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The Military Technology

Researchers To Build Underwater Airplane 263

coondoggie writes to tell us that DARPA seems to still be having fun with their funding and continues to aim for the "far out." The latest program, a submersible airplane, seems to have been pulled directly from science fiction. Hopefully this voyage to the bottom of the sea is of the non-permanent variety. "According to DARPA: 'The difficulty with developing such a craft come from the diametrically opposed requirements that exist for an airplane and a submarine. While the primary goal for airplane designers is to try and minimize weight, a submarine must be extremely heavy in order to submerge underwater. In addition, the flow conditions and the systems designed to control a submarine and an airplane are radically different, due to the order of magnitude difference in the densities of air and water.'"
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Researchers To Build Underwater Airplane

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  • Isn't this the same exact kinda thing that Steve Fossett et-al were building (completed?) - as covered previously on Slashdot?
    • Re:Steve Fossett (Score:5, Informative)

      by Anonymous Coward on Monday October 06, 2008 @02:57PM (#25276085)

      Linky [slashdot.org]

      Steve Fossett's Unfinished Project
      Posted by kdawson on Sunday October 05, @02:36AM
      from the ocean-flying dept.
      Transportation Science Technology
      MazzThePianoman writes "Steve Fossett left behind a secret vessel project called the Deep Flight Challenger. Fossett was funding the development of a winged submersible being designed by Hawkes Ocean Technologies in California. The intent was for the vehicle to be capable of travel to the very bottom of the ocean -- the Mariana Trench, more than 11,000 meters beneath the surface. 'It would have dramatically, dramatically opened the oceans for exploration. It would have been a game changer,' said Graham Hawkes, the designer. Testing had been completed at Department of Defense facilities. Field testing was only four weeks away when Fossett's untimely death, a year ago, put the project on hold." Hawkes Ocean Technologies owns the design but the vehicle itself is owned by Fossett's estate.

    • Re:Steve Fossett (Score:4, Informative)

      by Anonymous Coward on Monday October 06, 2008 @02:58PM (#25276121)

      No, this is an airplane that can also be a submarine (and surface vessel). Fossett was financing a sub that "flew" underwater.

      • Re: (Score:2, Insightful)

        by Anonymous Coward

        All submarines 'fly' underwater. Take a look at the control surfaces of a submarine sometime. The cross section is similar to that of the wing of an airplane. A submarine is similar to a dirigible in that it can either adjust its ballast or use its control surfaces with a propulsion system to control its depth.

        • Re: (Score:2, Troll)

          Not really. "Flying" requires using aerodynamic or hydrodynamic properties to provide lift or buoyancy. Submarines use ballast to sink, then expel the ballast to surface. Both airplanes and submarines use similar structures for controllability, but a submarine doesn't fly any more than a zeppelin does.

          If you think about for a minute, you will see why a heavier-than-water submarine that flies is a really bad idea. However, I have seen designs for positive buoyancy submersibles that fly down,
          • What is a flight? (Score:3, Interesting)

            by pato101 ( 851725 )
            The definition of flight, as I studied at flight mechanics, is the motion through a single media or lack of media.
            Airplanes fly through the air
            Zeppelins and balloons fly through the air
            Submarines fly through the water
            Space-ships fly out of atmosphere
            Ships do not fly because their motion is in between two media
            Cars do not fly (except for some instants, as it is the case of Rally cars jumping :P ), since their motion is between two media.

            From an engineering point of view, submarines use buoyancy force
          • Utterly Wrong (Score:5, Informative)

            by titzandkunt ( 623280 ) on Monday October 06, 2008 @08:10PM (#25279255)
            I love the self-assurance of the ignorant. Quite cute, really...

            I work with ex-submariners. One of the reasons that they hated and feared a real reactor SCRAM was that the sub was essentially relying on its forward motion to maintain it's depth.

            Yes, it was negatively buoyant, but the slight upward pitch of its planes enabled it to "fly" through the water. Supposedly, you get much more responsive control that way, rather than wallowing in the water while you wait for tanks to fill or empty. Very important, when you're trailing an aggressive Russian sub...

            When the reactor shuts down and the screw stops turning, the damn thing will sink until the control team get the tanks set for neutral or positive buoyancy. Not a comfortable time as the boat heads down and the hull groans and creaks and everyone starts to wonder if there's enough high pressure air in reserve to blow the tanks.

            Mainly OT, but by God and by golly, major navies do FLY their subs.
            • Just like the self-assurance of the supremely arrogant. /. is sounding more like Digg every day...sigh.

              On to my point...

              Fine -- so a slight negative buoyancy is augmented by some flying with the dive planes. Nevertheless, a submarine, unlike an airplane is *not* dependent upon forward motion to rise to the surface. A submarine, unlike an airplane, primarily uses ballast and or air to at least approximate the buoyancy of an equal volume of water. Whether or not it *augments* this equilibrium with fo
              • Re: (Score:3, Insightful)

                by rtb61 ( 674572 )

                The deepest diving subs do not use air to surface but lighter than water hydrocarbons, as at higher pressure the air compresses more, displaces far less water, so they can only make one trip to the bottom, then drop ballast and rise to the surface. An incompressible positively buoyant craft can make many trips to the bottom, the catch is the deeper it want to go, the more force is required ie. the faster in must fly through the water, oddly similar to planes.

                Of course to correct your other error, you cou

    • First thing that came to mind for me is from the old UFO series http://en.wikipedia.org/wiki/SkyDiver [wikipedia.org]

      The idea of JATO (or is that RATO) assisted launches from underwater would make for some interesting dynamics, yet I think that space borne items will be of far more value in the long term, its not like you can't drop from about anywhere up there and end up where you want to be while a submersible is subject to being easily interdicted

      • by BCW2 ( 168187 )
        Easily interdicted? If you can find it, maybe? As an old Submarine Sailor I promise, we can run faster than anyone can hunt.
    • Re: (Score:2, Funny)

      by Anonymous Coward
      Isn't this the same exact kinda thing that Steve Fossett et-al were building (completed?)

      Yep. The first test pilots were John Denver and John F. Kennedy Jr. Apparantly the tricky part is coming back up...
    • ...and his Diving Seacopter. I'm sure it was a product of Swift Enterprises.

      I really did want to be Tom Swift Jr. when I was young. Unfortunately I ended up looking more like Chow Winkler.

      I don't really know who were part of the team that was Victor Appleton III, but they came up with a lot of intriguing gadgets and ideas to wrap the book's formula around when I was in the 6th grade. Jet submarines, flying cars ("Ultrasonic Cycloplane", lovely great words you could chew on), giant robots, quite a range r

  • Crazy DARPA (Score:5, Funny)

    by Anonymous Coward on Monday October 06, 2008 @02:53PM (#25276047)
    Airplanes underwater??? This is crazy talk! Next they will wants subs that fly!
  • by thrillseeker ( 518224 ) on Monday October 06, 2008 @02:55PM (#25276057)
    to build a flying submarine - I mean after all, if we made a brick fly (an old saying about the F-4 Phantom).
    • Re: (Score:3, Interesting)

      Would the nuclear B-36 [archive.org] count? It wasn't nuclear-powered but it did have an operational power-producing nuke running in it when it was flying, with the intent to develop it into a fully nuclear-powered aircraft using a General Electric HTRE nuclear aircraft engine. It was as heavy as many subs and you had to crawl around through it, using a rope-pulled trolley to get from the front to the back.

    • RTFA. that's what previous attempts have tried to do, and failed.

      though i don't see how they're going to have any better luck trying to get a plane to act as a sub. perhaps if they created a vehicle that could radically reconfigure its shape to suit the two different environments it might have a chance of success. but their current design just seems like it would perform poorly in both environments.

      as the article stated, the two goals are diametrically opposed. you can't create a single design that will

      • Re: (Score:3, Interesting)

        by Talderas ( 1212466 )

        For extra credit, create a vehicle that can fly, go into space and submerge to the deepest portions of the ocean.

  • by Anonymous Coward on Monday October 06, 2008 @02:57PM (#25276097)

    I don't have anything to say, but everybody else is posting stuff with "Steve Fosset" as the title.

  • TPM (Score:4, Funny)

    by pak9rabid ( 1011935 ) on Monday October 06, 2008 @02:58PM (#25276105)
    Sounds like a few too many people at DARPA liked 'The Phantom Menace' a little too much.
    • Sounds like a few too many people at DARPA liked 'The Phantom Menace' a little too much.

      More like "The Incredibles".

      In particular: The scene where Mr Incredible is being flown to Syndrome's island-of-military-tech-fabrication in an automated plane which (for no discernible reason) lands by smoothly "flying" into the water and cruises underwater into an underground/underwater hanger which drains and fills with air.

      • Re: (Score:3, Informative)

        by Blakey Rat ( 99501 )

        Does Phantom Menace even have a flying submarine? It has a regular submarine...

        But anyway, obviously the correct reference is to the submersible squadron from Sky Captain and the World of Tomorrow. Der. Plus: Angelina Jolie!

  • by mknewman ( 557587 ) * on Monday October 06, 2008 @02:58PM (#25276109)
    http://en.wikipedia.org/wiki/Image:Flying_Sub.jpg [wikipedia.org] Someone's imagination is running wild. If DARPA is giving them money then it's time to turn them off.
    • A wild imagination is a good thing. See this piece of aluminum from a few years back: http://lifeboat.com/images/transparent.aluminum.jpg [lifeboat.com]
    • by LWATCDR ( 28044 )

      The navy did look at this in the 1960 because of that movie/TV show.
      The Japanese did build subs that carried aircraft.
      As to how impractical?
      Well think about the SLCM and the Sub-Harpoon.
      Both are very close to flying subs. They just go bang and don't land.

      My guess is they are looking at a drone and not a manned aircraft. With modern composites it might be very do able.

    • Re: (Score:2, Redundant)

      If DARPA is giving them money then it's time to turn them off.

      The patients have been running the asylum at DARPA for at least 8 years now. I watched a doc on the Military Channel about a DARPA conference. The doc was in the context of "cool new weapons at the DARPA" tradeshow or whatever they call it.

      They actually had this idiot (he acted like one of those dopey "regular guy" characters in a cheesey commercial) who had money somehow. He talked about how, one day he was watching Frankenstien with static e

    • If DARPA is giving them money then it's time to turn them off.

      If you don't realise that the Seaview and related technology is the product of the Nelson Institute of Marine Research [nimr.org], then you need to deliver any geek creds you have to the nearest recycling depot. The Institute is funded by Admiral (ret.) Harriman Nelson.

  • Let's See. (Score:5, Funny)

    by Kid Zero ( 4866 ) on Monday October 06, 2008 @02:59PM (#25276129) Homepage Journal

    Rocks sink, and Rocks Fly. Problem Solved!

  • by neoform ( 551705 ) <djneoform@gmail.com> on Monday October 06, 2008 @03:05PM (#25276189) Homepage

    I'm not sure, but I believe those "underwater airplanes" already exist.. and are called "submarines".

  • by circletimessquare ( 444983 ) <circletimessquare&gmail,com> on Monday October 06, 2008 @03:06PM (#25276209) Homepage Journal

    study up on flying fish [wikipedia.org] and flying squid [wikipedia.org]

    then dabble in cormorants [wikipedia.org] and water beetles [everythingabout.net]

    once again, mother nature was here first and has a lot to teach us about where to start

  • by XSpud ( 801834 ) on Monday October 06, 2008 @03:07PM (#25276215) Homepage
    Before they go too far with the designs, DARPA might want to check their figures for the densities of water and air. Last time I checked they differed by a lot more than "an order of magnitude" and I'd think this might be important.
    • Re: (Score:3, Interesting)

      by qkslvr ( 594310 )
      Thank you. I hate it when someone uses "an order of magnitude" as a synonym for "a lot" just to sound smart.
    • Re: (Score:2, Funny)

      by Anonymous Coward
      I'll have an order of magnitude and a side effect, please. To go.
    • Not to mention the main difference between subs and airplanes apparently being weight, which is a horribly stupid and flat-out wrong statement.

      Want more weight? Bring some water into the machine, compress some air so you can blow it out later, and you're set. The MAIN difference between airplanes and subs is that airplanes are made to operate in 0.5-1atm of pressure (yes, I know it's an archaic unit of measure... it's easier than actually looking this stuff up). Just 30ft down, a sub has to handle 2atm o

  • This game was called X-COM 2 : Terror from the Deep.
  • by smellsofbikes ( 890263 ) on Monday October 06, 2008 @03:12PM (#25276275) Journal

    Supercavitation [wikipedia.org] would allow submarines to move at supersonic (with reference to water) speeds while submerged, and dogfight underwater [space.com] like WWI aircraft did in the air. If they can come to a complete stop they'd be silent and invisible, just floating there, then fire up the engines and go back to moving faster than ship-based sonar would be able to detect them. There's already a supercavitating torpedo [wikipedia.org]. People who design targets -- I mean aircraft carriers and destroyers -- must be worrying about this.

    • You beat me to it. This is the only way you could "have your cake and eat it, too".

    • Re: (Score:3, Informative)

      by Thelasko ( 1196535 )
      I thought of the supercavitation thing too. It appears that's not what DARPA is looking for. From TFA:

      Speed: The speed of the platform in each mode of operation must allow the system to complete a tactical transit (1000 nm airborne,100 nm surface ,12 nm sub-surface) trip in less than 8 hours. This 8 hour time must include any time required by the platform to reconfigure between modes of operation.

      Although, I think a supercavitating submarine is way cooler, they are basically looking for a seaplane [wikipedia.org] that c

    • Re: (Score:3, Interesting)

      by Chris Burke ( 6130 )

      Supercavitation would allow submarines to move at supersonic (with reference to water) speeds while submerged

      Wait, you mean faster than the speed of sound under water? If that's what you meant, no way, we can't make things move that fast in air, so how can an object basically traveling in an underwater air bubble move that fast? The fastest torpedo listed on the wiki page is a 2004 German torpedo which it says reaches 800km/h, which is 3/4ths the speed of sound in air, which is itself around 1/5th the spe

      • I haven't found any references online but I've read stuff about people getting projectiles -- not self-powered -- travelling faster than the speed of sound in water for short distances. I wish I could find stuff online.
        But you're right: *enormous* amounts of power needed. However, if it could move faster than a ship could detect it, that'd be a *big* deal, so the question is probably one of when, not how.

    • by evanbd ( 210358 ) on Monday October 06, 2008 @04:02PM (#25276861)
      Unfortunately, the *massive* power requirements of such operation mean that they require a rocket engine for propulsion -- and rockets have a rather substantial appetite for propellant. (BTW, the Shkval only goes at ~200 knots, not supersonic.) The shkval is largely rocket propellant, and even so only gets 7-13km range. There are almost certainly improvements possible, but I'd be surprised if you could build a sub that supercavitated for a long enough range to be useful as a sub and not just a missile / torpedo.
    • by CodeBuster ( 516420 ) on Monday October 06, 2008 @11:55PM (#25280879)

      Supercavitation would allow submarines to move at supersonic (with reference to water) speeds while submerged, and dogfight underwater like WWI aircraft did in the air.

      The last I heard any vehicle making use of supercavitation is not able to turn (or at least not very quickly) at supercavitating speeds while underwater. It would be like a car turning suddenly in a long, narrow, and straight tunnel through solid rock (with similar results). The Skvahl [wikipedia.org] torpedo, for example, is said to have this limitation (i.e. it is a straight shot weapon with no ability to correct course once it has been fired and is up to speed).

  • My inexpert take. (Score:3, Interesting)

    by MaxwellEdison ( 1368785 ) on Monday October 06, 2008 @03:12PM (#25276279)
    How about this, a rear propulsion planwhich the pilot operates in a counterbalanced globe at the nose. The airplane slows down to a minimum airspeed and inserts the nose and flips over, the pilot's globe rights itself and the planes control surfaces are inverted. The fusalage takes on water to neutral bouyancy and the plan controls as if it were upside down. I'm sure this is completely unfeasible and I hope someone will explain why. The main problems I see are 1.) Slowing the plane enough that 'insertion' doesn't rip it apart. 2.) The pilot seizing up during this maneuver which would go against all of their piloting instincts. 3.) Control systems designed for air travel would be completely inefficient/infeasable in an aquatic environment. Did I forget anything else?
    • You'd probably need to land first like a regular floatplane. Then you could tilt your wings and control surfaces upside-down rather than tilting the whole craft end-over-end. You'd need to account for structural integrity (at least of the cockpit), and how you'd make something strong enough to take your target depths safely light enough to fly.

  • Well, the "flying" submarine bit has been around for awhile [deepflight.com], but adding the air part certainly does add a twist.
  • Let's not be illiterate.

    • "try TO minimize weight", godsdamnit
      Let's not be illiterate.

      If you can't read it, that makes you the illiterate person. ;)

  • by Kupfernigk ( 1190345 ) on Monday October 06, 2008 @03:16PM (#25276321)
    I went for a job interview in the early 80s at a military systems company. I had been working on real-time hardware/software for control of a system in two and half dimensions. They wanted someone to work on a control system which was vaguely similar, but they were very cagey about exactly what. I had a major disagreement with the interviewer about some questions he asked me. On the way out we passed a room where someone was coming out of the door and I saw briefly on the wall a wooden mock up of something that looked very like a manta ray.

    I then put two and two together and got five, because I realised that the disagreement arose because the interviewer did not expect the operating temperature range of the hardware to exceed more than about 25 degrees C - which made sense if it was for use in sea water.

  • Hey, I can make any plane a submersible. Granted, there's not much you can do with it after that point but hey, you were the one who were vague about the specifics!

    Anyone else getting flashbacks to that old game Subwar 2050?

  • Why am I paying my tax money for this? Can someone explain? They rip off the taxpayer to the tune of $500 billion every year (although only a fraction of that is DARPA) and then build something ridiculous with no prospect of adoption, ever, or wage wars under false pretenses.

  • by egyptiankarim ( 765774 ) on Monday October 06, 2008 @03:19PM (#25276355) Homepage
    "We're taking over 150 atmospheres of pressure!"

    "How many atmospheres can this ship take?"

    "Well, it's a spaceship, so I'd say anywhere between 0 and 1."
  • by .sig ( 180877 )

    All I can say is "Why?" - This really does sound like a stupid(tm) idea to throw money at...

    Note - I'm not being rhetorical, I'd really like a [good] answer...

    • If this actually does work (which I doubt it will, for any sort of reasonable cost and performance parameters -- this is why DARPA is just a huge waste of money), it'll be of great use on the battlefield.

      The biggest danger to aircraft at sea is surface-to-air missiles. An aircraft that could submerge briefly could dodge incoming missiles by simply dunking under water and waiting for them to impact on the surface (in probably the wrong spot, since they'd also lose radar tracking).

      Likewise, a torpedo launched

  • by Skapare ( 16644 ) on Monday October 06, 2008 @03:28PM (#25276443) Homepage

    I'm waiting for the sonic boom.

  • by Rayeth ( 1335201 ) on Monday October 06, 2008 @03:29PM (#25276453)
    since when is "fuckofftags" a useful tag?
  • by Chris Burke ( 6130 ) on Monday October 06, 2008 @03:32PM (#25276483) Homepage

    They're saying how the requirements for submersibles and aircraft are diametrically opposed. That's good! If they were only kinda in opposite directions, that'd be a challenge. But calling on my vast electrical engineering knowledge (and what is mechanical engineering but electrical engineering with molecules instead of electrons?), I can tell you this is easy. What do you do if you discover that your current is diametrically opposed to what you want? That's right, you flip the terminals around, and bam your current is spot on!

    So, using the same principle. In air you want the plane light and lift high because gravity means the natural tendency of the plane is to go downward and you want to go up. Underwater, gravity turns into buoyancy and your plane would naturally want to go up when you want it to go down. This sounds like our current problem -- we have a plane that flies perfectly in air, but in water goes the opposite direction of what we want. So what do we do? Yeah, we just flip it. Now the "lift" of the wings is pointed down. All you need then is an engine that works in air and water, and either a crew compartment that rotates to stay vertical, or sturdy straps and training for pilots to maneuver while upside-down. Done!

    I just but the reversed-wing thing is actually used in some high speed submersible. Exercise on how to make it work in either direction above/below water left as an exercise for the DARPA grantee.

  • All it needs is nuclear power and a cool shape...

  • I remember seeing a mini sub that was neutrally buoyant and used its 'wings' to 'fly' in the water.

    Sounds like proven tech to me.

  • Does it come with Angelina Jolie wearing an eyepatch? Are they going to do helicarriers next?

  • It's an interesting capability, but rather specialized.

    What DARPA apparently wants is an aircraft with modest underwater capability, just enough to submerge to snorkel depth. It's intended to carry a Navy SEAL team. (They use the term "operators", which includes a range of special-ops people, but if it's an open-ocean job, they'll probably be SEALs.)

    SEALs already have various rubber boats and mini-subs, and those can be deployed from helicopters, existing submarines, and surface craft. So why the nee

  • by TheBigDuck ( 938776 ) on Monday October 06, 2008 @04:18PM (#25277011) Homepage
    When I was in the Navy, my Captain was a submariner and my XO (2nd in command) was a helicopter pilot.

    These two guys didn't get along.

    In one (of many) knock down drag 'em out verbal exchanges the two had, the Captain yelled at the XO,
    "There are more helicopters at the bottom of the sea then there are submarines in the sky!!"
  • http://bcliffe.com/subs/FS1.html [bcliffe.com]

    I need one of those models...

  • ...of the undeniable fact that there's nothing under the sun that man cannot conceive, that Gerry Anderson [wikipedia.org] hasn't thought of already.
  • by codeButcher ( 223668 ) on Tuesday October 07, 2008 @03:42AM (#25282465)
    that will fly like a lead zeppelin. What next? Roll-down windows for submarines?
  • by SmallFurryCreature ( 593017 ) on Tuesday October 07, 2008 @08:04AM (#25283991) Journal

    This type of object exists, we HAVE flying submaringes, they are called BIRDS. Diving birds are NOT constrained by their weight. Their problem is their lungs. Several spieces swim very well under water and can even go straight from flying to submerged.

    If birds can do it, so can man.

    The trick is to stop thinking of this object as an old fashioned submarine and accept that modern submarines FLY under water. They use their "wings" to control their movement, not their weight.

    The biggest challence is re-configuring the wings. Birds can do this easily but swing-wing is out of fashion for a reason. A swing wing that can survive a dive is going to be a major piece of engineering.

    Another challenge is getting from one method of propulsion to the other. Birds of course use the same engine and switch effortleslly between legs and wings for power, can humans do the same? Have a single engine that can power motion in air and underwater?

    There is however one part of the requirement that might make it more difficult. I think this aircraft is intended for the insertion of seal units quickly without having to worry about air defences. For the seals to disbark from the aircraft underwater it would have to be going very slow or even be motionless. An aircraft that is light and uses negative lift to remain submerged would shoot up like a cork if it stopped.

    Key problems:

    Power source that can operate underwater.

    Two modes of propulsion for air and water.

    Switching quickly between modes and both modes not interfering with the other, for instance propellors would probabbly smash during a power dive.

    Being able to remain motionless underwater and also submerged.

    If it wasn't for the last requirement the trick would be fairly simple, "just" a plane that has positive lift in the air, negative lift under water, super-cavitation speeds to be able to shoot up out of the water with enough speed to remain airborne and a system to switch seamlessly between air and water propulsion.

    Do-able. But remaining motionless underwater adds a whole new trick. Suddenly you can use your speed and re-use your wings to remain underwater, you need to alter your weight.

    Mind you, I wonder if we at slashdot are not overcomplicating things. What DARPA is looking for is a way to insert seals with minimal detection.

    What about an 'ordinary' sea plane that instead of sitting above its floaters can sink beneath them? Imagine an ordinary plane with floaters attacked sticking out the sides and below. It lands on the water as all seaplanes do but then the floaters rotate above the fuselage allowing to disappear beneath the waves. The fuselage opens, allowing sea-water inside removing most of its lift. The floaters act like miniature subs and can submerge to an extent. This aircraft is not about setting records, it has to operate near the coast anyway so can't go to deep in any case.

"If you lived today as if it were your last, you'd buy up a box of rockets and fire them all off, wouldn't you?" -- Garrison Keillor