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Robotics Technology

Liquid Hydrogen UAV 157

Posted by samzenpus from the impulse-power dept.
From the same company that brought you the Wasp MAV, Aerovironment announced yesterday that they have successfully completed the world's first liquid hydrogen powered Unmanned Aerial Vehicle (UAV) flight tests. From the press release: " AeroVironment's Global Observer High Altitude Long Endurance (HALE) platform will be able to operate at 65,000 feet for over a week with a flexible payload-carrying capacity of up to 1,000 pounds." Applications include government and military surveillance operations, communication relays, and the potential for persistent real-time imagery of wildfires, hurricanes, and other natural disasters. More pictures here.
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Liquid Hydrogen UAV More

Liquid Hydrogen UAV

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  • You forgot! (Score:4, Funny)

    by metlin ( 258108 ) * on Wednesday June 29, 2005 @09:46PM (#12947185) Journal
    Applications include government and military surveillance operations, communication relays, and the potential for persistent real-time imagery of wildfires, hurricanes, and other natural disasters.

    You forgot Gate Recon!!!

  • Think of the possibilities... (Score:5, Funny)

    by KennyP ( 724304 ) on Wednesday June 29, 2005 @09:48PM (#12947201)
    Hover over a nude beach and take hi-res pictures. It's every /.er's dream!

    Visualize Whirled P.'s

  • What I'm wondering is (Score:4, Interesting)

    by suitepotato ( 863945 ) on Wednesday June 29, 2005 @09:49PM (#12947207)
    how does it compare to the solar ones they wanted to fly which are supposed to stay up indefinitely? Also, are there applications for missions on Mars? Pretty neat accomplishment though.

    • Re:What I'm wondering is (Score:5, Interesting)

      by jd ( 1658 ) <imipak@ y a hoo.com> on Wednesday June 29, 2005 @10:24PM (#12947397) Homepage Journal
      Solar UAVs for spying would have a problem - if they're over the clouds, the camera sees nothing but clouds. If they're below the clouds, the solar panel sees nothing but clouds. Either way, it's not really that useful.


      The hydrogen-powered UAV would be good for exploring hurricanes over a prolonged period of time, as it could sit in the clouds near the eye and just monitor stuff, rather than having to return to base to refuel. That would mean weather centers would get some excellent continuous data, which might improve their forecasts of these types of system.


      For Mars, there are no clouds to contend with, so solar panels would work a great deal better overall. EXCEPT in sand-storms, where they'd not only be useless during the storm, they'd be so etched up at the end that they'd be useless afterwards, too. If you plan on studying Martian storms up-close, carrying your own fuel would have some major benefits. (Remember, they'd need to carry their own oxygen, too, though.)


      A potential civilian use for this kind of technology would be in fighting wildfires. The late Red Adair, and others like him, fought fires with high explosives, but those tend to leave a lot of very eco-unfriendly residue.


      On the other hand, if you were to have a remote-control aircraft with a large amount of liquid hydrogen aboard, it could potentially have much the same effect (deprive the fire of oxygen) but with a lot less environmental impact.

      • "For Mars, there are no clouds to contend with, so solar panels would work a great deal better overall. EXCEPT in sand-storms, where they'd not only be useless during the storm, they'd be so etched up at the end that they'd be useless afterwards, too. If you plan on studying Martian storms up-close, carrying your own fuel would have some major benefits. (Remember, they'd need to carry their own oxygen, too, though.)"

        The bigger problem with one of these on Mars is the thinner atmosphere. It's a lot harder
        • And, no, I'm not really that smart. I read about it in PopSci or something.

          You mean, NASA engineers do more than that? :)

          Seriously, yes, you are right - any aircraft relying on lift would have substantially more problems and would require a very different design. In all probability, you'd be looking at straight wings (for maximum lift) that were perhaps ten times those you'd need for high-altitude gliding on Earth, and you'd be looking to glider experts, not "traditional" pilots, to fly the damn thing

      • Solar UAVs for spying would have a problem - if they're over the clouds, the camera sees nothing but clouds. If they're below the clouds, the solar panel sees nothing but clouds. Either way, it's not really that useful.

        Don't be silly. These things cruise at 65,000 feet, higher than anything but storm clouds. And they're designed to stay up for a week at a time. Unless a storm stays over one spot for three to four days, these things will eventually do their jobs. The U2 flies so high that the pilot mu

      • Re:What I'm wondering is (Score:1, Insightful)

        by Anonymous Coward
        Dumping liquid hydrogen on a fire to extinguish it, as you seem to be suggestiong, is not the smartest idea... Firstly, and least significantly, much of the hydrogen would vaporise very quickly in 1 atm pressure and 20 degrees temperature. Secondly, hydrogen is highly flammable.
        • I think you just got (and missed) both points... one way to extinguish a forest fire is oxygen deprivation. Often, a highly flammable substance is burned to suck oxygen out of the area and thus extinguish the fire. The plus side to using liquid hydrogen is that any excess fuel that doesn't burn up will almost instantly vaporise and leave the area, not leaving unwanted incindiaries lying around, as sometimes happens with traditional explosives.
      • Red Adair did not fight wildfires with explosives. Jeez.

        He fought oil well blowouts...and when an oil well goes, a few pounds of explosives residue won't make a damn bit of difference in the "eco-unfriendly residue". JEEEEEEEZ.

      • Re:What I'm wondering is (Score:5, Insightful)

        by DieByWire ( 744043 ) on Thursday June 30, 2005 @01:10AM (#12948097)

        Solar UAVs for spying would have a problem - if they're over the clouds, the camera sees nothing but clouds. If they're below the clouds, the solar panel sees nothing but clouds. Either way, it's not really that useful.

        Clouds aren't the issue. There are lots of other ways to look at or listen to things than visible light. The problem with the solar version is payload. Helios had to be incredibly light to fly on solar power - it had a 247 ft wingspan, yet weighed only 1500 pounds. It broke up in flight two years ago. AV's Global Observer has a 1000 pound payload.

        The hydrogen-powered UAV would be good for exploring hurricanes over a prolonged period of time, as it could sit in the clouds near the eye and just monitor stuff

        For endurance you need high aspect ratio wings. Think U-2, think Steve Fossett's round the world flight. To survive in the clouds near a hurricane, you have to be built like a P-3 - short, stubby, stronger than hell wings. This thing might fly high over a hurricane, but it would never survive in one.

        A potential civilian use for this kind of technology would be in fighting wildfires. The late Red Adair...

        Red Adair fought well fires.

        On the other hand, if you were to have a remote-control aircraft with a large amount of liquid hydrogen aboard, it could potentially have much the same effect (deprive the fire of oxygen) but with a lot less environmental impact.

        Now there's a great idea. Starve the fire of oxygen by having all of the oxygen combine with a bunch of free hydrogen, creating nothing but water vapor... oh, and a little bit of heat. Heck, you could just use a KC-135 and dump raw gas or jet fuel on it for the same effect, no new technology needed.

        • My apologies for my sarcasm... after posting, I realized that when you said wildfires, you meant well fires - not the multi thousand acre monsters that most of us think of when we see the word 'wildfire.'

          I'm not sure if liquid hydrogen could produce an appropriate oxygen deprivation type blast or not (I have my doubts, but I still have ten fingers and almost no explosives experience), but surely there would be far more cost effective ways to do it than by sacrificing a large, expensive UAV. The environmen

        • Re:What I'm wondering is (Score:3, Interesting)

          by jd ( 1658 )
          Now there's a great idea. Starve the fire of oxygen by having all of the oxygen combine with a bunch of free hydrogen, creating nothing but water vapor... oh, and a little bit of heat. Heck, you could just use a KC-135 and dump raw gas or jet fuel on it for the same effect, no new technology needed.

          The heat would be immaterial, with no oxygen present, and the shockwave would displace air in the surroundings.

          True, you'd cause a ruddy big hole in the ground. On the other hand, I think I'd prefer to deal

          • The heat would be immaterial, with no oxygen present, and the shockwave would displace air in the surroundings.

            Um... you're not an engineer, right?

          • The reason why explosives work to put out well fires is that the fuel source is relatively confined and thus it is fairly easy to separate the fuel from the oxygen long enough to snuff out the fire.

            In a forest fire the fire is completely surrounded by additional fuel. Between the heat of the explosion and the burning embers and such that would undoubtedly be thrown in to the air, you would be more likely to spread the fire rather than put it out.

            Besides, I would think that in many cases forest fires may

      • infrared cameras see through most clouds just fine, and you can choose the right wavelength of radar to penetrate them too.

        why else do you think so many satellite weather images are in false colour but still show details on the ground?
    • There's a number of Mars flying issues. So far I consider X-Plane - Mars Chronciles [x-plane.com] the definitive layments guide.

      Basics:
      There is only 1% the atmosphere of earth.
      ~33% gravity.

      Trying to stop is pretty much impossible. Propellers are pretty much useless.
      On the plus side, rocket hydrogen gliders should work pretty damned well... least till they have to land.

  • Useful for spying (Score:3, Insightful)

    by Dancin_Santa ( 265275 ) <DancinSanta@gmail.com> on Wednesday June 29, 2005 @09:56PM (#12947233) Journal
    I understand the need for good intelligence in making national security policy, but flying spyplanes over the airspace of your friends and enemies alike isn't going to win you any brownie points, and as the US has already experienced with the U2 (the crashed plane, not the band that's selling out), one crashed spyplane can lead to a hell of a lot of trouble.

    Spying is a nasty business, and I guess it's a necessary evil, but the person in charge of announcing new toys at Aerovironment must be completely braindead. Someone at the State department ought to go have a talk with those good folks.
    • U2 sold out a long time ago, what are you talking about...

    • Re:Useful for spying (Score:3, Informative)

      by joeljkp ( 254783 )
      I'm at this conference right now (it ends tomorrow). Everything here is about spying. Every display booth here is about high resolution camera systems, hardened data storage, remote sensing, and a miriad other things useful for spying, whether it be over the next hill or over another country.

      Even the student competition that I'm a part of has spying as its primary objective (autonomous navigation and target recognition).

      • But it should be mentioned that those same type of techniques used in spying could be used for scientific observation. For instance, the typical UAV competition has, like you said, a target recognition efvent where the UAV is able to identify a target on the ground with maybe some other rules. Distance from target, size of target, image returned, etc. But couldn't that same technology just as easily be used to find someone lost in the wilderness?

        Another example would be this particular HALE project mention
    • What exactly would you expect the State Department to say to these folks?

      1) All airspace above Flight Level 600 ("60,000 feet") is outside the territorial control of any country by international agreement.

      2) Most first and second world countries have ready access to all the spy satellite data they can handle. What's the big deal here?

      3) This UAV is probably not the first of its kind, nor will it be the last. Drones like this have been researched for the last couple decades. I'd be surprised if there w
    • U2 (the crashed plane, not the band that's selling out)

      I am curious; on what basis do you claim U2 is selling out?

  • Solar energy (Score:3, Interesting)

    by William Robinson ( 875390 ) on Wednesday June 29, 2005 @10:00PM (#12947266)
    The wings look really big. Why dont they think about including solar panels on the wings?

  • Article Unclear (Score:4, Interesting)

    by compmanio36 ( 882809 ) on Wednesday June 29, 2005 @10:02PM (#12947275)
    So, is this vehicle running a fuel cell type setup? Or is there some other way of using liquid hydrogen?

    Either way, is this something that can be put into cars? It seems if they can keep an airplane up for over a week, a car would really benefit from this technology.

    Of course, cars tend to get into accidents a bit more often than unmanned planes. Would hydrogen be as volatile in a liquid state?

    • Judging by the array of little props on the leading edge of the wing, this UAV is probably Hydrogen Fuel-Cell powered.

      However, if I recall, Hydrogen Fuel Cells, which produce water as a by-product would actually contribute to ozone depletion because water acts like a greenhouse-gas at altitudes over ~27,000ft.

      Luckily, these little things probably don't produce all that much water. - Unless they build one each to spy on everyone in the world! ;-)
      • I think you'll find that ozone depletion and the greenhouse effect are two completely separate things. (only similar in that both are considered to be a bad thing for the environment)

        Whether used in a HFC, or just burnt in a combustion engine, any process which combines Hydrogen and Oxygen to produce energy is going to produce water.
      • An ideal hydrogen fuel cell takes in H and O, resulting in H20, electricity, and heat. A real HFC also emits some unburned H and a bit of CO and CO2 left over from incomplete catalyzation (maybe 10ppm if we're efficient).

        H20 is staple, so it won't react with O3. CO, CO2 and free H all work to create Ozone in smog, so this may apply at high altitude as well.

        Ozone depletion is mainly the work of Nitrogen oxides, which when expelled from your car or Whippet [erowid.org] catridges, survives the year or so it takes to difus

        • I should add, the main source of Carbon in HFC exhaust would be from using petrol or natural gas as fuel. If Aerovironment is using pure Hydrogen, then the tiny bit of environmental gaseous Carbon oxides sucked into the system would barely register.
  • Is this technology suitable for use in commercial aircraft? The Airlines are taking a beating right now, a large part to their own incompetence, but the $60 a barrel prive for oil is driving jet fuel costs through the room. It seems like if Boeing or Airbus could get some of this type of engine technology working in large commercial aircraft, they could make a killing.

    • Re:What about Commercial Aircraft? (Score:1, Informative)

      by Anonymous Coward
      The trouble is that producing hydrogen needs oil either directly or to produce electricity. It's also harder to store and transport. There aren't any real benefits to the airline industry.
    • Unfortunately, you've got the Hindenburg Effect, which kind of makes Joe Public a little wary of flying with too much hydrogen. Yes, it's not a valid concern, as H can be stored a lot safer than high-ocataine jet fuel, but doesn't make it any more popular.
    • Nah! If I can just get my rubber powered balsa prototypes to scale up I'll have 'em beat.

      KFG
    • the $60 a barrel prive for oil is driving jet fuel costs through the room. It seems like if Boeing or Airbus could get some of this type of engine technology working in large commercial aircraft, they could make a killing.

      The problem is that the closest supply of gaseous hydrogen is on Jupiter. So here on earth, it's artificially manufactured from natural gas, whose price correlates very closely to the price of oil.

    • I could see this sort of technology acting as a power assist for commercial aircraft, but it impractical.

      First of all you have the weight, the craft is as skinny as rail, and only carries 1000 pounds. That is in the sub-feather-weight class of airplanes. I doubt that this same powertrain could drive a plane full of cargo and/or passengers.

      You also have the functional question. This technology is for staying in the air for a week. It does not have what the airlines need. Passengers are looking to get

    • Re:What about Commercial Aircraft? (Score:4, Insightful)

      by Sparohok ( 318277 ) on Thursday June 30, 2005 @01:01AM (#12948068)
      What makes you think hydrogen has any advantages over kerosene (jet fuel) for commercial aircraft? Hydrogen has a lower energy density, it's far more expensive, and it's much harder to store. The only (debatable) advantage is environmental and that hardly outweighs the crushing disadvantages.

      The press release is mighty short on details, but I assume this UAV uses electric motors. Presumably liquid hydrogen and a fuel cell is lighter than batteries. It's a great solution if your goal is to fly very slowly for a long, long time. Not so good if you want to move half a million pounds at 600mph.

      Martin

  • torrents and mirrors galore! (Score:4, Informative)

    by xbmodder ( 805757 ) on Wednesday June 29, 2005 @10:07PM (#12947300) Homepage
    pictures: http://mirrordot.org/stories/aaf0c842dfe20788ff7a5 5f10aff4b6d/index.html [mirrordot.org]
    The main page:
    http://mirrordot.org/stories/d1d8af49f65278e926452 b7286f69bcb/index.html [mirrordot.org]

    other mirror:
    http://xbmodder.us/www.aerovironment.com/ [xbmodder.us]

    my picture mirror (don't hit this) only do this if you can't get the torrent:
    http://xbmodder.us/www.aerovironment.com/global-ob server/go_pictures.htm [xbmodder.us]

    torrent:
    http://xbmodder.us/global-observer.torrent [xbmodder.us]

  • Liquid Hydrogen? (Score:4, Funny)

    by DarkHelmet ( 120004 ) * <mark&seventhcycle,net> on Wednesday June 29, 2005 @10:12PM (#12947320) Homepage
    Oh the humanity!
    • is one more really good album cover.

      I believe the RIAA is suffering from the lack of hydrogen-fueled airships. All they have now are rock stars looking old, male hip-hop artists looking mean, and female hip-hop artists looking ... as female as possible.

      Give me a snapshot of burning hell falling from the sky once in a while, and maybe I'll pay $19.95 for your amelodious drivel.

      And I'm not even a Led Zep fan.

    • You're thinking about gasseous hydrogen.
      This is liquid hydrogen, it's perfectly safe!
      It's not only too cold to burn, it would also extinguish itself (being a liquid).

      < /humour >
    • Mostly because if liquid hydrogen explode it does it with great force, as the late Ben Rich found out when he did research for a proposed LH2-fuelled reconnaissance plane. Note that in his book Skunk Works Rich noted that when he visited a university where students did research on LH2 there were a number of holes in the wall caused by LH2 explosions--and that's with a very small amount of LH2 being used in lab experiments!

      That's why when Challenger exploded in 1986 it did it with the force of a tactical nu

  • More on Defense Tech (Score:4, Interesting)

    by noahmax ( 534339 ) on Wednesday June 29, 2005 @10:12PM (#12947326) Homepage
    There's more on this and other long-range UAVs over at Defense Tech [defensetech.org] -- including a solar-powered drone that just set endurance records.
  • Damn.. that will be some nice fireworks!

  • What about my gas helium UAV? (Score:5, Funny)

    by geekwithsoul ( 860466 ) <geekwithsoul&yahoo,com> on Wednesday June 29, 2005 @10:20PM (#12947367)
    Big deal! I took my kid to the circus the other day and got him a gas helium Unmanned Aerial Vehicle for free. They just handed it to him on a string, we untied the bottom, and whoosh! . . . it took off and flew all by itself.
  • Thank God for this UAV, I hope they patch bf2 with this new uav that stays longer in the air.
  • But just when are we gettingliquid hydrogen powered cars? Seriously, I'm freaking fed up with paying 20$ a gallon on gas. Maybe an infinitely available resource would be cheaper.
    • The answer is never. Hydrogen in cars is very bad idea - impractical, dangerous and very expensive.

      $20 a gallon? I do not know what country you live in but the current US prices are at around $2.40 - and that is retail at the pump, after taxes, on weak greenbuck. If you are actualy getting milked $18 on a galon, the source of your problem is in your government. (Even if you measure in UK gallons which are bit larger, your price is outrageous).

      There is more coal than oil and coal-based gas at double of the
      • word economy would collapse if the gas would cost twice as much as it is now.
        oil is not just used to run car,
        its used to generate electricity, to make plastic, to run many factories.
        an analogy would be the human body: which contains 70% water.
        now, you don't need to loose all 70% to die, 10-15% would be enough.
        read this fine article for more about it.
        http://www.lifeaftertheoilcrash.net/ [lifeaftertheoilcrash.net]

        any resource with an unlimited supply is better that any resource with a limited supply in the long run.
        sooner than later
    • What do you think they burn to get the energy to isolate the hydrogen, dood?
    • Gas is about $2.50 per gallon in the USA at the moment, I think. In the UK it's somewhere around 85 pence a litre, which works out as $5.79 a gallon.
    • But just when are we gettingliquid hydrogen powered cars? Seriously, I'm freaking fed up with paying 20$ a gallon on gas. Maybe an infinitely available resource would be cheaper.

      An 'infinitely available resource'? The closest place where it is available in substantial quantity is Jupiter.

      Hydrogen on earth is usually produced from oil, just like gas, because that is cheapest. It is also possible to produce it from other sources, just like it is possible to produce fuels similar to gas from other sources,
    • Mind you the silver paint on that flaming blimp is now used as rocket fuel.
    • From parent's link:


      CONCLUSIONS:

      Careful investigation of the Hindenburg disaster verified the opinion of the engineers on the Hindenburg and proved that it was the flammable aluminum powder filled paint varnish that coated the infamous airship, not the hydrogen that started the fateful fire.

      In searching for a hindemburg picture regarding the use of hydrogen, he provided us with information explicitly telling us that it was NOT the hydrogen but something else that made it so dangerous.

      DOH! :-P

  • Insulation (Score:3, Insightful)

    by Muhammar ( 659468 ) on Wednesday June 29, 2005 @10:54PM (#12947543)
    I would like to know how they solved the problem of cryo storage of liquid hydrogen. Sure the air temperature and thermal conductivity at high altitudes is decreased but this can help only so much. I just dont see how they can keep it at minus 259C for one week. Dewar made of plastic? Pressurizing it would not help because at -240C hydrogen stops being liquid regardless of the pressure.

    My guess is that one big tank fills up most of the pregnant-looking belly. The craft may need some teflon coating on the surface to prevent ice buildup. Also, it is apparent from the video that landing it in even modest crosswind will be tricky business (as with any large-wingspan ultralight).
    • well if it's light enough there's the easy way.

      turn off engine, deploy parachute.

    • Re:Insulation (Score:3, Interesting)

      by LordMyren ( 15499 )
      The coolant chamber for the Saturn rocket was reported to be so efficient it would loose only 2.5 degrees over a ten year span, or some similarly perposterous metric. Course, that was space, but we are exceedingly good at erecting some magnificient thermal barriers.

      Hydrogen has suh an energy content that for a significant sized ship (read: not this tiny thing)dumping a little bit of fuel into energy to refridgerate would not be in any way a problem. The only real problem as far as I see is safety issues

    • Re:Insulation (Score:3, Informative)

      by aXis100 ( 690904 )
      Easy.

      You let some of the liquid hydrogen evaporate (called boil off gas) - that draws thermal energy from the remaining liquid like an evaporative cooler. You can then consume that boil off gas in your turbines/fuel cell/whatever.

      This method is commonly used on LPG tankers.

  • How about a purely scientific use? Week long telescope surveys of space. Would be high enough to lose atmospheric blurring and short enough to collect lots of data, return to earth, then be reconfigured for another mission.

    • Re:High Altitude Telescopes (Score:3, Informative)

      by Anonymous Coward
      You would take a nice, stable telescope off of the ground and put it on a craft that vibrates like hell and your pictures would come out pretty bad (not to mention that your telescope would be so small that it wouldn't have near the resolving power that the ground scope would have).
  • I'm guessing not one of these Aholes in the military saw Terminator. Jeeez AH-nold give 'em a jinglejangle and tell 'em how it ends!

  • Still not my favorite UAV... (Score:3, Interesting)

    by cryptocom ( 833376 ) on Thursday June 30, 2005 @02:16AM (#12948313)
    ...my favorite was the D-21 drone, code named Senior Bowl/Tagboard...originally launched off the back of an SR71 Blackbird, but later launched from the wing of a B-52 bomber. not much endurance, but holy shit could that thing fly...
    PERFORMANCE
    Maximum speed: Mach 3.3
    Range: 3,400+ miles
    Service Ceiling: ABOVE 90,000 ft.
  • the potential for persistent real-time imagery of wildfires, hurricanes, and other natural disasters

    How many of you thought "Cool. Real-time imagery!"? ;-)

  • It's better to say that UAV stands for "Unoccupied Aerial Vehicle." That way you can't just get a woman pilot and pocket the DARPA dollars.
  • will Angelina Jolie be aboard? Will she be wearing an eyepatch? Because the eyepatch is pretty hot in a weird, pirate sort of way.

  • I was getting all excited when I interpretted UAV as Urban Assualt Vehicle. That I could use.

  • One thing I am a little confused about is why hydrogen? My understanding was that the stuff you throw into your car offers much more bang for the volume. While it is nice that this UAV is, uh, eco friendly, why did they go with hydrogen instead of a petrochemical? I figure there must be some advantage (better power to weight ratio?), but I don't see it. Hydrogen packs less of a punch then petrochemicals and requires a sturdy and much heavier tank to hold. So why hydrogen?
  • In addition to Hydrogen's advantage of a very high energy to weight ratio, its very low temperature could be used to cool an airplane's superconducting electric motor to the required operating temperature. Such motors can be 1/3rd the weight of conventional motors for the same power, as well as being significantly more efficient.

    Perfect for small UAVs patrolling battle sites.

    Imagine a Beowulf cluster of these!

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