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Solar Powered UAV to Set Aviation Endurance Record?

Posted by ScuttleMonkey on from the getting-warmer dept.

Iddo Genuth writes to mention that a group of Israeli students is hoping their latest unmanned aerial vehicle (UAV) will soon break the world aviation record for endurance that has stood for over 17 years. The piece features a short history of solar power aviation and an interview with the students.

12 of 59 comments (clear)

  1. hmm by mastershake_phd · · Score: 2, Insightful

    The work done at the Technion as well as elsewhere around the world is starting to attract the attention of the aviation industry with the hope of creating green aircrafts with a much higher endurance threshold.

    I dont really see this being applied to commercial passenger or cargo planes. Maybe ultralites.

    --
    Libertarian Leaning Political Discussion Forum.
    1. Re:hmm by h2_plus_O · · Score: 2, Informative

      dont really see this being applied to commercial passenger or cargo planes. Maybe ultralites.
      Think military, recon, and intelligence-gathering. The ability to have a drone orbit the same patch of earth for days over a target with live video feed? You could spy on the sunbathers next door without being detected for sure.
      --
      If there's one thing I won't stand for, it's intolerance.
    2. Re:hmm by DieByWire · · Score: 2, Interesting

      This doesn't have to replace traditional fuels, it can supplement them.

      While technically not impossible, it would be completely impractical.

      Solar's strength is high and slow. High, because you're actually going to get more sunlight (power) as you climb, whereas combustion engines lose power as you climb due to thinning air. (One reason why Helios was pushing 100,000 feet.) Slow, because you're using an electric motor to turn a big, slow revving prop. (Props can't get anywhere close to mach without tremendous loss of efficiency.)

      While in theory you could use the electic power to turn a ducted fan, it would never produce enough thrust to make up for it's drag and weight at airliner speeds.

      Solar's niche is high altitude, slow speed and long endurance. It will have some neat uses, but there's not enough oomph for high speed or high payload applications like jetting to Vegas for the weekend.

      --
      Never shake hands with a man you meet in a fertility clinic.
    3. Re:hmm by DieByWire · · Score: 2, Interesting

      Again, why can't you run your engines off jet fuel, and everything else (lights, radio, etc) from solar cells? Save some fuel in the process.

      Same reason you don't have solar cells on your gasoline powered car powering your electrical system - because its waaayyyy cheaper to just let the engine turn a generator. Airliners also fly during the evening, at night, and at high latitudes where the sun's angle incidence is too low for the solar panel to produce meaningful power.

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      Never shake hands with a man you meet in a fertility clinic.
    4. Re:hmm by DieByWire · · Score: 2, Insightful

      When they pull a plane to the gate, they hook it up to a power system to keep the AC, lights, etc, running, without wasting fuel. How much could be saved both fuel and electricity at the airports?

      Why don't you just put solar panels on the terminal roof then? Cheaper, no weight added to aircraft, easier to engineer, and useful when the plane's not there.

      Solar power for airplanes is a niche market - high, slow, endurance, light weight. You won't be seeing it on airliners anytime soon.

      --
      Never shake hands with a man you meet in a fertility clinic.
  2. UAVs? Long range? Oh dear! by mpaque · · Score: 3, Funny

    "... could use these small UAVs, which have a wingspan of only a few meters, to deliver biological agents to its neighbors or if transported, to other countries, including the United States."
    -- Secretary of State Colin Powell in a presentation before the U.N. Security Council, February 5, 2003

    Oh, snap! These are just students trying to set a new endurance record. The purity and essence of our natural... fluids are not at risk. Surely we must issue the recall code immediately.

  3. Low-cost Satellites by writerjosh · · Score: 4, Interesting

    This is why solar powered flight is important:

    "Called the Zephyr, it's an aircraft that can fly continuously using nothing but solar power and "low drag aerodynamics". The combination of solar panels on the upper wing surface and rechargeable batteries allows Zephyr to be flown for many weeks and even months. The first flight trial of the Zephyr were conducted recently by QinetiQ in White Sands Missile Range, New Mexico.

    Two aircraft were flown for four and a half and six hours respectively, the maximum flight times permitted under range restrictions. The maximum altitude attained was 27,000 feet above sea level. The ultra-light aircraft is designed to fly at altitudes as high as 132,000 feet (25 miles/40km), above normal commercial air-lanes and most weather.

    QinetiQ believes that stratospheric platforms will rapidly become commercially viable and revolutionize future communications. High altitude platforms of this sort could provide a cheaper alternative to satellites in remote areas and developing countries. They can also enable observation of natural disasters and humanitarian crises."

    http://www.treehugger.com/files/2006/03/solar_powe red_p_2.php

    --
    Health Insurance Quotes
    1. Re:Low-cost Satellites by nsayer · · Score: 4, Informative

      Among the advantage to stratospheric platforms over geostationary orbit satellites:

      1. Antenna aiming isolation. The same downlink frequency can be shared by many more users since the downlink antennas could be directional enough (like satellite dishes are) to reject other sources. This is true of geostationary orbit satellites, but the locations can only really be varied along an arc over the equator. Aeronautical platforms can be moved in two dimensions (obviously they really are in 3 dimensions, but the antenna aiming will still simply be azimuth and elevation).

      2. Better geographical isolation. Because they're lower, their horizon area will be much, much smaller. This means their service areas can be more easily limited. This can be done with antenna geometry for geostationary orbit satellites, but in general they can still see almost an entire hemisphere of the earth, so they can still raise the noise floor in otherwise out-of-service areas.

      3. Less delay. Geostationary orbits are far enough away that they introduce a delay that is unacceptable for most duplex applications (such as telephone or Internet traffic). Aeronautical platforms would be close enough to the ground that that delay would likely not be a factor.

      4. More servicable. The cost of launching geostationary payloads means that the payloads must be designed for a long service life, which raises the cost of the payload significantly, as well as the risks. Aeronautical platforms simply have to come down for a landing, be serviced, and then take off and fly back to station.

      5. Less chance of solar outages. Twice a year, there are a few days in a row where geostationary satellites transit the sun. Often, their signal gets drowned out when that happens. Aeronautical platforms stationed outside of the tropics, the problem can be avoided pretty easily (simply place the station to the north of the service area for the Northern hemisphere or to the south of the service area for the Southern hemisphere).

  4. Still a few bugs in this by sehlat · · Score: 3, Funny

    TFOT recently covered several other ground braking projects developed by students from the faculty of aerospace engineering in the Technion.

    "ground braking"

    Obviously the return and land part of the project needs work.
  5. Re:Well that was fast by garcia · · Score: 2, Funny

    The website is already suspended. Another notch in the Slashdot gun.

    The server runs on solar power. Unfortunately it's cloudy and their reserve ran out w/all the Slashdot traffic.

  6. excellent by Lord+Ender · · Score: 2, Insightful

    A hydrogen-filled blimp with docks for solar-powered planes could allow me to reign over those fools on the surface almost indefinitely!

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  7. Hurray to the advanced societies! by mi · · Score: 2, Interesting

    Unmanned probes that can reach not just Beirut but Tehran, and stay up for days waiting for the target? It's a sure seller, and the rich uncle Sam will as always pay for the new toys.

    A modern "Western" society (including Israel) is too advanced socially and culturally to deal with the inconvenient people the old-fashioned way — through massive killings, destruction, and/or religious conversions (the latter being the mildest form).

    While undoubtedly a good thing, this inability is seen by some as dangerous (sometimes even fatal) weakness — the underdeveloped enemy usually has no such self-imposed limitations.

    This article, however, reminds of the flip-side of the advanced society — the mind-boggling speed of technological and scientific progress, which will allow us to prevail without the above-mentioned ugliness. Israel, for example, will not need to "pull a Darfur", where hundreds of thousands of people were killed and raped, and millions driven out from their homes by the Arabs hordes unleashed by the government to suppress some insurrection or another...

    Instead, Israel will be able to use these machines to target the real enemies, keeping the innocents alive, even if enraged.

    Progress in weapons is a good thing — better weapons kill fewer people.

    --
    In Soviet Washington the swamp drains you.