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Science Technology

Experimental Fuel-Cell Airplane Begins NASA Test 40

gilgsn writes "Planenews.com has a NASA press release from their Dryden Flight Research Center about the first large fuel-cell powered airplane to fly. The Helios prototype took-off Saturday at 8:43AM from the Hawaiian island of Kauai, using solar panels to power its 10 electric motors for takeoff and during daylight portions of its 20-hour shakedown flight. As sunlight diminishes, Helios switched to a fuel cell system to continue flight into the night. I wonder how long it will be before fuel cells are used on homebuilt experimentals."
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Experimental Fuel-Cell Airplane Begins NASA Test

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  • So what? (Score:4, Insightful)

    by Smidge204 ( 605297 ) on Sunday June 08, 2003 @01:13PM (#6144255) Journal
    Not to be a wet blanket, but while Helios is really neat it's not terribly useful. Only 762 pounds [nasa.gov] of payload available, minus mandatory equipment. For the cost to build and operate the vehicle it clearly doesn't have any commercial potential. It might be cheaper than launching a satellite in some cases, if it can provide the same functionality, but that's about it.

    The biggest problem is that it's still more or less a solar powered craft -- and solar energy just doesn't have the density to do anything useful and still be mobile.

    Although... maybe something like this could make a reasonable alternative to those Broadband Broadcasting Balloons [slashdot.org] (say that three times fast!), since these craft can fly at higher altitudes and make roam to areas where they may be needed more.

    =Smidge=

    • Re:So what? (Score:3, Insightful)

      by barakn ( 641218 )
      It or something like it has the potential to do research in Mars's atmosphere.
      • Re:So what? (Score:2, Interesting)

        by Descartes ( 124922 )
        I'd think the atmosphere on mars is too thin for this kind of aircraft. I suppose if you take the lower gravity into account it might make a difference, but I doubt it.
      • If you're going through the trouble of sending something all the way to mars to do high-altitude whatever, it'd be cheaper and easier to send something that orbits the planet instead of trying to land something like this (much larger, much more fragile and probably heavier) on the surface, then unpack it, then try to get it to take off. Last I checked there aren't any airports on Mars.

        If you want high-altitude air samples, you can make little lander things that will sample the air and send back the results
      • I'm pretty sure that the solar density at Mars is too weak to be useful for this application. Mars solar density is 589.2 W/m^2, versus Earth's 1367.6 W/m^2, a ratio of .431 (source [nasa.gov]).

        Solar cells would have to get a lot more efficient to put this contraption on Mars.

    • Re:So what? (Score:5, Informative)

      by WolfWithoutAClause ( 162946 ) on Sunday June 08, 2003 @05:00PM (#6145506) Homepage
      Not to be a wet blanket, but while Helios is really neat it's not terribly useful. Only 762 pounds of payload available, minus mandatory equipment. For the cost to build and operate the vehicle it clearly doesn't have any commercial potential. It might be cheaper than launching a satellite in some cases, if it can provide the same functionality, but that's about it.

      Yes, well, cost per kg of a satellite is atleast $4600/kg (~$10,000/lb, and that's to low earth orbit which is only over the horizon for a few minutes at a time- GEO sats are visible all the time but are 3x more expensive). But you usually don't get these satellites back again, and if anything goes wrong up there, you're screwed. With Helios you can bring it down, fix it and send it back up.

      The biggest problem is that it's still more or less a solar powered craft -- and solar energy just doesn't have the density to do anything useful and still be mobile.

      Well, it's 1.5kw/m^2. That's more power than a 1 bar electric fire. Ok, so solar panels at the moment are at most getting to around 40-60% efficient (for lab samples, small production/expensive ones are more like 20%, cheap ones are 10% or so), but that's still quite a bit of power.

      Although... maybe something like this could make a reasonable alternative to those Broadband Broadcasting Balloons (say that three times fast!), since these craft can fly at higher altitudes and make roam to areas where they may be needed more.

      Yes, very probably would work. That's the point of the fuel cell; they can keep it up there 24 hours a day; previously it was coming down at night. 762 pounds of radio equipment should be plenty; provided it doesn't suck too much juice. It might even be possible to build a passive system- just bounce the radio waves off the underside of the vehicle.

    • Re:So what? (Score:4, Informative)

      by Bob Bitchen ( 147646 ) on Sunday June 08, 2003 @07:07PM (#6146144) Homepage
      Not to be a wet blanket, but while Helios is really neat it's not terribly useful.

      You're not a wet blanket, just wrong. They have already completed HDTV trials, lots of other applications to follow. Cell towers will be replaced by these. Cell towers have been unpopular in most areas. No one wants to live next to one. These can be easily launched and can be made cheaply.

      It might be cheaper than launching a satellite in some cases,

      It's definitely cheaper than launching a satellite

      For the cost to build and operate the vehicle it clearly doesn't have any commercial potential

      Oh really, can you provide some facts to support that claim? You simply just don't know what you are talking about. Have a look at Skytower Global [skytowerglobal.com] and look at Aerovironment too.

      • Your forgetting the most important factor: Obnoxious citizens.

        You know these people... they move into a house right next to a rural airport and immediately start bitching about the sound...

        Celltower: I don't want that ugly thing near my beautiful house. It's going to ruin the view.

        Helios: I don't want that ugly thing circling over my house. What if it crashed in the school yard, think of the children you bad person!!!

        You see the pattern.... also know as BANANA (Build Absolutely Nothing Anywhere Near A
    • These are almost flying cars, with no fuel bills.

      Now if we could only reduce the wingspan, buy bottled hydrogen (double thermos tanks with internal revacumation pumps are expensive) at the hardware store, and agree on a common transponder format, then we would be halfway there.

  • by js7a ( 579872 ) * <james@@@bovik...org> on Sunday June 08, 2003 @10:06PM (#6147142) Homepage Journal
    Helios prototype home page [nasa.gov]

    May 29 Press Release [nasa.gov]

    June 7 Press Release [nasa.gov]

    If you click on that Kauai picture from the Dryden home page [nasa.gov], look at the window title: the payload is denoted as "amphitech radar" -- which I surmise means something that weighs about the same as what they think they would need for a sufficiently suitable unmaned AWACS drop-in replacement.

    • The May press release [nasa.gov] is interesting:

      "After testing on this system is finished this summer, we will focus on development of a fully regenerative system that could fly up to six months or more,â he added. Del Frate said a production version of the Helios with the regenerative fuel cell system is of interest to NASA for environmental science, the military and AeroVironment for various roles, primarily as a stratospheric telecommunications relay platform.

      The latter role will be the focus of a flight

    • The only real problem that I see with this is the fact that it's maximum altitude is 100,000 (subtract 10% to get the real world numbers), and the operational altitude would be 50,000 to 70,000 feet.

      The problem is that many thunderstorms can easily reach 60,000 ft, and this craft doesn't look like it would do too well in a storm.
      • this craft doesn't look like it would do too well in a storm.

        First, what makes you think it can take more than an AWACS? There is only one way to find out. It's uninhabited, so we can know for sure what it will take, instead of having to approximate the question.

        A gentleman from Dryden phoned me this morning to explain that the night flight didn't happen because there were two leaks, one on the fuel cell air compressor, and another on the cooling system for the air compressor. They were probably rel

        • AWACS, if you mean the Huricanne Hunters, first off those guys fly very sturdy C-130's that are given extensive inspections before they enter. And they know the risks of their jobs, they know that they might die.

          But normal military and civilian aircraft avoid thunderstorms when they can, the down drafts and up drafts of those storms can be more than even a fighter jet can handle.

          It remains to be seen how well this craft will do in a storm, but I highly doubt that NASA would risk it, because the wing flex
          • the wing flex in normal flight, is pretty high.

            Granted, the crescent wing flex is what gives it differential pitch control, which is another new technology it's pioneering.

            It can take a 600 lb. payload to 70,000 feet, so I'm sure that eventually fleets will be used for theater radars. Keeping them out of the storms should be easy, because it can exceed 150 mph at those altitudes.

            It's not so much a saftey issue as a cost issue. All the UAVs save the brass some very serious coin, and after combat pr

  • "I wonder how long it will be before fuel cells are used on homebuilt experimentals."--- Not long at all I think, considering you can buy a model car kit at Fry's [outpost.com] for about $100 USD [I saw it back in January for $130 USD] Now that it's dropped a bit I'll probably pick it up and play around with it.
  • You can barely get us pilots away from our beloved 100LL, it's going to be a while before I can see anyone going for an electric airplace.

Who goeth a-borrowing goeth a-sorrowing. -- Thomas Tusser

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