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Space Transportation

Russian Manned Space Vehicle May Land With Rockets 197

The Narrative Fallacy writes "Russia's next-generation manned space vehicle may be equipped with thrusters to perform a precision landing on its return to Earth. Previous manned missions have landed on Earth using a parachute or, in the case of space shuttles, a pair of wings. Combined with retractable landing legs and a re-usable thermal protection system, the new system promises to enable not only a safe return to Earth, but also the possibility of performing multiple space missions with the same crew capsule. The spacecraft will fire its engines at an altitude of just 600-800m, as the capsule is streaking toward Earth after re-entering the atmosphere at the end of its mission. After a vertical descent, the precision landing would be initiated at the altitude of 30m above the surface. Last July, Korolev-based RKK Energia released the first drawings of a multi-purpose transport ship, known as the Advanced Crew Transportation System (ACTS), which, at the time, Russia had hoped to develop in co-operation with Europe. 'It was explained to us how it was supposed to work and, I think, from the technical point of view, there is no doubt that this concept would work,' says Christian Bank, the leading designer of manned space systems at EADS-Astrium in Bremen, Germany. However, the design of the spacecraft's crew capsule had raised eyebrows in some quarters, as it lacked a parachute — instead sporting a cluster of 12 soft-landing rockets, burning solid propellant. Inside Russia, the idea apparently has many detractors. During the formal defense of the project, one high-ranking official skeptical of the rocket-cushioned approach to landing reportedly used an unprintable expletive to describe what was going to happen to crew members unlucky enough to encounter a rocket engine failure a few seconds before touchdown."
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Russian Manned Space Vehicle May Land With Rockets

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  • by religious freak ( 1005821 ) on Wednesday April 29, 2009 @11:25AM (#27760629)
    Of all the crap I've seen on /. I didn't realize we had unprintable expletives around here? Now, I'm curious - what could be so bad that it can't be printed on a /. page?!
  • by account_deleted ( 4530225 ) on Wednesday April 29, 2009 @11:26AM (#27760641)
    Comment removed based on user account deletion
  • by TheRaven64 ( 641858 ) on Wednesday April 29, 2009 @11:28AM (#27760671) Journal
    That's so retro.
  • Weight problems? (Score:4, Interesting)

    by eebra82 ( 907996 ) on Wednesday April 29, 2009 @11:31AM (#27760721) Homepage
    In other words, they must think that adding that extra fuel weight (for landing) is worth the extra fuel weight that is needed to launch the rockets into space. After all, the landing fuel will cost them a lot of extra weight. I don't know how much extra it would be, but it doesn't sound like a good idea.
    • Re: (Score:3, Insightful)

      by Red Flayer ( 890720 )
      Yes, but how heavy were the parachute, parachute deployment system, and parachute shielding system that they were able to remove?
    • Re:Weight problems? (Score:5, Informative)

      by snaz555 ( 903274 ) on Wednesday April 29, 2009 @12:00PM (#27761119)

      Without use of Kazakhstan, Russia has only a narrow strip of land that stretches far enough south to be worth launching from - and landing at. And this is not a flat desert wasteland. The reason for the rockets is to allow for a controlled landing. Parachutes are more suited for an ocean or desert landing where a few miles of accuracy doesn't make much difference. Presumably they figured that the weight of the landing system is outweighed by the benefit of launching (and landing) at a more southern latitude. Ocean landings aren't exactly free, either.

    • they must think that adding that extra fuel weight (for landing) is worth the extra fuel weight

      Or, they could get their fuel on space.

      Is there any cheap way of sending light materials to a space station and turn them into fuel there to make a refueling orbital station for returning spaceships?

      • Well, nothing in space is cheap. But we are currently using the cheapest methods of moving materials, or in the process of moving to cheaper methods. I think the Shuttle isn't very cheap when used to move raw materials, but there are somethings that only it is able to put in space due to size/weight of a discrete object.

        I think you are trying to invent the space elevator/gun or what not. Which sounds like a good idea. Go for it. Let me know when its operational, and I'll send a bottle of Sparking wine.

    • How much lighter would the Space Shuttle's orbiter be if it didn't have those massive wings, tail, aerodynamic chassis, and airliner-style landing gear? Would a simple landing rocket system weigh LESS than everything required to make the orbiter a glider?
    • by tsotha ( 720379 )
      Yes. And after they've added all that extra weight it will still be less than the wings chosen for some other country's retarded white space elephant.
  • Old news? (Score:5, Informative)

    by AZScotsman ( 962881 ) on Wednesday April 29, 2009 @11:32AM (#27760747) Journal
    McDonnell-Douglas did this almost 20 years ago - the DC-X (http://en.wikipedia.org/wiki/DC-X), later known as the Delta Clipper.
    • Thanks for the reminder on the DC-X. I forgot that thing existed, much less actually worked (for takeoff and landing, getting out of the atmosphere wasn't attempted).
    • Didn't the clipper use liquid fuel? IIRC that was its downfall when it blew up on the landing pad when one of its feet didn't deploy and it tipped over.

      Either way, I would urge anyone trying to crack this tech to review the clipper's failure before continuing.
    • So what? Thunderbird 3 (and 1 come to that) did this way back in the '60s.

  • by Kozar_The_Malignant ( 738483 ) on Wednesday April 29, 2009 @11:36AM (#27760795)
    It seems pretty inefficient to carry the fuel mass for the retro rocket braking all the way up out of the gravity well into orbit and then back down into the gravity well so you can use it in the last kilometer of the flight. There doesn't seem any way to stop at a gas station on the way down, but maybe they are planning on lifting the fuel to orbit on non-reusable tankers, which also seems inefficient. In something like this, inefficient equates to really fucking expensive.
    • by OolimPhon ( 1120895 ) on Wednesday April 29, 2009 @11:46AM (#27760941)

      From TFA, the fuel is solid. Not easy to refill from tankers.

    • Re: (Score:2, Interesting)

      by arielCo ( 995647 )

      It seems pretty inefficient to carry the fuel mass for the retro rocket braking all the way up out of the gravity well into orbit and then back down into the gravity well so you can use it in the last kilometer of the flight.

      In other words, spend additional energy to take more energy up with you, which you will spend dissipating all of the energy you gained going up.

      That, or to keep taking advantage of the viscous gas you'll find on the way down to brake, where available. If you want precision, then you add a bit of chemically-generated thrust to steer. Where there's not enough gas (Mars and smaller), gravity may be weak enough to make the DC-X approach add up.

      • by vlm ( 69642 )

        That, or to keep taking advantage of the viscous gas you'll find on the way down to brake, where available.

        Oh, they're doing that... Its not like you'll decelerate from orbital to rest in just 600 meters above the surface. Heck I don't know if you'd decelerate from orbital to reset going 600 meters below the surface.

        I did enjoy the funny slashdot headline, if you emphasize the word "may" as in possibly or maybe.

    • by evanbd ( 210358 ) on Wednesday April 29, 2009 @12:05PM (#27761199)

      Your choices are rockets, parachutes, wings and landing gear, or a variety of weird and exotic options (like deploying helicopter blades; see the Roton concepts). There are a variety of reasons to prefer rockets to parachutes (and vice versa). The rockets are likely somewhat heavier than the parachutes and their deployment system, but I suspect the weight difference is small enough that the decision would likely be made on the basis of operational advantages (like being able to do a landing on solid ground instead of the ocean easily).

      The American space program seems to be of the opinion that everything should be as light weight and efficient as possible, without regard to other criteria. The Russians, on the other hand, have a long history of being willing to build larger, heavier, less efficient rockets in order to make operations easier. Personally, I think the Russian approach is better -- the correct figure of merit to optimize is not liftoff weight, but cost. If you can develop, build, and/or operate more cheaply by spending more weight on the problem, that's a win in my book.

      • Your choices are rockets, parachutes, wings and landing gear, or a variety of weird and exotic options (like deploying helicopter blades; see the Roton concepts). There are a variety of reasons to prefer rockets to parachutes (and vice versa). The rockets are likely somewhat heavier than the parachutes and their deployment system, but I suspect the weight difference is small enough that the decision would likely be made on the basis of operational advantages (like being able to do a landing on solid ground instead of the ocean easily).

        This is where you have to weigh the cost of the additional weight of rockets vs. parachute with the cost of having a carrier battle group standing by to pluck the astronauts out of the water. The Russian technique of just pointing the capsule at a wide expanse of steppe and sending out helicopters to retrieve the crew makes a lot of sense, far cheaper.

      • by hey! ( 33014 )

        Speaking as a totally ignorant (and thus opinion-entitled) person, I'd like to know why you couldn't combine parachutes and rockets. I'm imagining something like a powered paraglider.

        My ignorant mind can think a of a number of apparent advantages to that over rockets alone.

  • High-G landing? (Score:4, Interesting)

    by cdrguru ( 88047 ) on Wednesday April 29, 2009 @11:38AM (#27760811) Homepage

    Let's see, how fast might the ship being going when the landing system kicks in? Falling from orbit to the ground is going to produce a lot of velocity to bleed off in apparently a very short time. The shuttle uses both atmospheric braking and S-turns to bleed off velocity and still lands pretty darn fast.

    It sounds like this just falls without a chute. I'm not going to do the math, but even if it is subsonic at 800m, you are going to have to brake like mad at the end. 10G braking? 20G doesn't sound like it would be outlandish. OK, so it is a short period of time and with solid-fuel rockets it is just one pulse. But it sounds like it would be ohe heck of a pulse.

    • Re: (Score:3, Interesting)

      Something is amiss here. The energy to stop a falling box of people is APPROXIMATELY* the same energy is takes to get it up to where it fell FROM.

      If this could REALLY work as described, we wouldn't need a whole stinking stage to get the box o'humans UP into space. Email me when this works. If it doesn't, I'll hear about it.

      *Yes, the atmosphere drags both ways, but the speed it gains from falling 100,000m to 800m is less than what it would lose punching through the atmosphere.
      • Re:High-G landing? (Score:5, Insightful)

        by Waffle Iron ( 339739 ) on Wednesday April 29, 2009 @01:29PM (#27762295)

        Capsules don't just plummet vertically through the atmosphere. They spend most of the reentry going almost horizontally bleeding off speed. Most of them also angle the heat shield so that they get a good deal of lift, and they "fly" for a more gentle reentry.

        In any case, a capsule must slow down to less than hypersonic speeds before deploying a parachute. Otherwise the parachute would burn up and/or be ripped to shreds.

        Once a capsule is going slowly enough to put out a chute, it doesn't have all that much kinetic energy. Small retrorockets would be sufficient to stop it instead.

      • by sjames ( 1099 )

        Even a simple capsule doesn't just fall. It's quite common for them to gain some lift from their attitude as they reenter. That is, even without wings, the reentry path is not ballistic.

        Keep in mind, the energy to get people into orbit isn't just the gravitational potential energy to raise them to their final altitude, they also need to be accelerated at a tangent to the Earth's surface to achieve orbit. Much of that energy is what is converted to heat during reentry.

        The other factor is that on ascent, the

      • Re: (Score:3, Insightful)

        Something is amiss here. The energy to stop a falling box of people is APPROXIMATELY* the same energy is takes to get it up to where it fell FROM.

        If this could REALLY work as described, we wouldn't need a whole stinking stage to get the box o'humans UP into space. Email me when this works. If it doesn't, I'll hear about it.

        You missed one crucial factor here: terminal velocity [wikipedia.org]. An object falling down to Earth does not accelerate indefinitely, but only until the force of air resistance (which, naturally, grows as speed increases) becomes large enough to offset the gravity completely - at that point, the speed is constant. So you only need to be able to brake from that to whatever is safe for touchdown.

        I've no idea what the terminal velocity of this thing would be (it depends on both its mass and profile), but to give some idea

    • Ok, so the design is based upon rockets, but does it mean that it uses *no* aerodynamic braking at all? I don't know a whole lot about aerodynamics, but I remember from physics class the discussion of drag and terminal velocity. Is it possible that the shape of their vehicle has a relatively slow terminal velocity, so that the rockets don't have to do *that much* braking at the end? Not that I'm saying that I think even requiring a small amount of retro-rocket braking is a good design, but it seems like may

      • Re: (Score:3, Interesting)

        by evanbd ( 210358 )
        I suspect you're absolutely correct. Killing your orbital velocity on rockets alone is almost as hard as getting there in the first place. In fact, if you take the weight of the Apollo heat shields and the amount of delta-v they provide during reentry, you find they get an Isp of around 7000s -- compared to numbers in the range of 260-450 for bipropellant rockets. Heat shields are so vastly superior for the problem that you'd be insane not to use them.
      • Re: (Score:3, Informative)

        by jbb1003 ( 514899 )

        The energy to stop a falling box of people is nowhere near the same energy it takes to get it up to where it fell from when you're dealing with high speeds. Aerodynamic resistance is signficant even on a bicycle at 30mph, never mind a space reentry behicle.

        The atmospheric drag does work both ways. But on the way up, a rocket presents an aerodynamically efficient profile - i.e pointy bit first. On the way down reentry vehicles go what you might call butt first, presenting the most aerodynamically *inefficien

        • Re: (Score:3, Informative)

          by JSBiff ( 87824 )

          I think I know what you're talking about. I remember when I was young, going to some sort of space museum (I think it was part of the NASA facility near Cleveland, OH), and they had a space capsule (well, it might have just been a replica - don't remember if it was real or now). But, the capsule was presented 'detached' from the rocket, and it had a very wide, slightly rounded 'bottom', which they said during re-entry orients itself towards the ground, so all the air is colliding with the large surface-area

        • Re: (Score:3, Interesting)

          by treeves ( 963993 )

          [Pointy end first = most aerodynamic] is not necessarily true.
          Why do submarines have the big round end in front and the pointy end at the rear?

      • Ok, so the design is based upon rockets, but does it mean that it uses *no* aerodynamic braking at all?

        I'm sure it does. Hard to imagine that they could carry enough fuel to rely solely on the rockets for braking.

        But they still need to land. Since you're moving relatively slow at this point (but still fast enough to kill your crew) you can't airbrake with your vehicle body. At this point you have to deploy a system that works at relatively slow speeds. Most spacecraft rely on parachutes, sometimes supplemented by the extra cushioning of an ocean landing. But this doesn't give you a lot of control over how yo

      • by vlm ( 69642 )

        Is it possible that the shape of their vehicle has a relatively slow terminal velocity, so that the rockets don't have to do *that much* braking at the end?

        Yes, and not only that, you can take an off the shelf survivable roll cage and crunch zone design from a race car, and build the capsule around it. So, if the rocket doesn't work, the vehicle is an utter total loss, but the crew walks away basically unscratched, more or less.

    • by RobertB-DC ( 622190 ) * on Wednesday April 29, 2009 @11:52AM (#27761021) Homepage Journal

      It sounds like this just falls without a chute. I'm not going to do the math, but even if it is subsonic at 800m, you are going to have to brake like mad at the end. 10G braking? 20G doesn't sound like it would be outlandish. OK, so it is a short period of time and with solid-fuel rockets it is just one pulse. But it sounds like it would be ohe heck of a pulse.

      You're missing the point, though. Gravity is an *acceleration*. These guys will be *decelerating*. You know, like zero gee is zero acceleration? Since they'll be slowing down, they won't feel a thing. It's genius!

      (I can feel the karma draining now...)

      • Re: (Score:3, Informative)

        by Aranykai ( 1053846 )

        Lol, you accidentally the whole equation.

      • by Plekto ( 1018050 )

        You're missing the point, though. Gravity is an *acceleration*. These guys will be *decelerating*. You know, like zero gee is zero acceleration? Since they'll be slowing down, they won't feel a thing. It's genius!

        ****
        I wonder if the impact will be over with quicker than their neurons can fire? I suspect that if it fails, yes, they won't feel a thing.

    • by Rolgar ( 556636 )

      I think the space shuttle orbits earth 16 times a day (90 minutes/orbit), or about 27,000 kph. Terminal velocity of the capsule is much lower (less than 300kph) than the speed of the capsule in orbit, which is why the reentry from space is so hot, because the spacecraft is losing speed as it reenters, not picking up speed. This is the same speed that was gained when the craft originally launched into orbital. Link

      If you compare this to a fighter taking of from an aircraft carrier, a catapult changes the

    • 2174.749 f/s (Score:3, Interesting)

      Based on this NASA app: http://www.grc.nasa.gov/WWW/K-12/airplane/termv.html [nasa.gov]
      • The Apollo Command Module weighed 12773lbf/5806 kg, but the app only takes 10000 lbf.
      • Diameter of 3.9m, 12' 10" yields frontal area of 128.5 square feet.
      • WILD A55 guessing the Drag Coefficient at 1.0 (based on the page: http://www.grc.nasa.gov/WWW/K-12/airplane/shaped.html [nasa.gov])
      • Dropping from an altitude of 100000ft (ha!)

      2174.749 f/s SOMEONE has the wrong terminal velocity. Are we sure this isn't a way to eliminate political disside

  • I can't imagine that a parachute wouldn't still be used for the initial descent. This plan also requires comparatively large amounts of rocket fuel to be launched and brought back down and is a potential safety risk in the event of a malfunction on landing. In the case of the survived malfunctions with the Soyuz system, many have been sheer luck but some of the survivability has to be attributed to the simplicity of the design.

  • Just making new capsules without the rockets may be just as cost effective. That is all that you are saving from the trip.

    • Just making new capsules without the rockets may be just as cost effective. That is all that you are saving from the trip.

      I think you're forgetting something. Is it just as cost effective to make new cosmonauts? Or maybe you planned to have them make some UHALO jumps. Master Chiefs away!

      • by sjames ( 1099 )

        Nah, the cosmonauts are just instructed to jump up the instant the capsule hits the ground. What could go wrong?

  • That's got to be some serious thrust and precision. Actually, if this works, without intertial dampeners, the people inside are going to be goo on the floor ;)

  • During the formal defense of the project, one high-ranking official skeptical of the rocket-cushioned approach to landing reportedly used an unprintable expletive to describe what was going to happen to crew members unlucky enough to encounter a rocket engine failure a few seconds before touchdown."

    It would accidentally the whole crew!

  • Don't judge (Score:5, Funny)

    by oldhack ( 1037484 ) on Wednesday April 29, 2009 @12:00PM (#27761117)
    I think this will work. It's used extensively on giant robots in Japanese cartoons.
  • Not completely new (Score:5, Informative)

    by Urban Garlic ( 447282 ) on Wednesday April 29, 2009 @12:07PM (#27761217)

    The existing Soyuz TMA capsules also have "soft-landing rockets", they're used just at the point of touchdown to cushion the landing. Of course, the TMAs also have a parachute, so it's less of a problem if the landing rockets fail.
    Interestingly, the very first Soyuz TMA had all kinds of other problems [jamesoberg.com], but the landing-rocket part actually worked.

  • Astronauts that have heat-shielded spacesuits and pop-out hang-glider wings gliding back to terra firma.
  • Yea! We get the Buck Rogers rocket ships that land on their fins. Do we also get the evil galactic empires too? And the super-weapons of EE Doc Smith?

  • Is it just me, or does this thing look a lot like the Orion module? Hmm... first the Buran which looks like the shuttle, now this thing that duplicates Orion. The Russians should try their hand at making a small, passenger only ship, like the HL-20 or the X-38, or the Mig Spiral.
  • Synchronize (Score:2, Interesting)

    by djdbass ( 1037730 )
    I don't know the first thing about rocket science, so let me ask the crowd here.

    How do you synchronize the firing of 12 solid fueled rockets?
  • I think while this is fairly useless for landing on earth. It could be more useful for landing on other planets. If we are landing on a planet without much atmosphere or some harsh environment parachutes could be rendered useless. Ignoring that repacking parachutes outside of a cleanroom using robots is not really done. So parachute re usability is down. As well parachutes do not allow you to chose a very specific landing point even here on earth where we know pretty much everything about the wind. As well
  • by roystgnr ( 4015 ) <roy AT stogners DOT org> on Wednesday April 29, 2009 @01:09PM (#27762077) Homepage

    Don't get me wrong, I'm all in favor of spaceships landing on a tail of fire, "the way God and Robert Heinlein intended!" But rocket-powered landings on Earth are a questionable engineering decision even when you get to reuse some of the liquid-fueled rocket engines that you already needed for liftoff and already wanted to recover intact. If you instead have to add extra weight to your upper stage for single-purpose solid rockets of lower ISP, it seems even more dubious.

    And that's before you get into the issue of "solid rockets" and "precision". Even designing a liquid-fueled rocket with adequate throttle control for a gentle landing isn't easy. (It's like brain surgery! Or possibly like some other appropriate metaphor!) But at least throttling liquid fuel consumption rates is possible. Solid rockets basically have just three settings: "off", "on", and "kaboom".

    • by roystgnr ( 4015 )

      liquid-fueled rocket engines

      Let's say "liquid-propellant rocket engines" instead. In a paragraph contrasting spaceflight "the way God and Robert Heinlein intended" to "rockets of lower ISP", it was almost sacrilegious of me to assume that even the former would be wholly chemically fueled.

  • I thougt (Score:3, Interesting)

    by codepunk ( 167897 ) on Wednesday April 29, 2009 @02:16PM (#27762925)

    I thought the Ruskie's where smarter than that, sounds like something nasa would propose. Russia has always had a successful space program
    because they use well tested and simple engineering. Just a capsule it goes up and parachutes back to the ground, no wings no crazy rocket
    assisted landing. The higher the component count and complexity the more room for failure.

  • Might I suggest that the Russians call the new system the "Spacecraft Precision Lander And Transporter". The name might not be the greatest, but the acronym says it all.

  • I feel bad for the guy that cleans the people soup this makes in the crater.

    Ron White might say. This will take them all the way to the crash site.

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