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Experimental Fuel-Cell Airplane Begins NASA Test

Posted by timothy on from the aloft-a-lot dept.

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."

10 of 40 comments (clear)

  1. So what? by Smidge204 · · Score: 3, Insightful

    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.

    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 (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=

    1. Re:So what? by barakn · · Score: 2, Insightful

      It or something like it has the potential to do research in Mars's atmosphere.

      --
      "I'm so moist I'm sticking to the leather." -Kermit the Frog on The Late Late Show
    2. Re:So what? by Descartes · · Score: 2, Interesting

      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.

    3. Re:So what? by WolfWithoutAClause · · Score: 4, Informative
      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.

      --

      -WolfWithoutAClause

      "Gravity is only a theory, not a fact!"
    4. Re:So what? by The+Creator · · Score: 2, Funny
      Yes, well, cost per kg of a satellite is atleast $4600/kg


      Too easy. :)


      $4600/kg or ~$10,000/lb


      See, we keep telling you the metric system has benefits. :)

      --

      FRA: STFU GTFO
    5. Re:So what? by Bob+Bitchen · · Score: 4, Informative

      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 and look at Aerovironment too.

      --
      http://tinyurl.com/3t236
  2. Re:great by WolfWithoutAClause · · Score: 2, Informative

    We aren't going to run out of oil. We're only going to run out of petrochemicals. There's always going to be oil; you can run diesel engines on vegetable oil for example.

    --

    -WolfWithoutAClause

    "Gravity is only a theory, not a fact!"
  3. convert to wind power by js7a · · Score: 3, Informative
    Correct: we have a 400 year supply of coal, and it needs to last us 400,000 years. We are already halfway through our oil and converting coal to synthetics is much more expensive than using hydrogen from wind power.

    If the entire planet converted to wind power in 30 years, it would take another 300 years to remove the extra heat from the last 300 years of fossil fuel use. Until we get control of it, we won't be able to pick an optimal CO2 concentration value for the planet.

  4. more NASA Dryden links by js7a · · Score: 3, Informative
    Helios prototype home page

    May 29 Press Release

    June 7 Press Release

    If you click on that Kauai picture from the Dryden home page, 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.

    1. Re:more NASA Dryden links by PPGMD · · Score: 2, Interesting

      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.