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Space Science

NASA Flies First Laser-powered Aircraft 283

unassimilatible writes "NASA has successfully tested a small-scale aircraft that flies solely by means of propulsive power delivered by an invisible, ground-based laser. How far away can in-flight IP/LASER broadband be?"
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NASA Flies First Laser-powered Aircraft

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  • Laser (Score:3, Funny)

    by Colbens ( 238305 ) on Friday October 10, 2003 @09:00AM (#7181969) Homepage
    How far off can space death rays be is the real question
  • by Recoil_42 ( 665710 ) on Friday October 10, 2003 @09:05AM (#7182002) Homepage Journal
    or something like it:

    It used microwaves [friendsofcrc.ca] instead of "invisible lasers" (IR? i havent RTFA yet) but same end result, no?
  • Life Imitating Art? (Score:5, Interesting)

    by rit ( 64731 ) <bwmcadams&gmail,com> on Friday October 10, 2003 @09:06AM (#7182006) Homepage
    One of the hallmarks of classic science fiction, Larry Niven & Jerry Pournelles' "The Mote In Gods Eye" [amazon.com], proposes this very thing. The opening sections of the book are based upon on premise: lacking true FTL travel, an alien race reaches a human colony by building humungous lasers in their asteroid belt and planet surface, and using them to propel a light sail armed interstellar craft between stars. Good book all around, and it's cool to see decent Science Fiction become more than just speculative drivel (it's one of my favourite books).
    • No, that's a laser-augmented solar sail. Operating something like this in an atmosphere and a gravity well is a different animal entirely.
    • by orthogonal ( 588627 ) on Friday October 10, 2003 @09:24AM (#7182151) Journal
      building humungous lasers in their asteroid belt and planet surface, and using them to propel a light sail armed interstellar craft between stars.

      IANAP (I am not a physicist), but isn't using light pressure in a vacuum to drive a light sail entirely different from an aircraft with "specially designed photovoltaic cells carried onboard to power the plane's propeller"?

      It's like (poor analogy alert) saying that a gasoline powered car and a squeeze-jet that squirts out liquid gasoline to propel itself through the water are using "the same" propulsive technology.

      BTW, light sails were proposed by real physicists long before Niven and Pournelle wrote the excellent Mote in God's Eye.
    • Egdar Rice Burrows powered aircraft with the 8th Barsoomian Ray in the John Carter of Mars series.

      Basically the craft had a tank filled with light that propelled the vehicle around. ...And Tars Tarkas kicks ass too. =]
    • One of the hallmarks of classic science fiction

      Not "hallmark", "landmark".
    • Niven & Pournelle's Footfall [amazon.com] is a closer match. Aliens invade Earth and during the occupation, use ground-to-orbit shuttles that are partially launched by ground-based lasers. The lasers push the shuttle to an altitude where it's "safe" to crank up the main engine. Some resistance fighters manage to damage one laser ground-station during a launch, causing the loss of the shuttle, but they're subsequently creamed by the mothership. I don't remember if the shuttles glide to land, or come down ass-fir
    • I think that the "Angel's Pencil" (one of the first ships to encounter Kzinti) used a laser-based travel mechanism. Similar idea, but instead of the ship being fired into space by a big frickin' laser, it had one mounted which it used to bounce off various things for propulsion?

      In latter books, it mentioned using lasers to propel cargo/cargo-ships around.

      And the bonus is, of course, that when we are attacked by a carnivorous intelligent giant cat-species, we can use the lasers to fight back...
      • when we are attacked by a carnivorous intelligent giant cat-species, we can use the lasers to fight back

        Definitely. We'll also need big balls of string to distract them once they get bored chasing the laser beam spots around.

        Talking about giant cats reminds me of one of my favorite aphorisms about cats and dogs: If your dog was your size, he'd be your best friend but if your cat was your size, he'd try to eat you.

      • And the bonus is, of course, that when we are attacked by a carnivorous intelligent giant cat-species, we can use the lasers to fight back..

        When the Kzin first encountered humans, the Kzinti telepath assured his commander (Chuft-Captain?) that the humans had no weapons, because that was what he read in the humans' minds. He also opined that human might be tasty (even though given that the telepath wasn't a warrior, and so was despised, he'd never taste any).

        So the Kzin arrogantly attacked head on with li
  • Solar sails in space next?
  • Space Elevator (Score:5, Insightful)

    by cflorio ( 604840 ) on Friday October 10, 2003 @09:06AM (#7182010) Homepage
    This is the technology they want to use to power the space elevator.
  • by LorneReams ( 597769 ) on Friday October 10, 2003 @09:07AM (#7182014)
    If they are using laser beams to power a generator in the plane, why don't they use this to solve our energy distribution problem? In blackouts, just beam power to cities by laser.
    • If they are using laser beams to power a generator in the plane, why don't they use this to solve our energy distribution problem? In blackouts, just beam power to cities by laser.

      Got any spare gigawatt lasers lying around that you're not using to etch your name into the moon's surface? That's one hell of a power requirement!
    • The cost alone would be prohibitive to use this in municipal power stations. For now.
    • If they are using laser beams to power a generator in the plane, why don't they use this to solve our energy distribution problem? In blackouts, just beam power to cities by laser.

      Or cities could just use that big natural free radiation source called the Sun.
      • The sun only has an intensity of about 1KW/m^2m, whereas lasers are up at ~100MW/m^2.

        Also, solar panels are only about 5-15% efficient. That's because they only absorb certain frequencies of light, and the other frequencies that the Sun presents is wasted.

        However, if you point a laser at one, they're much, much more efficient (>50%). That's because you can choose the laser to match the solar panel.

        But the big problem with laser power beaming is stuff like clouds, and fog...

        • whereas lasers are up at ~100MW/m^2.
          But the big problem with laser power beaming is stuff like clouds, and fog...

          , people...

          • But the big problem with laser power beaming is stuff like clouds, and fog...

            , people...

            Nah, people are no problem. Cuts through them like a hot knife through butter. No problem at all. :-)

            Actually you wouldn't want to be within a mile or two of a 100MW laser. It blinds just from diffusively scattered light at about that range- further than that if you use magnifying optics like binoculars.

    • Two reasons.

      1. It is very inefficient.

      2. There is nowhere to beam it from. You need line of sight.
  • Hmm... (Score:3, Insightful)

    by MaestroSartori ( 146297 ) on Friday October 10, 2003 @09:09AM (#7182035) Homepage
    How far away can in-flight IP/LASER broadband be?
    I dunno, about as far away as in-car IP/gasoline broadband is? The craft in question is powered by laser, not using it to communicate with anything!
  • do you fly above clouds...

    :-)

    I live in England :-)

    • That's not the intention at all, at least for now. They are just demonstrating a technology and debugging it. Usefull applications are just speculation at this point, and don't have to involve that kind of altitude. For example, instead of erecting an atenna or camera tower, one could put them in orbit around an equipent truck at just a hundred feet altitude. How well this compares with just hanging the stuff from a tethered balloon, I'm not sure.

      Any technology distinguishable from magic is not suffic
    • Well... At least over at Claude Bernard, Lyon 1 University in France, they have demonstrated a data carrier laser system which can penetrate clouds and fog. I imagine som ecomercial application of that would be useful here.
  • by YouHaveSnail ( 202852 ) on Friday October 10, 2003 @09:19AM (#7182113)
    How far away can in-flight IP/LASER broadband be?

    Let's hope it's very, very far off. A laser beam pointing to/from a commercial aircraft is essentially a giant pointer, constantly updated, announcing the precise position of the plane. It should not be difficult at all to build a guidance system that follows the laser and delivers a payload to the plane just as a line climber [intothewind.com] follows a kite string to a kite. Said payload is not likely to be an emergency delivery of peanuts and soda.
    • It's Called Radar (Score:3, Insightful)

      by Myriad ( 89793 )
      A laser beam pointing to/from a commercial aircraft is essentially a giant pointer, constantly updated, announcing the precise position of the plane. It should not be difficult at all to build a guidance system that follows the laser and delivers a payload to the plane just as a line climber [intothewind.com] follows a kite string to a kite.

      Hmmm, a system capable of tracking the precise position of an aircraft? You mean like RADAR?

      Blockwars [blockwars.com]: free, and multiplayer

    • It's a backwards Smart Bomb!

      In Soviet Russia, ground smart-bombs plane!
    • I think you're talking FUD. We already have laser guided bombs/missiles, we've used them in the past 2 'conflicts' we've engaged in. Plus, this thing is invisible, so it's not like we're taking a visible beam of light to it. Adding a signal to the laser beam should be trivial...fast switching on and off to represent data.

      --trb
  • They directed a laser beam at photaic cells? Nice other name than solar panel. OK, the laser powered plain flies as long a laser hits it. But still the plain is carrying it fuel (photaic cell aka solar panel) on board, as meantion in the introduction. This is no breakthrough but rather a toy for big children.
  • Cool! (Score:5, Funny)

    by Garion911 ( 10618 ) on Friday October 10, 2003 @09:26AM (#7182164) Homepage
    I can see it now:

    "Homeless celebrate as pre-cooked pigeons fall from sky near airport"
  • by rf0 ( 159958 ) <rghf@fsck.me.uk> on Friday October 10, 2003 @09:26AM (#7182165) Homepage
    Well least missles won't need their own guidance now . They can just follow the laser.

    Rus
  • My only question is, how soon before Thinkgeek.com [thinkgeek.com] gets these? :)
  • by Moderation abuser ( 184013 ) on Friday October 10, 2003 @09:30AM (#7182200)
    The atmosphere is an ocean, you can float on it effortlessly. Why spend so much time trying to expend energy to stay up?

  • How does it work? And why do we want this? It's not exactly energy efficient or simple, is it?
    • One of the major problems with moving anything from place to place is getting energy to move it. That energy typically comes from partial conversion of matter (liquid oxygen, gasoline, coal, hay, etc.), and that matter in turn tends to be carried along with whatever you're moving. That matter in turn needs energy to move it, and in some cases this amounts to a rather offensive amount of overhead (e.g., Saturn V).

      There are two ways of handling this. One is to get the most efficient conversion possible, t
  • by hey ( 83763 )
    This is cool but I like China's space program better...they are going to be doing manned exploration of S P A C E.
    • Re:China (Score:4, Insightful)

      by Knobby ( 71829 ) on Friday October 10, 2003 @09:55AM (#7182397)

      This is cool but I like China's space program better...they are going to be doing manned exploration of S P A C E.

      National Aeronautics and Space Administration

      • Re:China (Score:3, Funny)

        by Dutchmaan ( 442553 )

        National Aeronautics and Space Administration

        If they just explored space they'd be the NSA... OH HEY! I think I've stumpled onto something!

        I'll be right back.. I hear a knock at the door.

  • A Few Comments (Score:4, Informative)

    by ChuckDivine ( 221595 ) * <charles.j.divine@gmail.com> on Friday October 10, 2003 @09:46AM (#7182323) Homepage

    I first read about this sort of thing back in the 1970s. Proposals back then focused on constructing huge satellites (think 5 miles by 5 miles or 10 KM by 10 KM) in geosynchronous orbit. Energy would be beamed to earth via microwaves or lasers.

    Planes could be powered via laser pointed at various reception devices (photovoltaic, steam generators, etc.).

    Clouds would not be a major problem. Just pick a frequency that penetrated the clouds fairly easily. Or, in the case of airplanes, fly above the clouds.

    For lots more information, just Google "Space Solar Power" [google.com].

  • What use is this? (Score:2, Insightful)

    by mactari ( 220786 )
    From the article:
    The plane, with its five-foot wingspan, weighs only 11 ounces and is constructed from balsa wood, carbon fiber tubing and is covered with Mylar film, a cellophane-like material.... The lightweight, low-speed plane was flown indoors at Marshall to prevent wind and weather from affecting the test flights.... Without the need for onboard fuel or batteries, such a plane could carry scientific or communication equipment, for instance, and stay in flight indefinitely.

    Okay, they've gotten a
  • by semanticgap ( 468158 ) on Friday October 10, 2003 @09:53AM (#7182371)

    It'd be nice if I could something like this to work to power my laptop!
  • You know, I have one simple request and that is to have aircrafts with freakin' laser beams attached to them!
  • How far away can in-flight IP/LASER broadband be?

    You know SCO will claim that it is their IP, and demand that all airline passengers must pay for a $699 license per engine ($1399 after next Wednesday).

  • by Eudial ( 590661 ) on Friday October 10, 2003 @10:18AM (#7182584)
    So, what happens when it gets cloudy?

    Or something else that vexes me even more greatly; will it be able to fly in london? (fog).
    • If the laser uses the right frequency, such as some forms of infrared, clouds will be transparent to it.

      I think this has it's best use in forms of helping a pilot who has run out of fuel. If planes move to fuel cell propulsion (There is a small fuel cell powered plane on the market now!) in the future, as they will once the technology is perfected in cars, if a pilot is running low on power, he can request a laser assist to limp to the nearest airport.
  • There is another laser powered craft that is much simpler. In fact, it has no moving parts. It looks like a fancy chrome plated frisbee, and is about that size. They get it spinning fast on the ground and then start shooting a laser at it from below. The disk is shaped such that the laser is reflected and a small chamber is heated, causing the air inside to expand, pushing air through a nozzle. The spinning gives it stability and the laser provides propulsion.

    I saw it on a PBS show about advanced propulsion devices a few years ago. Very much a research project, and not currently capable of carrying a payload, but interesting for its simplicity (in the craft at least).

  • I came up with this idea as a rocket propulsion many years ago while pondering the best way to get a rocket up. Go to Huntsville, AL sometime and walk along the Saturn V that's laying down there, and keep in mind that most of the fuel is simply lifting other fuel. By the time you get to the end of it, and realize that the tiny capsule is the payload, you know there's gotta be a better way. Keeping the bulk of the propulsion system ground based would allow you to fly something little bigger than a capsule
  • by PhracturedBlue ( 224393 ) on Friday October 10, 2003 @10:24AM (#7182632)
    Here [space.com]is a different solution (from back in '99) using a conical mirror to focus a high-powered laser and ignite the air underneath it to generate propulsion. Perhaps not generally useful yet, but perhaps more generally applicable than charging solar-cells with a laser.
  • Lightcraft Technologies Inc. have been flying laser-powered craft since 1997 their heighest flight reached a 233ft in October 2000.

    Their technolnogy is rather different to nasa's photon-pushed leightweight design, instead they have a 1-kilo spinning-top that has a curved mirror on the bottom, which focuses very short laser pulses from the ground to heat the air under the spinning top to extreme temperatures, 'blasting' the top upwards.

    Sadly, their website (www.lightcrafttechnologies.com) was last updated
  • What would be the spread of a laser from a geo-sync solar sat?

    Better efficency from space based solar collection?

    What effects would a power laser beam have on surface stuff (people, computers, animals, plants, etc.)?

    What if we had huge, tethered balloons, up several miles as receivers for space based power production. Could you use lower power transfer beams, since you wouldn't have to go through the lower 5-10 miles of atmosphere? You'd then pipe the electricity down to ground based distribution station
  • From the begining:

    Ever since the dawn of powered flight, it has been necessary for all aircraft to carry onboard fuel - whether in the form of batteries, fuel, solar cells, or even a human "engine" - in order to stay aloft.

    But a team of researchers from NASA......is trying to change that

    But how does it work Bob:

    The laser tracks the aircraft in flight, directing its energy beam at specially designed photovoltaic cells carried onboard to power the plane's propeller.

    Now how do 'solar cells' count as

  • Will they be able to propel craft all the way across the oceans by using a relay/tag-team system consisting of sharks with fricking laser beams attached to their fricking heads?

  • The basic problem is the laser: lasers are inefficient. For nearly every laser currently available, 99.9% of the energy you use to pump the laser goes into heat; only a small fraction is converted to coherent light.

    Current laser designs are capable of delivering watts of power, at the cost of kilowatts of energy. A few watts, even a few hundred watts is barely enough to power the map light in a plane/space capsule/whatever, let alone make it fly.

    They got away with this by:
    (a) using incoherent light (a sp
  • While the article may be correct that this is the first time a plane has been powered by laser light, there was the SHARP project [friendsofcrc.ca] that flew a plane powered by a microwave beam. It was fitted with a special microwave receiver that converted the beam directly to DC current. This project was envisioned to be used for communication platforms too. I wonder which version would be more energy efficient?
  • ...space tourist onboard playing Doom X, "What the hell! I've got a frickin' LIGHTSPEED connection, and my ping times suck ass! I want my money back!"
  • Hmmm, laser powered plane with IP/Laser connection. Post a link to the flight on slashdot and watch them soar! :-D

    (Yeah, I know it doesn't really work that way.)
  • How far away can in-flight IP/LASER broadband be?

    Pretty damn far. I'm still waiting for a flying car [retrofuture.com].
  • (obligitory obvious prior art posting to prevent people from patenting this stuff) Isaac Asimov "I, Robot" .. a space-based power station near the sun that beams the solar energy back to earth. Major plot that the station is taken over by a "religious" robot.
  • You consider a DC-3 full of backup tapes "broadband" otherwise that was just a sad non sequiter. Broadband and power over laser are two different technologies and have very different hurdles to surmount before being practical. Progress in one area does not neccicarily cause progress in another. Kids, we're loosing touch with reality, there are things that don't revolve around broadband. (I think)
  • They made a ground laser powered prototype aircraft [nasa.gov] and tested it. There is no way this current one is the first laser powered aircraft.
  • I can't believe NASA is getting press over this. It is a solar powered model airplane that has its solar cell power output increased by shining a laser on it. I expect to see this sort of thing at a high school science fair; not flight tested at both Edwards and Marshall (so that the engineers at each location could get some free travel, no doubt). It looks to me as if someone needs their budgets cut. Keep this waste of tax dollars in mind next time NASA complains that unless they get more money then th

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