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NASA Space Hardware

Will The Next Generation of Spacecraft Land In the Water? 318

Reservoir Hill writes "Work is progressing on the design of the new Orion Crew Exploration Vehicle (CEV), the next generation of NASA spacecraft that will take humans to the International Space Station, back to the Moon, and hopefully on to Mars. One major question about the spacecraft has yet to be answered. On returning to Earth, should the CEV land in water or on terra firma? After initial studies, the first assessment by NASA and the contractor for the CEV, Lockheed Martin, was that landing on land was preferred in terms of total life cycle costs for the vehicles. Getting the CEV light enough for the Ares rockets to be able to launch it, and therefore eliminating the 1500 lb airbags for landing has its appeal. A splashdown in water seems to be favored."
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Will The Next Generation of Spacecraft Land In the Water?

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  • by pkadd ( 1203286 ) on Friday December 14, 2007 @02:04PM (#21699750) Homepage
    Something i used to think of as a kid was: How about using the propulsion you get from the water for initial thrust of the spacecraft? Sort of like the effect you get from releasing a bottle of air under water, couldn't that be utilized in a cheap way of getting that initial upwards thrust, or would it be too cumbersome to make a vessel that is light enhough for it to actually float?
    • Re: (Score:2, Insightful)

      by 427_ci_505 ( 1009677 )
      I'd imagine that would be insanely hard to control even if it was possible.
    • Re: (Score:2, Informative)

      by gentimjs ( 930934 )
      You'd spend more energy getting the buoyant "rocket" down deep underwater and keeping it there, and then it probably wouldnt 'bound' more then a few feet out of the water. Check out a video of a submarine doing an "emergency surface" then consider if it would help get the submarine into space. Interesting idea, but No-go.
      • Re: (Score:3, Interesting)

        by sholden ( 12227 )
        Yes you wouldn't get enough velocity to make a it worthwhile, but spending more energy on the ground (well under the water...) doesn't matter. If you could come up with a way to use ten times as much fuel (for a given total weight) to launch a rocket than the standard approach, but have that fuel be used on the ground and not be lifted by the rocket it would be used in a flash (it's what a rail gun launch would be after all) - assuming you manage to not turn the people inside to smears on the wall...
        • by IdeaMan ( 216340 ) on Friday December 14, 2007 @03:06PM (#21700646) Homepage Journal
          Actually the submersion idea is brilliant. The piece missing is the launch tube.
          Build a 30 foot diameter tube 2 miles deep, with a piston on the bottom. Put brakes on the piston that will limit the acceleration down to about 5G. Empty the piston of water, lower spacecraft onto piston, when you launch just let the piston rise. The thousands of PSI of water pressure should give the spacecraft a significant amount of speed by the time it reaches the surface, light off rocket at a higher altitude than normal so the nozzle can be optimized for a higher altitude burn. I'll work on the math for this.
          • I'm just a mechanical engineer and not a rocket scientist, but it is my intuition that the rocket would start to decelerate as you came close to the surface - the pressure differential would get smaller and smaller and smaller as you approached the surface.

            Anyway, watching a submarine do an emergency surface [] should show you how something much lighter than a rocket doesn't even leave the water completely.
          • by IdeaMan ( 216340 ) on Friday December 14, 2007 @04:34PM (#21701924) Homepage Journal
            The setup:
            30 mile long tube buried at a shallow angle, say 5-20 degrees. This lowers the pressure requirements at the bottom end of the tube.
            Pressure (every 33 feet per 14.7 psi) Depth = sin(20)*length in feet = 24,100 psi
            Acceleration = 5G, d = 1/2*a*t^2, therefore T = 44.5 seconds.
            V = Acceleration * time, therefore V = 7110 ft/s
            1 m/s = 3.28 ft/s
            Delta-v to low orbit is 8600 M/s, or 28000 ft/s

            So this method will give us 1/4 of the delta-v needed to get to low orbit.

            If an ocean contour could be found that somewhat matched the angle involved, the tube buoyancy and alignment problem could be solved by anchoring it to the sea floor.

            12G at 50 miles, 20G@30 miles give 14kft/s (1/2 low orbit delta-v)
            50G @ 50 miles gives 29kFt/s, more than enough for LEO if you ignore drag.
            This class of launch tubes would be suitable for refueling geo-synch shuttles.

            62 mile tube @ 10 degrees (similar idea as the 100km launcher proposed for Antarctica) gives 25kPSI, 9k deltav @ 4 g.

            I'm not sure if it would be easier to build a straight tube in Antarctica or in the Ocean.
            One other problem is that once you surpass the speed of sound in a medium you no longer receive thrust from it. Speed of sound in water is 1482 m/s, or 4862 feet/s, so you would need to start pumping a hot gas, either rocket exhaust or hot hydrogen into the tube once you passed 4.8kft/sec.
    • Re: (Score:3, Interesting)

      by jackpot777 ( 1159971 )
      Isaac Asimov used that idea in The Martian Way (short story, Martian colonists solve their water shortage problem by going to Saturn and bringing icy ring chunks back). He had a 'micropile' heat some of the ice to steam, then have it shoot out at extreme pressure. As acceleration = force / mass, and the force was great, the acceleration was equally as great, and the constant acceleration got the colonists back to Mars in a matter of weeks.

      To use that to escape Earth gravity, though ...think of the power of
  • Simple Answer (Score:2, Insightful)

    by gentimjs ( 930934 )
    Re: "Getting the CEV light enough for the Ares rockets to be able to launch it," .. the solution is simple .. buy/license/whatever the Energiya booster from the ruskies instead, and you'll have much more weight to play with.... OH sorry, I forgot, the Energiya isnt build in the correct congressional district... my bad.
    • No, what you forgot is that there isn't any such thing as an Energiya booster. The Energiya was scrapped years and years ago - and never was fully operational in the first place.
    • Re:Simple Answer (Score:5, Informative)

      by ianare ( 1132971 ) on Friday December 14, 2007 @02:32PM (#21700152)
      The planned Ares V has a mass to LEO [] of 130,000 kg, the energia has 'only' 88,000 kg, so the solution isn't that simple. Besides, any weight savings on any system is obviously an advantage when the cost per kg is so high.
      • by ianare ( 1132971 )
        on further reading, one of the engines used in the Atlas rockets is in fact the RD-180 [], developed and built by the Russians.
    • Re:Simple Answer (Score:4, Insightful)

      by p0tat03 ( 985078 ) on Friday December 14, 2007 @02:52PM (#21700442)

      There are some very good reasons for building an all-American rocket beyond mere politics. It has everything to do with developing domestic expertise in the field, and encouraging R&D in the country for these technologies, which can only serve as a foundation for developing even more.

      Beyond what the other posters have mentioned, brute forcing the problem is also rarely a good solution. Instead of spending tens of million each launch to lift a huge, heavy spacecraft into orbit, its weight should be optimized, both for the sake of proper engineering and for the sake of cost cutting. I won't presume to know the specific technical difficulties of a project as complicated as the CEV, but there's a balance between more lift power and reducing spacecraft weight.

    • Oh, good lord. What Energiya would that be? The prototypes corroding away somewhere, never having been launched? There is no such thing as an Energiya, aside from old photos with a Buran attached, and some blueprints. You'd do better to start from scratch than with Energiya plans.

      And of course, you overlook the many domestic alternatives that *actually exist*. Like EELVs (Delta and Atlas). Or those that could be restarted since they just quite making them a few years ago (Titan IV - ro
    • by Criton ( 605617 )
      A brain dead simple answer would be to use direct launcher [] as the crew launch vehicle. Direct launcher makes use of existing four segment srbs and existing RS68s plus it lifts 50tons in it's most basic form vs 25 for Ares I mass problem solved and 2 billion saved on Constellation. The only answer I can think of right now is the fire Griffin it's the only way to save the project. That or kill Orion outright and give all the budget to COTS type programs. I see no hardware for Or
    • Re: (Score:3, Insightful)

      by GreggBz ( 777373 )
      How is this modded insightful? Just because it poo-poos America? The Energiya is not in production. We don't know if the larger (theoretical) models are worth anything. They may be based on prior proven technology but so is the Ares. There are certain to be major engineering differences (fuel, electronics, avionitcs) that we don't have the support infrastructure for. And lastly, even though NASA has a pretty good history of cooperating with foreign agencies in space, what is wrong with building something ou
    • by Ecuador ( 740021 )
      And also, you could have bought the Buran project (for next to nothing - after the collapse of the USSR it could not be sustained anyway), and now have a Space Shuttle equivalent that can carry more and NEEDS NO CREW (at least for easy missions). How much safer than that can you go?
  • Water or land? (Score:5, Informative)

    by GenKreton ( 884088 ) on Friday December 14, 2007 @02:08PM (#21699804) Journal
    As someone who worked partially on the CEV, it has been decided. it is in the requirements that Lockheed Martin furnish a vehicle that is capable of both. One of the design limitations now is that it must actually be stable in swells of up to 14 feet, which are not uncommon in the cold North Atlantic - emergency abort scenarios land all launches there during early lift-off stages. There are huge problems with ill-effects of ocean landings for crews and they really are looking to avoid it, but even with parachute and pillow systems, they are looking at potential damage,
    • Since the craft is coming down fairly fast, isn't the impact of landing on water or land about the same?
    • An excellent question of terminology. The current generation of spacecraft waters safely on land. Will the next one be able to water on water?

    • As someone who worked partially on the CEV, it has been decided. it is in the requirements that Lockheed Martin furnish a vehicle that is capable of both.

      The capability to be able to do both has been decided; the decision as to which they will preferably use on an ongoing basis has not been decided, and that is what TFA is about.

    • Can't we simply vote for it to land on Cowboy Neal?

      Sorry, had to get that in there. I couldn't help but feel the summary was asking us for our uninformed opinion.

      It sounds to me like you're talking about the requirement that has been with the system from the beginning that it be able to ditch in the ocean, regardless of the nominal landing profile. What NASA is trying to decide now is if it should normally land in the ocean and face the added recovery hassle and risk, or on land and need to accomodate
  • by ( 1108067 ) on Friday December 14, 2007 @02:08PM (#21699806) Homepage Journal

    "One if by land, two if by sea ..."

    Seriously, why not just do the moon mission, then pick up the landing bags as the ISS on the way home. Better yet, why not have a specialized vehicle just for orbit-to-moon-and-back, and transfer to a special-use re-entry vehicle at the ISS?

    • by 2short ( 466733 ) on Friday December 14, 2007 @02:15PM (#21699902)
      Why involve the ISS (besides politics)?

      Just put whatever you want to rendezvous with in whatever orbit is convenient, it won't go anywhere.
    • Re: (Score:3, Insightful)

      by DerekLyons ( 302214 )

      Seriously, why not just do the moon mission, then pick up the landing bags as the ISS on the way home.

      Because that would actually _increase_ the mass boosted towards the moon by a factor of a thousand of more. (It takes a lot of fuel to brake into Earth orbit, and yet more to change orbital planes to match up with the ISS.)

      The next poster posited simply leaving the required module in a convenient orbit not at the ISS. This is a little better as it only requires increasing the mass boosted towards

      • by 2short ( 466733 )
        Based on my understanding, you're going to "break into earth orbit" upon return anyway; it's a matter of whether you keep breaking and re-enter, or orbit a bit first.

        Now, matching orbits to rendezvous with a previously deployed package may be a different matter; It will be no problem if everything goes perfectly. but if that rendezvous is required in order to re-enter, you're going to want a healthy safety margin on your ability to do it, and that margin will consist of fuel. Probably enough to weigh more
        • by Mercano ( 826132 ) <mercano@gm[ ].com ['ail' in gap]> on Friday December 14, 2007 @03:55PM (#21701340)

          Based on my understanding, you're going to "break into earth orbit" upon return anyway; it's a matter of whether you keep breaking and re-enter, or orbit a bit first..

          No, not really. The Apollos didn't preform any breaking maneuvers on the way back to Earth, they just hit the atmosphere at full speed and scrubbed off their speed there. If you enter shallow enough, you can burn off more speed in the upper atmosphere before you start getting into the thicker air, and a sufficiently durable heat shield turned out to be lighter then the fuel that would have been required to slow the ship down. In fact, even orbiting spacecraft generally burn as little fuel as possible to get themselves just bellow orbital velocity and then do the rest as atmospheric breaking.

    • As someone already pointed out involving the ISS would be a waste.

      More to the point though... there are already 3 parts being assembled in space IIRC. The Orion capsule goes up alone, where it attaches to the "earth departure stage," the rocket it needs to leave earth orbit, and the new lunar lander (Altair, named yesterday). But taking airbags up separately.... wouldn't be easy. It would mean a (or an additional?) zero-g EVA to insure each bag attached properly. Not to mention it costs quite a bit of m
    • by delta407 ( 518868 ) <slashdot.lerfjhax@com> on Friday December 14, 2007 @02:46PM (#21700372) Homepage
      Why not pick up the landing gear on the way back? Let's investigate.

      Recall: Apollo's flight plan was an initial burn to get into earth orbit, another burn to leave orbit on course for the moon (trans-lunar injection), another burn to get in orbit of the moon, and another burn to leave orbit on course for earth (trans-earth injection). That's it. They didn't return to orbit after leaving the moon. They left the moon, coasted for a couple days, hit their entry interface, then hit the Pacific.

      Why? Going back into orbit requires adding two more burns: one to enter Earth orbit, and another to leave it. Adding a rendezvous with the ISS (or any other floating payload) means an additional 1-2 burns to match the orbital planes, an additional burn to raise or lower your orbit, and God knows how long until the orbits of the two vehicles sync. Look at the space shuttle: even with matching the orbital planes and scheduling launch for an ideal rendezvous profile, it takes them 36-48 hours to catch up with the space station.

      Trans-earth injection is complicated enough without adding all that. Extra burns means extra propellant, which means extra weight, which is exactly what you're trying to avoid. Not to mention, each of those steps is another opportunity for failure, and how do you abort if you don't have landing gear?

      This is why they are Rocket Scientists(TM).
    • Re: (Score:2, Informative)

      by Robonaut ( 1134343 )
      When returning from the moon, a spacecraft has significant excess velocity. Entering back into an Earth orbit (like rendezvousing with the ISS) means that the CEV would need to make a burn to slow down. This would consume a significant amount of fuel (that very well could weigh as much or more than the airbags). Instead, the Apollo CM and the CEV are designed to plunge directly into the Earth's upper atmosphere, literally burning off the excess velocity through atmospheric drag. This requires a larger h
    • Because that plan would involve FAR more weight than any proposed air-bag system. To "stop" at the ISS would require that a large amount of braking fuel be carried all the way to the Moon and back just to reduce the velocity to Earth Orbital velocity. As opposed to letting friction slow you down.

      There is some potential value in an Earth orbit "stop" on the way out (as was one of the baseline plans for Apollo, early on) but definitely not on the way back, if you can build a thermal prot
    • Why, the royalties alone from the 2001 soundtrack they'd be playing on every leg would put them over budget.

    • Seriously, why not just do the moon mission, then pick up the landing bags as the ISS on the way home.

      The moon and the ISS are orbiting in planes 45 apart. It would require a prohibitive amount of fuel to get from the moon to the ISS. They'd pretty much need another fuel tank and another pair of solid rocket boosters to get there.

      Traveling in space is not like traveling on the ground. On the ground, if you want to go somewhere, you only have to move to its position. In space, getting to a given position is the easy part; it's getting to the right velocity at that position that is hard.

      For instance, if

      • Actually... (Score:3, Informative)

        by p3d0 ( 42270 )
        Having taken the time to write all that, I'm not sure it's true now. I think it takes about the same fuel to get from the Moon to pretty much any low Earth orbit you want, including the one with the ISS in it.

        Too bad. I thought that was a pretty good explanation, except that it's wrong. :-)
        • Re: (Score:3, Informative)

          by AJWM ( 19027 )
          Actually your explanation is mostly right -- you just omitted the fact that the gravitational force of a large body (the Earth, Moon, or Jupiter for outer solar system missions) can be used to change velocity (either direction or speed) too, as can aerobraking.

          Approaching the Earth from the Moon at a slight angle, ie aiming toward one pole or another rather than the equator, lets you use Earth's gravity to help change the orbital plane. You still need to shed a lot of velocity to establish Earth orbit, but
  • So... I don't really understand the whole disposable crew idea. It would make sense to reuse the crew rather than feeding them to sharks after re-entry, or did I miss something.
  • Bad Summary? (Score:2, Insightful)

    by 2short ( 466733 )

    "landing on land was preferred in terms of total life cycle costs for the vehicles."

    Landing on land is cheaper, check.

    "eliminating the 1500 lb airbags for landing has its appeal"

    Landing on land lets it be lighter, check.

    "A splashdown in water seems to be favored."

    Huh? WTF? Am I supposed to go RTFA or something?

    • by mashade ( 912744 )
      I was puzzled in the same way. Perhaps it gets to be lighter if outfitted for nautical landing, and that simply wasn't made clear. [/didn't rtfa]
    • by LWATCDR ( 28044 )
      "eliminating the 1500 lb airbags for landing has its appeal"

      "Landing on land lets it be lighter, check."

      The airbags are used for landing on LAND.
      They are not flotation devices. Any thing that can fly is going to light enough float on water if it doesn't leak.
      The airbags are to reduce the impact.
      • by p0tat03 ( 985078 )
        Except spacecraft rarely *fly*. They float in space, or they are free-falling back to Earth. Neither of which suggests any innate ability to stay afloat.
      • "eliminating the 1500 lb airbags for landing has its appeal"

        "Landing on land lets it be lighter, check."

        The airbags are used for landing on LAND.
        They are not flotation devices. Any thing that can fly is going to light enough float on water if it doesn't leak.
        The airbags are to reduce the impact.

        this had me interested because i could have sworn that they did have flotation devices on the previous rocket capsules, but according to this page [] the only flotation devices were [presumably small] airbags that were used to right the capsule and a flotation collar that was attached by the pickup crew that ensured that the capsule stayed upright after the hatch was opened.

    • by PhxBlue ( 562201 )

      Huh? WTF? Am I supposed to go RTFA or something?

      No, just read the summary a bit more closely. Landing on water lets the engineers ditch the airbags. Landing on solid ground without the airbag system would be a bit ... jarring, to say the least.

    • "landing on land was preferred in terms of total life cycle costs for the vehicles."

      Landing on land is cheaper, check.

      "eliminating the 1500 lb airbags for landing has its appeal"

      Landing on land lets it be lighter, check.

      "A splashdown in water seems to be favored."

      Huh? WTF? Am I supposed to go RTFA or something?

      The 1500lbs. of airbags are for cushioning the surface landing, not for buoyancy in water. As I understand it, the CEV will be required to have floaters regardless of the re-entry landing method because the abort scenario puts it in the ocean off the cape anyway, so the extra baggage for cushioning a land impact just facilitates a superfluous landing method.

  • It's much easier to hit the water, and in theory you should be able to get a softer landing on water. However, if you land in the middle of the south pacific, it's a bit more difficult logistically to pick you up from there and get you home, vs. landing on some runway with roads connecting it to the regular highway system of your homeland.
    • Re: (Score:3, Informative)

      by GenKreton ( 884088 )
      They want to land on land for recovery reasons and to save the crew the effects of being stuck out in the ocean in a waving buoy. With that said, you hit the nail on the head, finding land and aiming at it is significantly harder. That's why both systems are in the engineering specifications NASA gave us, and will be built into the final design, tentatively. The system for placing the capsule at a good location is not one of the design challenges facing Lockheed Martin's contract.
    • When they're out in the middle of the Pacific doing exercises. Why not have them pick up some astronauts on their way?
  • by Thagg ( 9904 ) <> on Friday December 14, 2007 @02:14PM (#21699878) Journal
    Lockheed, the Orion prime contractor, has expressed significant reservations about carrying the heavy airbags to the moon and back -- those 1500 lbs can better be used in other ways. On the other hand, there shouldn't be a problem with the weight on the more common missions to the space station and low-earth orbit, and the ability to reuse the capsule will be far greater if they put it down on land.

    The speculation in this week's Aviation Week was that they would have bolt-on airbags for the earth-orbit flights, and would recover those missions on the land, and would recover at sea for the moon-return missions.

    The reentry profile for the moon missions is really quite amazing. Recently Aviation Week had an article about it, describing how to get all the capsules to recover to the same spot on Earth. Do you recall way back in the Apollo days, they always described the narrow re-entry corridor? Too steep and you'd burn up, to shallow and you'd skip back into space forever? Well...

    For Orion, they plan to use a skip back into space to bleed off some of the speed coming back from the moon, and to align the craft to re-enter at the correct place to land where they want, off the coast of California. It's an incredibly audacious plan, with tolerances that have to be measured in tenths of a degree of entry angle. Very cool.

    • Exactly precise angles is one of the benefits of modern flight computers, which they didn't have for Apollo. I'd certainly expect them to put the crew in a pretty small circle in the ocean if they wanted to, today. Hell, I wouldn't be *that* surprised if they could land them in a big lake... or better yet a harbor or bay. the space shuttle manages to hit a runway, after all. Sure, it has wings and whatnot, but this is 20 years later, and a lake, bay, or harbor could be quite a bit larger.
      • by Nimey ( 114278 )
        One assumes they'll have alternate-landing profiles for when enough CM computers go down that the skip isn't feasible. The Shuttle has almost had to abort a flight because IIRC all but one of the flight computers went down on that mission.
    • by oni ( 41625 )
      For Orion, they plan to use a skip back into space to bleed off some of the speed coming back from the moon,

      I've always wondered why they didn't do that with the shuttle. The shuttle does S-turns and stays in the atmosphere the whole time. Why not pitch up to go back into space and cool down a bit? I'm sure the engineers thought of it and I'm sure there's a good reason, I just don't know what it is. Maybe the S-curves give them more downrange control.

      Speaking of apollo though, I read somewhere that apol
  • by BlueParrot ( 965239 ) on Friday December 14, 2007 @02:17PM (#21699952)
    To be honest in principle I don't see the downside of a water landing. The craft has to have a sufficiently low density to float, which could increase air resistance, but a certain degree of air resistance will be needed for re-entry anyway, too little of it and the majority of the slowdown will occur in lower ( i.e denser ) parts of the atmosphere. You want to decelerate over as long a distance as possible tor educe the requirements on the heat-shield. I guess you must test the whole thing for water-compatibility, but if it is to deal with vacuum, intense heat, and solar wind, I would imagine it should be able to deal with some water. I suppose there may be investment costs associated with developing new technology for water based landings, but it does seem like it should be the easier and more fault-proof way to do it, so I wouldn't be surprised if it will work out cheaper in the end.
    • by T.E.D. ( 34228 )

      To be honest in principle I don't see the downside of a water landing.

      For one thing, we all know a seat cushion will make a terrible flotation device.
    • Re: (Score:3, Informative)

      by CompMD ( 522020 )
      Its not the water that is a problem, its the salt in that water. You run into accelerated corrosion problems with exposure to ocean water.
    • by Nimey ( 114278 )
      It's not cheap to send a carrier battlegroup to pick up the CM after splashdown, and depending on the political situation it may be inconvenient and/or dangerous.
      • Why does it have be a carrier battlegroup? If you think about it anything big enough to carry the fucking thing will do. How about a destroyer or cruser. Hell, a fucking fishing boat would do if it was big enough.

  • by timeOday ( 582209 ) on Friday December 14, 2007 @02:22PM (#21700016)
    Gus Grissom []:

    "Following the splashdown of "Liberty Bell 7, the hatch, which had explosive bolts, blew off prematurely, letting water into the capsule and into Grissom's suit. Grissom nearly drowned but was rescued by helicopter, while the spacecraft sank in deep water. Grissom maintained he did nothing to set off the explosives to blow the hatch, and NASA officials agreed. The craft was recovered in 1999 but there was no evidence of how the hatch had been opened. However, later experience showed that the force necessary to trigger the initiator for the explosive egress system would leave a major bruise, and Grissom had no such injury."
    Actually I'm not sure this episode has any direct relevance to the present. Just thought it worth mentioning that the first manned space missions did land in water.
    • Re: (Score:3, Insightful)

      No, the first manned missions landed on land. The Soviet Union (now Russia) landed and continues to land all of their manned missions on land. If they can do it surely we can too.
      • No, the first manned missions landed on land.

        True, but there is one subtlety here: The Vostok 1 which carried Gagarin into space on April 12, 1961, had one very serious design flaw: a parachute-assisted landing of the reentry vehicle would be too violent for a cosmonaut to survive. Instead, Gagarin had to eject from the capsule at an altitude of 7 km and parachute to the ground. To make matters worse, his ejection system didn't kick in right away, and he spent some time in a wild spin before he was able

    • It was quite an issue at the time. They accused him of blowing the hatch. Maybe they don't want to go down that road ever again.
    • An additional irony of the Liberty Bell 7 incident was that the original hatch design for the Apollo spacecraft was an inward-opening door. This hatch design made it impossible for Grissom, White and Chafee to escape the Apollo 1 fire.

      The hatch was redesigned before the Apollo 7 flight (the first manned Apollo flight).

  • What I don't get (Score:4, Interesting)

    by BorgDrone ( 64343 ) on Friday December 14, 2007 @02:24PM (#21700046) Homepage
    What I don't get is the continued use of rockets. Is going straight up (the brute force & ignorance method) really the most efficient method of getting up there ? Isn't an approach like SpaceShipOne uses more efficient in terms of amount of energy needed per kilo of launched mass and thus costs ?
    • SpaceshipOne * 30 (Score:5, Informative)

      by Harmonious Botch ( 921977 ) * on Friday December 14, 2007 @02:48PM (#21700398) Homepage Journal
      Spaceship one was good for getting to the 'edge of space' and back. Being in orbit is a different thing. As a general rule, it takes 30 times as much energy to get into orbit as it does to just get up there. ( the number varies with altitude, of course, but 30 is a good back-of-the-envelope approximation ). The energy that has to be bled off when coming down is roughly 30-fold. So spaceshipOne is not even close to being able to do it. It requires new materials and/or a new design. Or stick with the high maintainence and unpleasant failure rate of the shuttle.

      Or you can stick to the simple way of doing it with rockets and parachutes.
    • Re: (Score:3, Insightful)

      by Nyeerrmm ( 940927 )
      If you're talking about air launch, it only gives you a minor improvement, and if you're talking about a heavy launch vehicle like Ares V, you're not going to find an aircraft capable of launching it. The Orbital Sciences Pegasus rocket launches off of an L-1011 aircraft, and has a fairly small payload.

      Remember that most of your energy is spent with energy in the direction of the orbit rather than going straight up, and thus why orbital flight is an order of magnitude more difficult that the suborbital fli
    • Re: (Score:2, Insightful)

      by Robonaut ( 1134343 )
      In theory, yes you are right. A couple things to remember however:

      1)SpaceShipOne was sub orbital (did not reach orbital velocities) and launching into orbit would require a couple orders of magnitude more energy/fuel.

      2) Everything else being equal, a spaceplane will cost more to develop than a rocket (aluminum tubes vs a plane airframe capable of hypersonic flight). Development costs are rather significant for spacecraft as the number of units produced is very low.

      3) It has been tried before, rather
  • Itll make a big splash.......sorry...very very tired.
  • no! (Score:3, Insightful)

    by Scrameustache ( 459504 ) on Friday December 14, 2007 @02:39PM (#21700254) Homepage Journal
    I'm 111% confident that it cannot land in water.

    Because it's water, not land, DUH!
  • by Chairboy ( 88841 ) on Friday December 14, 2007 @02:40PM (#21700274) Homepage
    For the folks saying "use the ISS!': Won't work. When coming back from the moon, the approach speed is far too high to enter the orbit that the ISS or any other reasonable future space station is in. The braking is done through friction as the spacecraft enters the earth's atmosphere, and provides MUCH more delta-v than would be feasible by using rockets.

    To use the ISS, the spacecraft would need to perform a complex aerobraking maneuver (basically, a partial re-entry), then have the fuel needed to circularize its new orbit so that it can rendesvous with the ISS. By the time this is done, the design for the capsule is far heavier than the 1,500lb penalty that airbags impose.

    My idea, make the water landing a known 'capsule loss' scenario, the same way it is with the Shuttle. If things go _so wrong_ that a water landing is unavoidable (say, launch failure) then design the capsule for quick-egress after a water landing. Airplanes ditch in water and people have time to get out before they sink. My Piper Cherokee will float long enough for me to climb out onto the wing, and for a real shock look at the survival training that helicopter passengers go through in the military, that's some pretty intense worst case scenario stuff.

    With Rogallo steerable parachutes, landfall should be available at all times except the first few minutes of launch. Skip the airbags, make the capsule so it stays afloat just long enough for egress, and train the astronauts on how to get out fast.
    • Airplanes ditch in water and people have time to get out before they sink. My Piper Cherokee will float long enough for me to climb out onto the wing

      Just hope you don't flip it over when you ditch. Then you can climb out. Cherokees being ditched have a bad habit of flipping over just as soon as the nosewheel hits the water due to the pilot trying to land it on the water as if on land, with the flaps down which gives that obnoxious nose-down pitching tendancy with the hersheybar wing. There seem to be two sc
  • don't see why this approach (other than $) is not taken.
  • by Anonymous Coward
    While Netcraft may or may not confirm it, the real truth is that this program is in a death spiral and is well on its way to cancellation, just like every major NASA program to replace the shuttle over the past two decades (SEI, NASP, X-30, X-33, X-38, OSP). For the gory insider details, read the recent GAO report, or the forums at nasaspaceflight, or the postings at spacepolitics or the rocketsandsuch blog. To sum it up, Ares I doesn't have enough performance to lift the Orion, so systems are being discar
    • dunno about that (Score:3, Interesting)

      by Quadraginta ( 902985 )
      First, of all, imagining that one guy at the top is bringing the whole enterprise to its knees is just classic populist wishful thinking. It never works that way. Herbert Hoover didn't cause the Depression, Joe Stalin didn't by himself cause the Cold War, Alan Greenspan didn't cause the dot-com bust or the mortgage meltdown, and your Mikey G isn't by himself blocking all future progress in manned spaceflight.

      Figuring out exactly how and why a program craps out is a matter for endless debate among histori
  • "Altair."

    That's the class name . . . I guess the individual ships will get knicknames, the way that the Apollo command modules and LEMs did.
  • I seem to remember needing little things like a squadron of choppers, and a fleet of ships in the intended splashdown area. These days, we don't have spare aircraft carriers with their support ships hanging around - we've mothballed a lot of them

  • I wonder why they just don't focus all their research resources on Robots and AI vs playing around, why not send automated units instead of 'live' people? automated units could be just as good if not better then people and save space/energy in the process. Not only that the spin off technologies from robotics and AI will have enormous implications for society here on earth and most likely for the better.
  • Do you mean intentionally, or are you using "land on water" in the same sense that airline instructions refer to "water landings"?
  • Does the entire capsule have to land softly? If not, you could have only the astronaut seats land softly, inside a capsule that slams down hard.

    The seats could hang in elastic fixtures that make them move just as far as external landing airbags would, just as softly or probably softer. The seats would be braked all the way through this movement, giving a more regular braking than external airbags.

    The volume of air where the seats move when landing would be used for that only while landing. During flight it
  • Wouldn't modern technology allow guiding the capsule with high precision to a specific target? If so, cover a field with suitable large, soft airbags, and have a capsule carrying no airbags land in the center of this field.

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