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Battery-Powered Plane Taxis, Set To Fly Soon 179

Posted by timothy from the memory-effect dept.
bigdaddy writes "'WORCESTER - At 10:01 a.m. yesterday, Cary Dillman fastened her shoulder belts in the pilot's seat of a sleek twin-seat airplane, closed the cockpit canopy, and taxied into aviation history sounding - in her words - "like a sewing machine." Dillman was piloting the first conventional airplane powered by electricity.' How cool is that! Full details in this story."
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Battery-Powered Plane Taxis, Set To Fly Soon More

Battery-Powered Plane Taxis, Set To Fly Soon

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  • The article says that the plane is non-polluting - something I hear often of electric-driven things. Is there any quantitative measure of how much lesser pollution results from the electricity generation itself?

    • not to mention... (Score:3, Informative)

      by Trepidity ( 597 )
      ...the batteries, which often have lots of nasty toxic compounds in them (though that's gotten a bit better recently).

    • Re:non polluting (Score:5, Insightful)

      by Ismilar ( 222791 ) on Saturday September 14, 2002 @02:15PM (#4257346) Homepage
      No, because it depends where the power is generated.
      If it's here where I am, most (if not all) of my electricity comes from hydro and nuclear. If it's in the US, it'll likely be fossil fuels, but since it's produced in large quantities it will be less fossil fuels than what the plane would produce...

      So it isn't completely 'non polluting', but it's still much better than a regular plane.

      • Re:non polluting (Score:1, Informative)

        by Anonymous Coward
        Additionally, generation facilities can install multi-$$$ scrubbing / cleaning technologies on their stacks to prevent Nasty Stuff from getting into the air.

        A jet engine, as far as I know, just burns the stuff and has no controls in place for some of the nastier chemicals that result.

      • Those of us down here in hillbilly land are sold power by the Tennessee Valley Authority, from electric dams.

        Don't worry, I was born up north.
      • One big power plant is better than thousands of small power plants.
      • The idea is that electrical power is clean in principle, because it can be generated from renewable and non-polluting sources. If everything requiring energy could be efficiently powered with electricity, we would be a long way towards ending the use of fossil fuels.
    • Electric-powered vehicles usually pollute less because of the puny storage capacities of current battery technology. Since a battery can only store 1 or 2 orders of magnitude less energy per pound than a hydrocarbon fuel, this forces the vehicle designer to push for extreme efficiency in the vehicle to get any useful range at all.

      The electric power may or may not pollute less per joule than the energy from a conventional engine, but since so many fewer joules are being used, pollution is lower.

      If a better battery were to arrive that allowed you to get 300 miles range between charges driving a Lincoln Navigator at 80 MPH, you probably wouldn't be saving too much on overall pollution (at least with today's electric power generating mix).

      • "If a better battery were to arrive that allowed you to get 300 miles range between charges driving a Lincoln Navigator at 80 MPH, you probably wouldn't be saving too much on overall pollution (at least with today's electric power generating mix)."

        So if you apply that logic, to save the world, we must:

        1. Be willing to drive a vehicle that is inconveniently small so as to allow current electric motor technology to even be feasable.
        and
        2. Be willing to get there slower.

        (Anyone done time studies on the economic impact of being late a percentage of the time?)
        and
        3. Be willing to maybe not be able to get there in the first place should the destination be a little too far between charges...

        I don't know. I like the idea of electric vehicles, but I think the econimics are not there yet.

  • As a private pilot, I saw the headline and became excited. But alas, when I actually READ the article, I learned that this fancy all-electric airplane has not actually FLOWN yet!

    Taxiing is hardly a proof of concept when the point of the vehicle is to FLY!

    I don't see how this could possibly represent a first in aviation history until the thing actually flies...
    • As someone who works in the aviation sector, I can tell you that aviation works in babysteps.

      You start the engine before you taxi.

      You slow taxi before you high-speed taxi.

      All these things begin to tell you how the aircraft will behave and handle, as well as it's structural integrity, without putting the pilot's life in immediate peril. Only when you're absolutely as sure as you can be that the whole thing wont fly to pieces around do you accelerate and rotate.

      Would YOU sit in an untested prototype plane and throw the throttle to the stops without having any idea what was going to happen? Any problem you might encounted at 0 feet AGL is a lot more serious at 1000 feet AGL.

      • Only when you're absolutely as sure as you can be that the whole thing wont fly to pieces around do you accelerate and rotate.

        And only then have you reached an aviation milestone. Until then, you've built an inefficient, funny looking car.

        Look at Eclipse. They've been doing all sorts of taxi tests, engine tests, and so on for months, even years. But only with the first flight have they silenced the naysayers.
        • I like to see this sort of competition in the aircraft industry. Why buy a Cessna Caravan turboprop for $1.4 million when you can get a 6-seat Eclipse jet for $850k?

          The Eclipse 500 is fuel-efficient, quiet, and inexpensive. Not to mention it has already flown! In short, it appears to be a superior aircraft (I have not personally seen one and have certainly not flown one).

          But it doesn't run on electricity, so it isn't sexy to the ecologists and it won't turn heads on /.

          But in my opinion the first flight of the Eclipse 500 is much more of an aviation milestone than the first taxi of a battery-powered plane that will have a 100-mile range.
          • I don't know about this one, but after you get to the airport, finish the preflight checks, taxied your way to the run way, and done all the landing procedures on the other end, you have to fly more than 100 miles to have any real time savings. With only a hundered mile range, your will arrive faster driving to your destination. Battery technology is not good enough to match cars, which do not have to operate with anywhere near the same power to weight ratio as planes.
            Making an exclipse prototype fly is easy, they spent quite a bit more than a production model, making planes that actually sell for 850k will be an amazing achievement in aviation. Even so, it is still much more significant than this electric jet.
      • Would YOU sit in an untested prototype plane and throw the throttle to the stops without having any idea what was going to happen?

        Why not make the first prototype remote-controlled? (with the control circuitry being on separate batteries than engine power)

        • Making a prototype vehicle remote controlled isnt as easy as sticking a futaba R/C radio set in it like it's a model.

          Making a real full-size vehicle remote-controlled requires firstly a communications link capable of streaming all your commands, plus returning everything you want to know about how the aircraft is responding. And you have to do this over long ranges. and unless you are the military, you have to do this within FCC civilian broadcast guidelines.

          It's not easy to do, and it's much cheaper to simply do it like it's been done for almost a century, with a human test pilot behaving very cautiously.

          A human is the I/O, the sensors, the actuators, the flight control processor, and everything else.
          Automating a small plane would most likely double the cost, at least.
    • Sorry, but the headline never actually said that the plane flew-- it taxied, but it was 'set to fly soon'.

      In other words, the headline indicated that it had not flown yet. This was pretty obvious, I believe.

      • Yes, and looking back, I should not have gotten excited about it in the first place.

        All I meant to imply is that a TRUE aviation milestone requires flight. Not taxiing.

        Obviously taxiing must come first, but how interesting is it? Show me that this plane will fly (which is the question), and then it becomes very exciting news.

  • Fuel Cell Plans as Well (Score:4, Informative)

    by pgrote ( 68235 ) on Saturday September 14, 2002 @02:17PM (#4257352) Homepage
    Dunn is also working on Fuel Cell planes.

    Fuel Cell and Aviation [aviationnow.com]

    He says, "There is a limitless supply of hydrogen, and it poses no environmental harm, unlike carbon dioxide and other compounds generated by traditional gasoline or diesel engines," Dunn said. "
  • I went to WPI and living in Worcester has taught me that it's only a matter of time till someone steals the plane and sells it to a chop shop.
  • So, all we need to do is combine this plane with the tilley foundation's amazing electric engine and then people can fly forever. Oh wait, that's assuming the tilley foundation isn't a complete hoax :)
    • FYI, the Tilley's said they would actually bring an airplane with them for their next test-run in about 30 days.

      I don't think anything about the Tilley device yet, until it is definately proved to be either a hoax or a blessing. I must say though, that if Tilley is a fraud and not just self-disillusioned, he's also incredibly stupid, because we all know what will happen to frauds in our time.

      Anyone has any good suggestion what we should do with him?
      • It would be nice if the tilley thing turns out not to be a fraud, but thermodynamics seems to suggest it is. If this Tilley device works as it seems to claim, then I could hook up the crankshaft of the car to turn a generator. In essence I could create energy out of seemingly thin air. I'm looking forward to either their revelation as a fraud or a detailed explanation of how the physics of this thing actually works.
  • until petrocorps buy the patent? Lets start the countdown
  • An airplane with 100 mile range, goes great with your car's 100 mile range, and your tax-payer paid for Ginger's 18 mile range.

    Fortunately I doubt the public will get soaked for this ludicrous attempt. We already get soaked with special tax breaks and such for electric cars and its obvious Segways were only developed to be sold to Government. (who else would blow 8k on something with so little use except to haul overweight bureaucrats around?)

    Batteries are a dead-end option for helping the environment. Far better to call them coal-fired future environmnetal hazards!

    Amazing, we had a 100 mile range car in the late 20s or early 30s, are we just that stupid to keep going this route?
    • Amazing, we had a 100 mile range car in the late 20s or early 30s, are we just that stupid to keep going this route?


      Hear, hear! Egg Troll dislikes the limited range of electric vehicles. Its well known that the biggest inconvenience in driving today is the limited range of petroleum-based automobiles. Thus Egg Troll supports government-funded research on a nuclear-powered car. Imagine being able to drive for several years without having to stop for gas!

      Its the way of the future!

    • Everything he just wrote was absolutely true. Until they make batteries that are practical for more than running a remote control or power tools all these engineering studies are a waste of time and resources. If you want to make electric powered vehicles, then you need to put more funding into energy storage. Flywheel technology is a better storage medium than a battery and doesn't need the toxic chemical that a battery does. Chrysler has toyed with the concept for a while now but didn't go on to overcome the technological hurdles of the technology. Fuel cells, as stated many times in this thread, have vastly better potential than any other technology out there for powering personal vehicles. The powerplant is now small enough to be practical. Now they just need to work out fuel storage or conversion to bring it to market.
    • A Cessna 172R specs claim a range of 580 NM. 100 NM's not that bad. Fuel cells will greatly extend the range and make it practical and that's the technology they're really targetting, as the article points out.
    • It is an excellent start on fixing a problem that is could stop general avaition in is tracks. 100LL fuel (most piston airplanes use this fuel) will be outlawed for use by the EPA in the not too distant future. There are only two alternatives; diesel and electric. Diesel has quite a head start but it still uses fossil fuels burned in the aircraft. Congrats to this group in trying to come up with an alternative. I look forward to my first chance to fly an electric airplane
      • 100LL fuel (most piston airplanes use this fuel) will be outlawed for use by the EPA in the not too distant future. There are only two alternatives; diesel and electric.

        And automotive gasoline. The vast majority of piston aircraft engines will burn automotive gas just fine, and many of them already do.

  • I can just picture the faces of all the rich people who run out to buy one of these when they get it home and read the small print:

    Batteries not included
  • What will hailing these cabs in New York be like?
  • ..are less physcotic that normal [sic] NYC cabbies.
    Last time I took a cab my driver winged through central park at a ludicrous speed nearly maiming a couple courageous joggers. I've never seen a hotdog vendor move so nimbly.

  • Cary Dillman (Score:3, Interesting)

    by Perdo ( 151843 ) on Saturday September 14, 2002 @02:45PM (#4257454) Homepage Journal
    Is a member of the Worcester Area Pilots Association [worcesterapa.org].

    Nice little slashcode site.

    Definite honorary member of the cool geek society.
  • The goal [is] to create a plane that might be simple to build and maintain, would be reliable, would produce no emissions, and would be inherently quiet.

    In other words, recreate the blimp.
  • Personally, I wouldn't mind driving an electric car, but I'd be somewhat reticent to get aboard an electric plane "beta." If the batteries for some reason die or don't quite last as long as expected, I'd much rather have my car power down along the side of the highway, than have my plane suddenly choke up in midair.

    The first few tests will take a lot of courage. Bravo to those that participate. Chances are we won't be seeing electric-powered helicopters until long afterwards however... they tend to resemble rocks when the power gives out to the rotors.

  • Won't be that quiet. (Score:4, Insightful)

    by Gordonjcp ( 186804 ) on Saturday September 14, 2002 @02:50PM (#4257473) Homepage
    You can have a very well silenced piston engine aircraft, but most of the noise comes from the propeller. The Chevvron 2-32C [hiway.co.uk] sounds like an electric strimmer two gardens away, with its 32hp two-stroke engine. At full throttle, all you can hear is a faint buzz from the engine, and quite a bit of noise off the prop.
  • because God help you if your batteries go dead at 3000 feet. Personally I'd rather be in a conventional aircraft. That way (assuming there's more than one engine) a malfunction doesnt automatically mean I'm going to crater
    • Are you joking?

      Batteries, much like a fuel tank, drain. And it's just as easy to rip a hole in the tank or feed tubes as to disrupt the electronics going to a battery of batteries.

      Compare the mechanical complexity of electric and combustion motors. I would expect an electric plane to be much more mechanically reliable than a internal combustion or jet engine aircraft.

      BTW, unpowered landings in these small and slow airplanes are actually pretty safe, it's mostly depends on ability to find appropriate terrain.
    • You saying that a heavy combustion engine that's also dead, is better than a lighter electric engine? I've never seen any extra fueldunks in any of my flights, and even if I did, I sure wouldn't want to climb out on the wing to refuel it at 3000'.

      With an electrical/hydrogen plane if the electricity run out, you just use your walkman batteries and fly home...
  • I remember back in 91 or 92 landing at Virginia Tech, and as I taxied in the little 152, there was a crowd gathered and pointing. Apparently they weren't in awe of my piloting skills; they were actually pointing behind me at what looked like a small sailplane landing.

    The wings were covered in solar collectors and the small cockpit had two instruments in the panel, a handheld radio, a flimsy plastic seat, and a rack of batteries. They said it could take off on its own power. This sounds a lot more non-polluting than plugging a stack of batteries into the wall (although I'd assume they probably pre-charged the plane beforehand).

    I can't find a link as my searches all point to things that look more like stick-and-cloth ultralights. This one was a sleek little fiberglass plane.
    • Wallah [lange-flugzeugbau.de]. The word you're looking for is "electric motorglider". There are several flavors available, and it's a really really cool idea. The solar panels don't provide enough power to continually run the motor, but they can supplement the batteries under powered flight and recharge them when in gliding flight. Some motorgliders have retractable propellers to improve performance while gliding.

      In other words, it's a super-cool way to fly.
  • "Oh my god! The battery is DEAD! Alright now, WHO left the headlight on?!"
  • Okay, so this is newsworthy? They say that it hasn't flown yet, and will only fly for an hour when it does get going. Additionally, then mention that electric planes have already been made that have flown over the English Chanel, and such.

    So... What is so exciting? It's like saying:

    "Look I've got the first T.V.... No it's not the very first one, but it's the first working one with square-shaped knobs! And by the way, we don't know that it works yet."
    • I assume you'd be similarly cynical about the Wright Brothers. Their first day of flying yeilded speeds slower than a bicycle and a distance of less than 100 yards, yet it proved that the technology was feasable.

      The way I see it, students and volunteers working on a low-budget proof of concept would probably see at least half an order of magnatude improvement when working with refined tools, a plane specifically built around the flight tolerances expected, more heavily researched and mass-produced.

      True, it would be nice if it got off the ground, but the forecasted specs for this prototype, 100mph and 100mi range, don't bother me in the least.
      • The Wright Brothers proved that powered flight was possible... This announcement admits that this is not new, it's more or less just the first time that THEY have done it (and they haven't even really done it yet). Just another press release that inexplicably gets a front-page spot on /..
  • Wow, it would be so cool to hail one of these taxis! "Hey driver, take me to the roof!" It's gonna be a "Blade Runner" future, for sure. Battery powered Flying taxis, who da thunk it?
  • What happens to the motor in the event of lightning strike? A gas engine will not lose power after a lightning strike, but an electric engine would probably be fried.

    • if you get hit by a bolt of lightning in a composite airplane you would have problems anyway. in a metal airplane the lighting would pass right through you, gas of electic you wouldn't be grounded so no big deal.
      the real killer with lightning strikes is the heat generated by the 1.21 gigawatts.
      In a fiberglass and foam airframe it's the big hole in the wing that kills you.
      Not lossing your engine.

      I think a few years ago Lancair solved this by putting a clear matalic coating on the plane, it was sposed to help if not solve the problem.
  • That's going to be one LONG extension cord.

  • Been flying battery powered planes for years ... (Score:4, Informative)

    by dougmc ( 70836 ) <dougmc+slashdot@frenzied.us> on Saturday September 14, 2002 @03:29PM (#4257622) Homepage
    Electric R/C planes have been quite popular for several years now -- in fact, it wouldn't surprise me at all if people were drawing on the experience gained there to design/improve this plane.

    They tend to suffer from the same problems, however -- low flight times. You can have an electric R/C plane that's extremely high performance and fly for 3 minutes (with Ni-cads), or a very very tame flying plane that flys for 30 minutes (using Li-ion cells.) With a glow or gas engine, you can have a very high performance plane that flies for 30 minutes -- or you can try and fly across the Atlantic in an 11 lb plane [dc-rc.org].

    Electrics are quieter, cleaner (no oil sprayed everywhere) and easier to deal with, which are the main reasons for their popularity. You can fly them where gas/glow planes would not be allowed.

    Still, a plane that carries a passenger (i.e. not a model) for only 100 miles per charge really isn't going to be that useful. They're going to need to be able to make the fuel cells work before this plane will be accepted as anymore more than a toy. Either that, or they're going to need to make a *massive* improvent in battery technology -- such as being able to hold 5x as much charge. It may happen eventually, but it's not likely to happen soon.

  • Novelty value (Score:4, Insightful)

    by Patrick ( 530 ) on Saturday September 14, 2002 @03:48PM (#4257675)
    Dunn, giddy over the success of the exercise, responded: ''This is the future of flight.''

    That's unlikely. Batteries weigh far too much for the amount of energy they can store. Jet fuel is hard to beat from an energy density standpoint. Weight matters a lot on an airplane.

    A practical electric car would be much more useful. Cars spend more time idling, have less efficient engines, and do all their polluting in a relatively small space. Airplanes, in contrast, fly efficiently, generate thrust efficiently, and spread out their pollution better. There's a lot less need for electric planes, even if the weight and refueling problems could be solved.

    At least he didn't suggest hybrid planes that employ regenerative, um... braking.

    One last question: why did the electric motor cost $20,000?

    • $20,000?

      Go check your junk box, see if you have an electric motor that is light, and at the same time powerful enough to tow an airplane without burning up.
  • As a generalized reply to people who have been saying "what if the batteries die," you need to realize that the batteries would have a very predictable rate of degeneration. To say gasoline engines (or jet fuel, whatever) makes you more comfortable is foolish. It's just as possible to run out of gas as it is battery power; all you have to do is start ignoring the instruments.
  • Follow the reasoning carefully, now...

    Well, they plan on powering a future version with a fuel cell, right? Those require hydrogen. Hydrogen is lighter than air, right? Well, if they fill the plane with enough hydrogen, who needs wings? It can just float into the sky! And to power it, it can still just burn the hydrogen!

    Oh, damn. Never mind.
  • After seeing the headline, I thought that I was going to get to read about how I can hail a cab when I need to go somewhere, only now I'll have the choice between a big yellow car and a cool electric plane. The reality is far less pleasing.
  • I thought this was going to be about planes serving as taxis! What a gyp.
  • I can't wait to hear, "This is your captain speaking. Please fasten your seatbelts and put your head between your knees. I'm going to change the batteries now."
  • "How cool is that!"

    Not really that cool. If you compare it to things like having groupsex with two gorgeous blondes. Or even having sex, actually.

  • Batteries can't beat combustion (Score:5, Insightful)

    by mc6809e ( 214243 ) on Saturday September 14, 2002 @04:41PM (#4257872)
    Energy Density of Some Materials (Wh/kg)
    Hydrogen ---------------> 38,000
    Gasoline ---------------> 14,000
    Compressed Air ---------> 2,000 / m^3
    Flywheel, Fused Silica -> 900
    Hydrostorage -----------> 300 / m^3
    Flywheel, Carbon Fiber -> 200
    Zinc, Al Air Batteries -> 200
    Lithium Iron Batteries -> 150
    Nicad Batteries --------> 55
    Flywheel, Steel --------> 50
    Lead Acid Batteries ----> 40
    Batteries just can't compete on weight with other sources of energy. Looking at the above table, we see that the best batteries (Zinc Air with sacrificial anode) provide just 1/70th the energy kg for kg that gasoline provides. Electric vehicles seem to be a dead-end to me. A lot of energy is spent just moving the batteries themselves from place to place. The physics are strongly against battery-powered vehicles.

    A much better approach would be to determine how we can produce gasoline from CO2 and H2O or coal, using some other source of energy to get the job done. It's already possible to produce natural gas this way.

    • Gasoline combusts, producing heat, which is (among other reasons) why we cool engines.

      Unless you're having way too much fun, batteries do not combust, and produce very little heat.

      It's not just about energy content, it's about how you translate that energy into motion.

      Hmm:
      Anyone up for an internal combustion/steam powered hybrid plane?
  • The U.S. military is already making use of unmanned spy planes to get a view of the other side of a battlefield before committing troops. However, these are not supersonic planes so they can be heard before they are seen. There is a lot to be said for the concept of a short/medium range unmanned aircraft that makes almost no sound until it is on top of you, and has a very small radar signature (if it even flies high enough to be seen). When you don't have to carry 200 lbs of pilot and the extra weight of the plane needed to safely carry that pilot you can extend the range quite a bit. 200 miles round trip would be very doable and very useful. The whole aircraft could fit in the bed of a pickup truck and be assembled and ready to fly in minutes. Total cost of the aircraft could be a fraction of what manned aircraft cost. Maintenance would be much cheaper. They could be refeuled cleanly in the field, without the need to ship feul in (attractive target for NME!). The U.S. military has shown a heightened interest in unmanned and autonomous aircraft in recent years. I would not be in the least bit surprised if the results of this experiment contribute greatly to the sorts of aircraft we use in battle ten to twenty years from now.
  • Airplanes are expensive to own and fly, and one of the main problems is the internal-combustion engines. Even a little Cessna 172 needs an engine overhaul every 2,000 hours or so, at a cost of US $15,000 or more each time. The engines on a six-seat twin can cost far over USD 50,000 to overhaul. Go online and look at how many used small planes for sale have a time since major overhaul (SMOH) of close to 2,000 hours -- the owners are forced to sell because they cannot afford an overhaul.

    Electric motors don't have cylinders that get scored, seals that leak, and so on. A lot of small plane owners like to go up for a quick spin on nice weekends, and it doesn't sound like the battery technology is too far off for them (2 hours would be fine for a sport plane) -- it might just make flying affordable.

    I agree that we're a long way off from a battery-powered 747, if such a thing were even worthwhile.
    • My little Piper Cherokee cost me $25K... about the same price as a new SUV or extended cab pickup truck. The engine was freshly overhauled when I bought it. If I fly about 100 hours a year, and nothing major breaks on the engine, then that 2000 hour TBO translates to 20 years. Lycoming suggests 2000 hours or 12 years on my O-320-E2A, whichever comes first. In actuality I fly more like 150-200 a year which means the engine has at least 10 years of useful service life but still, that $25K SUV or pickup truck will be worn out and worthless after 10-12 years of regular driving. The Piper will last forever, and will simply only need another engine overhaul then, and it will always retain it's resale value.
  • As far as the air frame goes its nothing new under the sun, looks like another KIS of Lancair knockoff. The Motor is simlar to the ones used in home EV converts. The real neat bit it the batterys, If I recall correctlly he said that a car battery would be about the size of a CD jewel case and weigh about 8-10 OZ. He was very nice and willing to explain every thing in great detail.
  • It's interesting that the article completely ignores Helios [nasa.gov], NASA's tested and proven high-altitude, entirely solar and battery-powered aircraft.

    It seems absurd to say that the only route to a viable ZEV passenger aircraft is to stuff batteries into a conventional aircraft, and try to make it more efficient. Conventional aircraft have evolved based on the assumption of a significant power source.

    Avenues of research involving the creation of ZEV aircraft, like Helios or a glider with a battery booster, that work well for their given tasks, are just as, if not more, viable ways to reach the destination of a viable ZEV commuter craft.

    Mandating novel energy sources but ignoring novel form factors seems pretty short sighted. I hope it's only the Globe article's author who pooh-poohed such avenues, and not the researchers in the field.
    • It's interesting that the article completely ignores Helios [nasa.gov], NASA's tested and proven high-altitude, entirely solar and battery-powered aircraft.

      A fantastic feat of engineering it may be, but you missed out the rather crucial word "unmanned"...

      Phillip.
      • "A fantastic feat of engineering it may be, but you missed out the rather crucial word "unmanned"..."

        Boy, it's a good thing those first rockets had people in 'em. Otherwise they'd have been worthless at getting us to be able to build rockets that could hold people.

  • History?! (Score:4, Insightful)

    by Ethanol ( 176321 ) on Saturday September 14, 2002 @07:48PM (#4258619)
    There've been electric-powered planes for at least 25 years. Paul MacCready's team, the same ones who built the first human-powered airplane in the 1970s, built a solar-powered (and thus, obviously, electric) airplane called the Gossamer Penguid.

    And six years ago, a team at the University of Stuttgart built this [uni-stuttgart.de], a fully solar-powered self-launching motorglider (that is, an airplane which is intended to shut off its engine and glide once it reaches altitude).
  • OK, lots of people have adequately made the point that taxi tests aren't interesting, and to be honest, this isn't a new airframe.

    To understand what's actually being worked on here, you'd have to do two things that exceed the ability of the average slashdotter...

    a) read the article
    b) think

    The article says that they're also working on Fuel Cell aircraft. Even the average /. reader will know that the output of a Fuel Cell is electricity.

    So here's the plan, such as I can infer from the press coverage:

    1. Take existing airframe
    2. Retrofit for electric power
    3. Prove electric power in flight tests from batteries ...and only after you have that working...
    4. Replace batteries with Fuel Cells

    Actually, if there's room in the weight budget, you could keep all or part of the batteries as emergency reserve. It would be pretty compelling to have 100NM of reserve in the event of a fuel cell failure, though the motor itself seems far more likely to fail.


    • Actually, if there's room in the weight budget, you could keep all or part of the batteries as emergency reserve. It would be pretty compelling to have 100NM of reserve in the event of a fuel cell failure, though the motor itself seems far more likely to fail.

      Umm, why? I'd say the fuel cell and it's support systems are much more likely to fail than the engine. While the article doesn't say, I don't think they used a DC engine with failure-prone brushes. A AC induction motor or a switched reluctance (SR) motor with assorted power semiconductors to control them is much more simpler, lightweight and efficient. Of course they could have used a permanent magnet motor too, but those are expensive as hell. Fuel cells, on the other hand, are a relatively unproven technology. There's lots of stuff there that could break. Maybe not the cell itself, but stuff like air compressors, fuel pumps etc.

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