. Burn time: 480 sec. Mass Engine: 3,177 kg. Diameter: 1.63 m. Length: 4.24 m. Chambers: 1. Chamber Pressure: 204.08 bar. Area Ratio: 77.5. Oxidizer to Fuel Ratio: 6. Thrust to Weight Ratio: 73.1197829645898. Country: USA. Status:

  • Not really a surprise (Score:5, Informative)

    by AKAImBatman ( 238306 ) <akaimbatman@ g m a i l . com> on Wednesday February 01, 2006 @04:21PM (#14619960) Homepage Journal
    Note that this isn't really a surprise to those who have been following the CEV development. The original plan called for a modification to the SSMEs for multiple restarts as the J-2 (the upper stage engine for the Saturn V) is no longer in production. However, there was a lot of discussion inside NASA that restarting production on the less powerful J-2 would be cheaper, faster, and easier than trying to modify the more powerful (but far more complex) SSME to do the job.

    To give quick rundown on which engines are which:

    SSME (Space Shuttle Main Engines) - LHOx Fuel - 1.8 MN
    SRB (Solid Rocket Booster) - Solid Fuel - 14.7 MN
    J-2 (2nd and 3rd stage Saturn V) - LHOx - 890 kN
    F-1 (1st stage Saturn V) - Kerosine - 6.7 MN

    The SSME and J-2 are directly comparable, and the SRB and F-1 are directly comparable.
    • Which makes me wonder why not use the F1 instead of the SRB.
      • Did you see those differences in performance on those engines? The SSME is about twice as powerful as the J-2, but it also weighs twice as much. Thus it makes sense to use two J-2s. The SRBs OTOH, get over twice the power of the F-1 for far less weight. Since they're almost entirely fuel (not much engine, just light 'em up), they have an incredible thrust to weight ratio.

        In addition, NASA has no infrastructure for Kerosine fuels, making the switch from the SRBs to the F-1 more difficult. They *do* have an i

        • Re:Not really a surprise (Score:4, Informative)

          by LWATCDR ( 28044 ) on Wednesday February 01, 2006 @04:56PM (#14620404) Homepage Journal
          "In addition, NASA has no infrastructure for Kerosene fuels,"
          Atlas V?
          Also what is the specific impulse for an F1 first stage VS an SRB?
          Yes the SRB has more static thrust but I think the F1 is equal to it in specific impulse. Plus the F1 allows for an on pad shut down and is probably easier the vector than an SRB.
          BTW the Specific impulse for the SRB is 268.8 For the F1 it is 304.8.

          Using modern AlLi alloys for the tanks an F1 powered first stage might still be a good option. The real reason is cost. The SRBs are cheaper short term.
          • Surely if the use is initial liftoff the important statistic is thrust to weight ratio. The question of efficiency -- which is what specific impulse measures -- seems rather secondary, unless I'm missing something. An ion engine, for example, would have a far greater specific impulse than either chemical engine, but since its thrust is so pathetic it couldn't get itself off the ground.

            To put it in plebian terms, if you need to outrun the cops (i.e. achieve escape velocity), surely it's better to be drivin
            • But you have to carry the fuel as well. The the thrust of the main engine must both lift it's self. the payload, and the fuel. Your example is an extreme example. For a liquid fuel launch vehicle the ideal thrust to weight ratio at launch is close to 1.1:1 any less and the thing is not going anywhere and more and you are not using the vehicle to it's maximum potential. You could put more fuel and go higher and faster or more payload to the same orbit. Yes you would also have to carry more fuel as well but y
              • But you have to carry the fuel as well.

                Right. That's why I said thrust to weight ratio, i.e. thrust divided by weight. For the SRBs, it's enormous. Not so for the other engines. The fact that the SRBs don't squeeze as much energy out of their fuel seems rather beside the point. Fuel efficiency isn't the name of the game when you lift off, raw acceleration is -- yes?

                That's why I suggested the comparison to the Dodge Viper vs the Toyota Prius. The Viper gets crappy gas mileage compared to the Prius, of
                • That's why I said thrust to weight ratio, i.e. thrust divided by weight. For the SRBs, it's enormous.

                  Just some numbers to help you out:

                  SRB Liftoff: 14,700 kN / (590,000 kg * 9.807) * 1000 = 2.5:1 ratio
                  SI-C Liftoff: 33,400 kN / (2,280,000 kg * 9.807) * 1000 = 1.5:1 ratio

                  Of course, there's a huge curve in thrust-to-weight between the full and empty rockets (with the S-IC actually coming out ahead at empty), but I'm willing to bet that the plotted curves would show the overall power output of the SRB to be f
                  • "Where do you think he gets this nonsense about a 1.1:1 ratio? A rocket would never make orbit with that kind of performance! (Putting aside the fact that it would topple over and blow up on launch.)"

                    Wow you don't really get it do you? That is at launch. As fuel is burned the rocket will get lighter.
                    Acceleration ISNOT important for a launch vehicle except during the transonic region of flight. At that time your drag goes way up and actually drops once you get to supersonic flight.. All acceleration does is
                    • Wow you don't really get it do you? That is at launch. As fuel is burned the rocket will get lighter.

                      No, everyone here but you gets it. If the rockets were launched in a vacuum, you'd be right. But for a launch, you're completely ignoring the factors of Gravity Drag [wikipedia.org], Aerodynamic Drag [wikipedia.org], and Engine Efficiency. Which is downright laughable since you mention the engine efficiencies as if they support your point!

                      You MUST get the rocket above the effects of aerodynamic drag as quickly as possible, otherwise you're
          • "In addition, NASA has no infrastructure for Kerosene fuels,"

            There have been a handful of Atlas V launches. Nothing near the scale of what the Shuttle flys today, and what the CEV *will* fly.

            Yes the SRB has more static thrust but I think the F1 is equal to it in specific impulse.

            Static thrust is what you want. The point of the F-1s and SRBs was to get the rocket off the pad, up to Max Q, and out of the thickest part of the atmosphere. From there the more efficient LHOx engines provide more than enough thru
            • "There have been a handful of Atlas V launches. Nothing near the scale of what the Shuttle flys today, and what the CEV *will* fly."
              What are you talking about? The shuttle flew 12 times a year at it's peak? The CEV will fly maybe that many? The Atlas V is going to be used for commercial and military launches for how many years?
              I also do not believe that the F1+Fuel is much heavier then an SRB. The difference in the specific impulse means close to 10% less fuel mass for the F1 than the SRB.
              Without a complete
              • What are you talking about? The shuttle flew 12 times a year at it's peak? The CEV will fly maybe that many?

                And the Atlas V has flown only 7 times in the past 3.5 years it's been in operation. Plus it's not even NASA's rocket. They've flown it twice, with the other flights being entirely commercial. The future planned flights will be mostly military and will attempt to move the launch to Vandenberg.

                I also do not believe that the F1+Fuel is much heavier then an SRB.

                Saturn 1C Empty: 135,218 kg
                SRBx2 Empty: 174

                • Re:Not really a surprise (Score:3, Informative)

                  by AJWM ( 19027 )
                  Saturn 1C Empty: 135,218 kg
                  SRBx2 Empty: 174,000 kg
                  Saturn 1C Fueled: 2,286,217 kg
                  SRBx2 Fueled: 1,180,000 kg

                  That's not quite an apples-to-apples comparison. Initial thrust of the 2 SRBs is about 5 million pounds, of the S1C, about 7.5 million pounds. The Shuttle launch is also augmented by the thrust of the 3 SSMEs, and the whole thing puts about 65,000 pounds in orbit. The Saturn lower stages (S1C followed by SII) could put about 200,000 pounds in orbit.

                  The 2 SRBs don't have quite the same thrust as the 5
                  • Initial thrust of the 2 SRBs is about 5 million pounds

                    Where do you get 5 million pounds? I have 3.3 million pounds of force per SRB, giving a combined total of 6.6 million pounds of force, or 29.4 kN. That's pretty darn close to the 33.4 MN of the S-IC.

                    Shuttle launch is also augmented by the thrust of the 3 SSMEs

                    This is where we start getting into the fact that the Shuttle is just different. The total STS power on liftoff is OVER the standard 34.8 MN of all the engines combined (the SSMEs are overthrottled

                    • Re:Not really a surprise (Score:3, Informative)

                      by AJWM ( 19027 )
                      Where do you get 5 million pounds? I have 3.3 million pounds of force per SRB, giving a combined total of 6.6 million pounds of force, or 29.4 kN. That's pretty darn close to the 33.4 MN of the S-IC.

                      I was thinking 2.3 million pounds per SRB and doubling it. I stand corrected. However, the SRBs propellant is shaped to gradually reduce thrust over time (to compensate for reducing weight of the stack and limit overall acceleration). The F-1s gain efficiency with altitude and at just before center-engine cu
                    • Total impulse -- thrust times time. Newton-seconds, if you like metric

                      Gotcha. :-)

                      "Efficiency" don't enter into it, without defining all your terms. If the Shuttle really had "a far greater efficiency than the Saturn V" (defining "efficiency" as "lift capacity"), it'd be able to put an Apollo CSM/LM combo (or equivalent mass) into trans-Lunar orbit, or a Skylab-equivalent into LEO. It can't do either, although arguably the Orbiter itself, with a Spacelab or Spacehab in the cargo bay, is nearly Skylab-equival
                    • However, the SRBs propellant is shaped to gradually reduce thrust over time (to compensate for reducing weight of the stack and limit overall acceleration).

                      Yep. The SRBs could be made to maintain maximum thrust throughout the flight, but doing so would probably result in critical Q. Damned powerful buggers, but also damned uncontrollable. :-/

                      The center engine on the SatV cuts out for the same reason, but at a later time. The Space Shuttle hits Max Q at about 1 minute into flight whereas the Saturn V hits it
                    • The Shuttle stack limits acceleration to about 3G, the SatV at that point to about 4G. Center engine shutdown is well past Max Q at about 2 minutes 15 seconds, where the acceleration is approaching 4G. The outboard engines continue to burn for another 25 or so seconds beyond that. The SRBs only burn for 2 minutes.

                      But this is where we get back to my point about the Shuttle and the Saturn V being just different. The Space Shuttle roars off the pad with a thrust-to-weight of 1.74:1. The Saturn V, on the other
                    • Any way you cut it, though, the Shuttle is a massive technological advancement over the Saturn V.

                      One would hope so, 1970s technology being so much more advanced than 1950s technology. That's not always a good thing, though -- newer technology is notorious for teething problems that take a while to get the bugs worked out.

                      It's more efficient,

                      For some arbitrary definition of "efficient".

                      has more powerful engines,

                      Which are harder to control.

                      can carry more weight,

                      Not. Gross liftoff weight of the Saturn V wa
                    • Cargo weight to Earth orbit of Saturn V was about 259,000 lbs, of Shuttle about 60,000 lbs (excluding Orbiter weight -- we're talking cargo you can leave in orbit)

                      This is a pointless distinction to make when you're comparing engines and raw lift ability. The Shuttle lifts more mass to orbit despite a lower liftoff mass. Period, end of story. The details over what's cargo and what's ship are completely ancillary to this discussion.

                      Sure, Shuttle-derived cargo designs that use e.g. engine pods rather than an o

          • Re:Not really a surprise (Score:4, Informative)

            by AJWM ( 19027 ) on Wednesday February 01, 2006 @07:36PM (#14621899) Homepage
            The startup sequence for the F1 is hairy as all get out (taking about 7 seconds from "ignition sequence start" to full power). Furthermore, while it may be apocryphal, Harry Stine once told me that the ignition sequence was controlled by a patch-panel programmed computer and that the documentation for the patches was long since lost and those people that knew how to do it have mostly died off.

            The F1 ignition sequence includes steps like pre-filling the inlet tubes with a hypergolic mix to actually light the thing, diverting some of the fuel (kerosene) to the hydraulic system for the gimbal actuators, a controlled chill of the lox plumbing without getting the kerosene plumbing too cold (don't want any frozen lumps in there), starting the gas generators to power the turbopumps, etc. -- not necessarily in that order. The SRB ignition sequence is basically just detonating a small bomb at the top of the hollow solid fuel core.

            Personally I like the idea of resurrecting the F1, but the difference in experience and reliability levels between F1 and SRB vs J2 and SSME are considerable -- and in the latter case the J2 start is simpler than the SSME start.

          • F1 vs. SRB is a complex set of trade-offs. The SRB is extremely reliable (other than the o-ring problem). There's simply nothing to fail that results in thrust stopping (even in the Challenger failure, the SRBs kept thrusting). The F1 has many moving parts to fail and cause loss of thrust.

            OTOH, the F1 can be shut down on launch and throttled throughout the boost phase as needed. The SRB cannot be throttled at all. The current SRB design doesn't allow for thrust vectoring at all.

            Those are the reasons tha


        •     Yup. SRB's are metal tubes full of solid fuel, that burn at a steady rate. They burn until they're empty. No choice on that. Once they start going, that's it. When they're done, they're hollow tubes that come crashing back down into the ocean.

              There is nothing technical to them. Joe technician goes out there with his zippo, and lights the fuses, and off she goes. :)

              (just kidding on the Zippo thing)

      • You can't throttle the F1. It's either all-on or all-off. The Saturn V dealt with Max-Q issues by completely shutting down the center engine.
      • The only thing that makes me leery of the manned configuration (J2 ontop of an SRB in a vertical stack): Have they solved the temperature related problems on the SRB yet? Or have they implemented a workaround of only launching in warm weather?

        Of course, without an ET to catch fire and burn on the manned configuration, a Challenger type failure should be survivable due to an escape tower.
    • SSME (Space Shuttle Main Engines) - LHOx Fuel - 1.8 MN
      SRB (Solid Rocket Booster) - Solid Fuel - 14.7 MN
      J-2 (2nd and 3rd stage Saturn V) - LHOx - 890 kN
      F-1 (1st stage Saturn V) - Kerosine - 6.7 MN

      How do these compare to the disposable engines used on the latest Soyuz boosters?

      • They don't. Or more precisely, the Soyuz doesn't. It's not even in the same class. Here you go:

        RD-117 - First Stage (4 Engines) - 838 kN
        RD-118 - Second Stage (1 Engine) - 792 kN
        RD-0124 - Third Stage (1 Engine) - 294 kN

        You probably don't even want to see the Isp figures on those.

        The four RD-117s in the first stage produce a total of 3.3 MN, or less than 1/4 of a single SRB. The second stage engine is about 100 kN less powerful than the J-2, and the third stage is about 1/3 as powerful as a J-2. In comparison
        • They don't. Or more precisely, the Soyuz doesn't. It's not even in the same class.

          Yeah, given a few moments thought I should have figured that out for myself. Soyuz launches a tiny capsule, the SSMEs launches a whole friggin' aeroplane...

          According to the article you linked to Energia used RD-170 rocket engines, which produce 7.8 MN each. That's quite significant, and better than the F-1 according to the figures you gave. What's more, Wikipedia says that they're still in use by Sea Launch among others, w

          • Admittedly, I doubt they're man-rated

            You're sure about that? [wikipedia.org]

            Just so you're aware, the Energia was designed to carry the Russian Space Shuttle Buran. While no manned flights were ever accomplished (just a single, computer controlled flight), the rocket was ready for prime time.

            But yeah, the RD-170 is an incredible engine. That's why they reworked it to create the RD-180 for the Atlas V. :-)

  • 2018? (Score:3, Insightful)

    by Etnie ( 11105 ) <brieder&gmail,com> on Wednesday February 01, 2006 @04:21PM (#14619962)
    I'm a bit confused as to how it takes us longer to get to the moon now than it did in the 60s.

    Project Apollo was announced July 28th, 1960. July 20th, 1969, we set foot on the moon. Just under 9 years. (My dates may be a bit off.)

    Even if you say the new project starts now, that's still 12 years. How frustrating.

    • Re:2018? (Score:3, Insightful)

      by Kesch ( 943326 )
      There's probably a Murphy's Law of Government somewhere that the time it takes a government body to complete and action is directly proportional to the amount of regulations and oversight that exists. Regualtions and oversight are in turn directly proportional to the age and size of the government.

    • Re:2018? (Score:5, Informative)

      by AKAImBatman ( 238306 ) <akaimbatman@ g m a i l . com> on Wednesday February 01, 2006 @04:30PM (#14620080) Homepage Journal
      I'm a bit confused as to how it takes us longer to get to the moon now than it did in the 60s.

      1. Money. If we spent as much today as we did on the Apollo program, we'd be able to get a craft ready in a very short period of time. (Note that while NASA receives more than enough money, most of it goes toward the Space Shuttle's maintenece and other projects.)

      2. Technology. The industry that produced the Saturn V doesn't exist anymore, so it is not really possible to produce it again. We can produce a new rocket like the Saturn V (or buy off the Energia, take your pick), but that would just give us another moonshot rocket. What we want to build this time is an infrastructure that will keep us on the moon instead of merely sending up a few tons there and back.

      If there was an emergency, I imagine we could get to the moon inside two years. Most of the lander equipment can be remanufactured and lifted by the Space Shuttle, and strap-on boosters could be lifted to propell the module. But that's not the point. That's why we're doing this the right way this time. Or to put it in perspective, the Apollo missions started out with 2,900 tons of hardware. They came back with about 6 tons. That means that they expended 2,300 tons of hardware to get 3 people to the moon and back. That's a hell of a lot of waste! :-)

      • some numbers (Score:5, Informative)

        by Quadraginta ( 902985 ) on Wednesday February 01, 2006 @05:20PM (#14620672)
        Apollo cost about $135 billion [wikipedia.org] in 2005 dollars, and the CEV is expected to cost $15 billion [wikipedia.org].

        • Re:some numbers (Score:3, Interesting)

          by DerekLyons ( 302214 )

          Apollo cost about $135 billion in 2005 dollars, and the CEV is expected to cost $15 billion.

          Note that you are comparing apples (the cost of the entire Apollo program) to oranges (the cost of one spacecraft program).

          The whole VSE pork barrel includes the CEV, two new shuttle 'derived' launchers, the lunar modules, launch pad modifications, VAB modifications, new buildings and trainers, etc..., etc... *That* is what you should be comparing to the cost of the Apollo program.

          (For reference, the Apollo CSM pr

          • Eh, I know, and thanks for the addition. But maybe it's not apples to oranges so much as Fuji apples to red delicious apples.

            I debated whether to cite the cost of the Apollo booster alone, or the CM, to the CEV, because the CEV isn't just a new crew module, but on the other hand it's going to make considerable use of existing booster tech (e.g. the SRBs). Then I thought about the fact that I dunno if the cost cited by Wikipedia includes operating costs on the ground or not, some of which in the 1970s were

      • Re: waste? (Score:3, Insightful)

        by Migraineman ( 632203 )
        The expendable portion of a lunar mission isn't necessarily waste. You took a bunch of survey equipment (including a golf cart) to the moon. Why would you expend structure and fuel to bring it back? Similarly, you need structure and tanks to contain the fuel you're using to get to the moon. When the tanks are empty, why would you haul that empty (and now useless) mass around? Nope, the most efficient method requires you to be an interstellar litterbug. As soon as a resource is depleted, you jettison a
        • The expendable portion of a lunar mission isn't necessarily waste. You took a bunch of survey equipment (including a golf cart) to the moon.

          It wasn't really cargo, though, because we had to send up one with each mission. If the rovers were reusable, I would concede the point. Same with the lunar lander. (14 metric tonnes) The RTG generators used for lunar experiments have been in continual usage, however, and meet the critera of cargo.

          Unfortunately, even if you didn't count all of this as direct waste, the

      • The industry that produced the Saturn V doesn't exist anymore, so it is not really possible to produce it again. We can produce a new rocket like the Saturn V (or buy off the Energia, take your pick)

        The Energia is just as dead as the Saturn V.

        What we want to build this time is an infrastructure that will keep us on the moon instead of merely sending up a few tons there and back.

        Which is precisely what NASA isn't doing. The current scheme, just like Apollo, will end up providing expensive white elephant

        • Re:2018? (Score:3, Interesting)

          by AKAImBatman ( 238306 )
          The Energia is just as dead as the Saturn V.

          Funny, I coulda sworn I saw some Zenits and Atlas Vs flying.

          The Energia is far from "as dead as the Saturn V". Most of the technology is still in place, and much of it is still in use. As far as rockets go, it was one of the best pieces of engineering that Russia ever produced.

          Which is precisely what NASA isn't doing. The current scheme, just like Apollo, will end up providing expensive white elephants. Too expensive to keep us on the moon.

          You keep telling yoursel

          • Re:2018? (Score:3, Insightful)

            by bhima ( 46039 )
            Actually I've thought for a while that the US should be paying the Russians to host all of the American launches using chemical engines.
            Hell the EU should probably do the same thing. I wonder how much more science we could do if we subcontracted with Russians for launch vehicles?

            That would free many scientists & engineers to concentrate on newer more novel ways to get into orbit that don't include sitting on top of a bomb. Really there now there isn't an advantage to have US, French, British, Russian,

          • The Energia is just as dead as the Saturn V.

            Funny, I coulda sworn I saw some Zenits and Atlas Vs flying.

            So? Those are Zenit's and Atlas V's - not Energia's.

            The Energia is far from "as dead as the Saturn V". Most of the technology is still in place, and much of it is still in use.

            So what if the technology is still in place? The design team is long scattered. The parts are no longer in production. The assembly hall filled with dust and rust... The Energia is dead.

            As far as rockets go, it [the Ener


      • You don't have to launch with 2,900 tons of stuff. You have to launch with a crew and oxygen to get them to the ISS.

        There are Soyuz and Progress launches almost every month, carrying stuff up each time. They could make the launches more frequent, and assemble the ISS to Moon vehicle there. They could even bump an unmanned vehicle from the ISS to a moon orbit, and wait for the crew to get there to land it. They'd just need a nice comfortable vehicle big enough for the crew
      • If we spent as much today as we did on the Apollo program, we'd be able to get a craft ready in a very short period of time.

        There's nothing in the world to support that contention. It seems a lot more likely that if we spent as much today as we did on the Apollo program, we would get a lot less, thanks to the bureaucracy and regulatory mess.
    • Last time we were going for the sole purpose of beating the Russians there. This time we are (presumably) going there to stay.
      • Unfortunately not.
        This is not that much more than Apollo.
        A few people on the moon, for a bit longer than apollo.

        No manufacturing things from lunar resources, or long-term bases at all.
        More up to date sensors on the experiments of course, which is nice.
        No significant development of anything that will make spaceflight cheaper.
        It's been $10K/lb (approximately) since the end of apollo, and it still is.
      • im afraid we are going there to occupy the high ground and to threaten to drop boulders on those who threaten us.
    • Even if you say the new project starts now, that's still 12 years. How frustrating.

      I got news for you, it's not gonna happen ... not with an 8 trillion (and growing) debt, not with the pending baby boomer retirement and especially not with the US mired in a perpetual war. We'll be lucky to see the JWT launched before things go to shit.
    • As the mouths of politicians travel close to the speed of light, time slows down. Thought everyone knew that.
    • I'm a bit confused as to how it takes us longer to get to the moon now than it did in the 60s.

      Back then, they only had to include about 50 kilobytes of software in the rocket. This time, there's probably going to be hundreds of megabytes of code. That's going to take a long time to write.


    • Don't forget, almost everything with the Apollo missions was new technology. We've played quite a bit with space travel and long durations in space.

      It wouldn't take 9 years to park someone's happy ass on the moon. I'd be willing to bet we *COULD* do it in a year, if the government(s) wanted to do it.

      Now, the "could" part of that, is if we were doing it right. If a *good* leader were to control the whole thing, keeping all parties happy and active. We *could*
    • many more opportunities for taxpayer money to end up in the (mis)appropriate hands ??? or merely because it's more expensive now - in modern dollars, and therefore must be spread out over more years ? or was the original merely a hoax, and now they're trying it for real ?
    • The 1960s moon project was just an effort to get a man on the moon first at all costs, and beat the Russians. It was optimized purely to get that footprint and flag up there - not to do any real science or set up a real presence or Earth-Moon infrastructure.

      To do it properly WILL take more time.

  • Headlines in 2020 (Score:4, Funny)

    by j_cavera ( 758777 ) on Wednesday February 01, 2006 @04:58PM (#14620430)
    I can see this one coming:

    In the latest round of budget cuts, NASA introduced plans to modify the CEV for the planned Moon landing in 2038. The original plan called for an updated J-2 engine first used on the Saturn V rocket. The new plan is to have a guy sitting on the outside with a fire extinguisher. The fire extinguisher engine was first used in a high-school physics lab in the 1930s. It is not expected to save any money in the near-term, but in the far term, it should be a cost saver since the technology already exists and is proven.

    - Jim

    And yes, I AM a rocket scientist...
    • Just a bit cynical, are we? :-)

      I can understand your point (all too well I'm afraid), but you do have to admit that the CEV plan has really been shaping up. While just about every STS replacement technology before it tried to go for pie-in-the-sky technology, at least the CEV is mostly a matter of plumbing existing components together and certifying the sucker. It's not exactly a bold plan (any schoolchild could have come up with the idea of using the shuttle without the shuttle), but it at least is a good

  • In the 10 Apollo launches aboard the Saturn V rocket, there were no problems with the launch vehicle.

    I seem to rember in Apollo 13 the center 2nd stage engine, a J-2, went out early. The flight computer burned the outter four a bit longer to compensate, but I'd still say that was a problem, if not with the engine itself, at least with the launch vehicle. Then theres the whole lightning strike thing on what was it, Apollo 12? SCE to Aux.

    • Re:No problems? (Score:5, Informative)

      by rcw-work ( 30090 ) on Wednesday February 01, 2006 @05:46PM (#14620988)
      I seem to rember in Apollo 13 the center 2nd stage engine, a J-2, went out early.

      Dangerously strong pogo oscillations [yarchive.net], which could have ripped the engine off the rocket, happened to trip a pressure sensor which caused the computer to shut down the engine.

      Pogo was reduced to tolerable levels by the end of the Apollo series, and later engines such as the SSME were designed to eliminate it entirely.

    • Re:No problems? (Score:3, Interesting)

      by Ellis D. Tripp ( 755736 )
      The lightning-induced problems on Apollo 12 were isolated to the CSM, not the booster. In fact, the booster's guidance system is all that got the crew into orbit, because the CSM guidance system crashed along with most of the electrical system after the second lightning strike.

  • There's an opinion piece as to how NASA (Score:5, Interesting)

    by multiplexo ( 27356 ) on Wednesday February 01, 2006 @05:22PM (#14620689) Journal
    is turning the CEV into the same sort of flying clusterfuck as the Space Shuttle at:

    http://www.space.com/adastra/adastra_tumlinson_060 130.html [space.com]

    At this point I would rather save money by ending NASA's manned space program instead of continuing to piss money down ratholes such as the Shuttle, ISS and now the Crude Exploration Vehicle all of which are just ways for NASA to hand money to large aerospace companies so that they can pad their bottom lines and continue to bribe congressmen.

    • That article seems particularly concerned with forsaking methane for hypergolic fuels in CEV. There's a very good reason to use hypergolic fuels in a space vehicle--simplicity. A hypergolic engine doesn't need an ignitor or any form of electrical power to start--all you have to do is open the valves, which can be done by hand, and the engine will light when the reactants meet in the combustion chamber.

      If you have a damaged vehicle, the lack of a complex ignition system is another layer of redundancy to he
      • Yes, and the price for using hypergolic fuels is that the ground support infrastructure is very complex and the fuels are dangerous, toxic and expensive, which is why everyone who builds rockets has been moving away from them for the last 40 years or so. So the trade-off for a theoretical advantage in flight due to an added layer of redundancy is a huge and expensive layer of complexity on the ground to handle and store these fuels. Oh, and you lose some performance too, the specific impulse for hypergolics
    • Well, as always, there's that question: How much money should NASA spend on researching new technologies when the old technologies are "good enough"? The linked article, in some ways, and your opinion show the duality of this question.

      For example, you mention the "flying clusterfuck" of the Space Shuttle. I might agree, though I'd point out that many of the Shuttle systems are pinnacles of 1970s technology. Remember that, for the Shuttle, they created all new systems. Rather than using the old heat-shi
      • I'm a huge fan of the "if it ain't broke, don't fix it" school of design. On the other hand there are times when that doesn't work. The question with the CEV is whether or not NASA is going to turn this into another flying clusterfuck like the Shuttle, which NASA appears to have every intention of doing.

        NASA's decisions in the 1970s on the Shuttle made short term budgetary sense but were catastrophic in the long term. The SRBs were an unproven technology that was used not because it made good engineering

  • Misleading. (Score:5, Informative)

    by DerekLyons ( 302214 ) <fairwater@gmai l . c om> on Wednesday February 01, 2006 @08:51PM (#14622332) Homepage
    In the 10 Apollo launches aboard the Saturn V rocket, there were no problems with the launch vehicle.
    This is a bit misleading, the summary starts out talking about the engines, the swaps to the launch vehicle. In fact, the J-2 engines had considerable problems on the flight of Apollo 6 [wikipedia.org]. The pogo problem was not cured until Apollo 14. (In fact, though it was overshadowed by later events, it came quite close to causing an abort on Apollo 13.)

    In fact, when the Apollo series is looked at critically - one becomes astonished by the number of near misses and diving catches. NASA was lucky, very lucky.

    • This is a bit misleading, the summary starts out talking about the engines, the swaps to the launch vehicle. In fact, the J-2 engines had considerable problems on the flight of Apollo 6 [wikipedia.org]. The pogo problem was not cured until Apollo 14. (In fact, though it was overshadowed by later events, it came quite close to causing an abort on Apollo 13.)

      Isn't pogo more about the design of the rocket as a whole than just the engine, which is the part that is being considered here? I really don't know, I'm

  • One of the original stated benefits of the program was that by tinkering a little with shuttle derived components, they could create new launch vehicles without much new work. If they aren't using shuttle parts, why the hell don't they just design a new vehicle from scratch?
    • No, it doesn't defeat it at all. They will still be tinkering with pre-existing, proven hardware. Designing a new engine from scratch and flying it dozens of times to obtain the same confidence in it's reliability that we have about the Saturn, Apollo and Shuttle hardware would be vastly more expensive.
  • Personally, I think that someone at NASA finally woke up. Using an SSME in an expendable sustaner configuration is like shooting a thoroughbred racehorce after one race. You might win the race, but you paid way too much for it.

    People keep saying "well, we haven't made J-2's in 30 years". Well, nobody has made an airstart-capable SSME ever. Either way, changes will have to be made in production. Airstart isn't just a matter of throwing a switch and having the thing light up. Someone in a previous post
  • In the 1960s it took America slightly more than 8 years to go from a dead start (John Kennedy's initial announcement of the moon program) to landing on the moon using a J-2 engine. Now, 40 years later, it's going to take 12 years to land on the moon again, using a J-2 engine. My country peaked a long time ago.
  • When this came out a month ago, it was clear that NASA had embarked on the path you already know. Time to start cutting back. Due to the lack of thrust from the J-2 engine, they had to reduce the size of the spaceship. Due to lack of money, they had to abandon the methane engine and abandon a docking system. Due to the lack of a methane engine, they had to abandon synthesizing fuel on other planets.

    As said before, there is no moon program. If they ever get anything, it's going to be a low earth orbit c

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