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New Solar Plane Plans Non-Stop Flight Around The World (bloomberg.com)

Posted by EditorDavid on from the flight-plans dept.

An anonymous reader quotes Bloomberg: [A] Russian tycoon and his Renova Group plan a record-breaking effort to send a plane around the world nonstop using only the power of the sun. If all goes well, a single pilot will fly for five days straight at altitudes of up to 10 miles, about a third higher than commercial airliners. The project isn't just a stunt. The glider-style airplane with a 36-meter (120-foot) wingspan will be a test of technologies that are set to be used to build new generations of autonomous craft for the military and business, say aerospace experts. They will fly continuously, have far greater reach and control than satellites and expand broadcast, communication and spying capabilities around the globe... "Our flight should prove that it's possible to make long-distance flights using solar energy," said Mikhail Lifshitz, Renova's director of high-tech asset development and a qualified pilot-instructor. A "flying laboratory" test-plane will be ready by year-end, Lifshitz said in an interview.
The plane will conserve power by slowly gliding down from the high altitudes at night -- without ever touching the ground. In comparison a solar plane (partially funded by Google) already circled the earth last year -- but it took 22 days, and made 17 different stops.

10 of 35 comments (clear)

  1. World record for staying awake? by Anonymous Coward · · Score: 2, Interesting

    TFA Says there will only be a single pilot. If the attempt succeeds, this will demonstrate either how someone can (legally?) stay awake for five days AND command an aircraft during that time. There will be some interesting legalities to be defined here, bearing in mind the different national regulations governing drugs, pseudo-autonomous aircraft and combining the two.

    1. Re:World record for staying awake? by fustakrakich · · Score: 2

      Really, why is there a pilot? Think of all that wasted energy spent for life support? And who wants to be stuck up there for five days?

      --
      “He’s not deformed, he’s just drunk!”
  2. Shouldn't that be by Yurka · · Score: 2

    "Our flight should prove that it's possible to make long-distance flights using solar energy if you only ever need to fly east"?

    --
    I can assure you, the best way to get rid of dragons is to have one of your own.
    1. Re:Shouldn't that be by ShanghaiBill · · Score: 4, Interesting

      "Our flight should prove that it's possible to make long-distance flights using solar energy if you only ever need to fly east"?

      One proposed use of solar planes is as communications relays, to replace satellites. They would circle the earth continuously, one trailing the previous by about 200 km. They could fly either direction, but flying east wins in both sunlight and prevailing winds (at least in mid latitudes).

      Using solar drones instead of satellites for communication is cheaper not just in launch cost, but in the cost of the electronics. Satellite electronics need to be rad-hard, but also need to be super redundant because otherwise a single bad chip can cost $100M. But with a solar drone, if there is a failure in the relay electronics, you just land it and swap out the board.

  3. Why not use airships? by Dr.+Spork · · Score: 4, Interesting

    I think it's fine to use devices in the atmosphere to relay our communications signals, but why planes? Wouldn't it be better to have some sort of a blimp with thin film solar cells on its upper surface? These could provide energy for maneuvering the various layers of moving air to maintain a reasonably constant position. Alternately, it could just be at the end of a long tether. I think that's a much more elegant way of keeping up altitude overnight.

    1. Re:Why not use airships? by Gravis+Zero · · Score: 2

      why planes? Wouldn't it be better to have some sort of a blimp with thin film solar cells on its upper surface?

      At high altitude an airship will be exposed to a lot of radiation which will quickly degrade all plastics. In an airship this will quickly lead to a hull integrity failure and require replacing the entire hull because it's under high levels of stress 100% of the time. In an airplane, even if the plastic parts have reduced integrity, it will still function even if parts of the wing begin to fleck off.

      --
      Anons need not reply. Questions end with a question mark.
    2. Re:Why not use airships? by dbIII · · Score: 2

      If only a pile of organic chemists in the 1980s and 1990s had worked on that so we wouldn't have to worry so much about the UV degradation (ie. "radiation"). Hang on - they did!
      There are probably real show stoppers with weather, buoyancy etc but you managed to squarely hit something fairly irrelevant as if deliberately testing for ignorance.

  4. Re:Capacitors! by FrankSchwab · · Score: 2

    As a spec-built glider, it would be interesting to see if they considered incorporating supercaps into the structure, for example, as the center layer of any honeycomb material. You have to carry the weight anyway; replacing or augmenting something which doesn't provide power seems like a win.

    --
    And the worms ate into his brain.
  5. Re:Capacitors! by rew · · Score: 2

    There are two things that could be important. One is power density and the other is energy density. You could express these in a per-volume measure, but in this case per-weight is important.
    Similarly, in this case, it is the ENERGY density that matters.

    For perspective, Tesla optimizes their batteries for energy density. But still they get an impressive power-density. IT seems they hit the power-limit when you do a ludicrous mode 0-60MPH. So the 0-60 time improves when you go from 85kWh to 100kWh: not only do you have a larger energy capacity, but also more power.

    Looking for numbers for a back-of-the-envelope calculation, I found an article by Deepak P Dubai that claims 2 mWh/cm^3. That would be 7.2 J/cm^3.
    I have a 10Ah 22V battery that weighs 1.2kg. If I assume a density of about 1g/cm^3, I get 666J/cm^3 for that battery. Almost a difference of a factor of 100.

    Really I could see the gap closing , but not by a factor of 100 in a few years.

  6. Re:Quick calculations... by Falconhell · · Score: 2

    From memory, The FES electric self launch system fitted to the new Alisport Silent, and LAK Mini self launching 13.5m sailplanes have 4kw/hr capacity from 2 x 15Kg LIPO packs, 22kw motor, controller and charger 20kg for an allup weight of 52kg.
    This gives very good self launch, and about 45 min range at over 60kt, depending on conditions and pilot skills.
    Cruise uses 4kw continous.
    It might be possible to use mountain wave lift to cover significant distances too, particularly useful at night, supplementing the onboard charging system, even regeneterative charging using the motor could be possible.
    The Perlan project would seem a good start to building this sort of sailplane.

    http://www.front-electric-sust...

    http://lak.lt/models/minilak/