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Power Transportation Businesses Technology

All-Electric 'Flying Car' Takes Its First Test Flight In Germany (theverge.com) 178

Today, Munich-based Lilium Aviation conducted the first test flight of its all-electric, two-seater, vertical take-off and landing (VTOL) prototype. "In a video provided by the Munich-based startup, the aircraft can be seen taking off vertically like a helicopter, and then accelerating into forward flight using wing-borne lift," reports The Verge. From the report: The craft is powered by 36 separate jet engines mounted on its 10-meter long wings via 12 movable flaps. At take-off, the flaps are pointed downwards to provide vertical lift. And once airborne, the flaps gradually tilt into a horizontal position, providing forward thrust. During the tests, the jet was piloted remotely, but its operators say their first manned flight is close-at-hand. And Lilium claims that its electric battery "consumes around 90 percent less energy than drone-style aircraft," enabling the aircraft to achieve a range of 300 kilometers (183 miles) with a maximum cruising speed of 300 kph (183 mph). "It's the same battery that you can find in any Tesla," Nathen told The Verge. "The concept is that we are lifting with our wings as soon as we progress into the air with velocity, which makes our airplane very efficient. Compared to other flights, we have extremely low power consumption." The plan is to eventually build a 5-passenger version of the jet.
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All-Electric 'Flying Car' Takes Its First Test Flight In Germany

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  • by Anonymous Coward

    More like a small aircraft with VTOL capabilities.

  • Electric, or Jet? (Score:3, Insightful)

    by Dawn Keyhotie ( 3145 ) on Friday April 21, 2017 @09:07PM (#54280625)
    Can't be both, unless it's a hybrid. I guess that's possible.

    /DNRTFA
    • by Anonymous Coward

      Whatchoo talking about? Electric ducted fan.

      • From the article: "The craft is powered by 36 separate jet engines..."
        • Lets everybody take a deep breath. I RTFA, no specification sheet? Also, and one has to swallow hard about this, what is the glide slope ratio?
          • what is the glide slope ratio?

            It looks to me like it would be less that 1/1. I wouldn't want to be in it when the motors failed.

    • I came to post the same thing. It is a plane. It is not a jet nor a "jet plane" because it has no jet engines. Jets create propulsion from burning gases. It is a multiple prop or ducted fan plane.

      • Wrong. Burning anything is not required for a jet engine and an electrical jet engine is perfectly possible, just not practical because the air in the engine core would have to be heated electrically to add pressure.

        • https://en.wikipedia.org/wiki/... [wikipedia.org]

          "A jet engine is a reaction engine discharging a fast-moving jet that genenerates thrust by jet propulsion. This broad definition includes airbreathing jet engines (turbojets, turbofans, ramjets, and pulse jets) and non-airbreathing jet engines (such as rocket engines). In general, jet engines are combustion engines. In common parlance, the term jet engine loosely refers to an internal combustion airbreathing jet engine."

          Not a word ANYWHERE on that or any related article in

          • This wikipedia definition contradicts itself. It calls a turbofan a jet engine but a modern turbofan generates thrust with the fan and the whole compressor-combustor-turbine setup is there to drive the fan. But like I said, an electrical jet engine is perfectly possible, and in many different ways. The stupidest version would be very much the same as a turbojet, only without fuel lines and the combustor replaced with electric heating. This is incidentally how a nuclear jet engine works, with the difference

          • by suutar ( 1860506 )

            Nor, anywhere in the actual definition (the first sentence) does it require combustion. "pushes fluid thataway fast" is all it's got, really.

    • Fan would be accurate.
  • by Tough Love ( 215404 ) on Friday April 21, 2017 @09:23PM (#54280709)

    This demo is just a hover demo, the wings are actually just pure decoration for promo purposes. Not to say that a hover demo is an easy feat, but the cool looking slippery fuselage is not doing anything useful in an aerodynamic sense, rather it is purely for social engineering at this point. Doubt me? Look at the canard, it is not even an airfoil by any stretch of the imagination. This aircraft is absolutely incapable of gliding, it would immediately dive straight down if you tried to do so, with spectacular results.

    Given that this is just a hover egg, maybe optimize it for that? The concept render actually shows an airframe that could be capable of some kind of glide ratio, but from the look of it, only at really high speed. Trying to flare out for a standard runway landing would most likely be a life threatening experience. With all those ducted fans, the profile drag will be through the roof. Glide ratio, maybe 5 to 1, optimistically, unless the profile drag can be reduced by some as-yet uninvented magic. By comparison, a garden variety Cessna gets 9:1, which means that landing without power already requires some skill. With 5 to 1, you basically need to be a Chuck Yeager to walk away from it.

    Might as well just be honest about it and lose the wings entirely. Simple sticks will do, like the canard, and save some weight. Then what is the remaining reason for having such small fans? Small fans are less efficient than larger ones, meaning the batteries will run out considerably faster than some more practical design.

    • You seem to know a lot more about aero-dynamics and flight than me (not saying much).

      But aren't you comparing this vehicle to a plane when perhaps it should be compared to a helicopter? In that case, would the lift from the airframe moving forward would be much more than an equivalent helicopter and thus the range would be much better?

      True, if the engines die you can't "glide" it back to a landing. However the massive redundancy (36 fans) would prevent that from being the point of failure (but the battery

      • Re:Wrong comparison? (Score:4, Interesting)

        by Tough Love ( 215404 ) on Friday April 21, 2017 @10:24PM (#54280939)

        aren't you comparing this vehicle to a plane when perhaps it should be compared to a helicopter?

        It a fuselage optimized for forward flight and it has wings. Therefore it is trying to appear to the view as a plane. It is really a helicopter, as you say, and as I implied by calling the show a "hover demo".

        In that case, would the lift from the airframe moving forward would be much more than an equivalent helicopter and thus the range would be much better?

        No, for several reasons. The lift from the the slippery egg shape will be roughly zero except at stupidly high angles of attack and stupidly high speeds, so forget that. The lift from the main, rear wing will be pathetic because of the massive disruption of flow causes by the ducted fan housings. And the wing loading is way too high anyway. The video optimistically implies some kind of laminar flow over the wing and through the fans, but the there is so much structural junk in that way that I will have to call that pure fantasy. That rear wing assembly has airfoil efficiency roughly equivelent to a backyard barbeque.

        And that is not the worst problem. Aerodynamically, the worst (of many) problems with this concept design is, the forward canard will generate exactly zero lift. All the lift at the front comes from the vertical thrusters, which will need to stay running (at high speed and power consumption no doubt) the entire time that the plane attempts to maintain efficient horizontal flight. This issue could be somewhat fixed by changing the forward ducted fan assembly into a real canard as in the concept animation, but with all the junk attached it would be a contender for world's least efficient canard wing, and fragile to boot.

        Obviously, unpowered gliding is a complete non-starter with this configuration. At best, some inefficient form of foil-assisted forward flight will be possible, most likely not efficient enough to justify the additional weight and wetted surface of the real airfoil.

        if the engines die you can't "glide" it back to a landing. However the massive redundancy (36 fans) would prevent that from being the point of failure (but the battery, power electronics might be)

        You might want to upgrade that "might" to a "will". Consider the case of flying over water with unexpected headwind that lengthens the trip past the battery endurance, or countless other scenarios that come up regularly in real life.

        That's where the parachutes come in I guess.

        I suggest, some healthy skepticism will come in even more handy in terms of minimizing loss of life.

        Since I'd rather have a (safe, easy to fly) helicopter than a plane, I think I'd buy this to go (short) island hopping in the South Pacific. :)

        You're a great straight man, you know that? Exactly the scenario I mentioned above...

        If you plastered it with solar cells, how long would do you think it take to charge?

        How much time have you got?

        • In that case, would the lift from the airframe moving forward would be much more than an equivalent helicopter and thus the range would be much better?

          ... This issue could be somewhat fixed by changing the forward ducted fan assembly into a real canard as in the concept animation, but with all the junk attached it would be a contender for world's least efficient canard wing, and fragile to boot.

          Just add plain airfoil canards on the outer ends of the forward nacelles and you will have an aircraft with fully functional canards.

          • In that case, would the lift from the airframe moving forward would be much more than an equivalent helicopter and thus the range would be much better?

            ... This issue could be somewhat fixed by changing the forward ducted fan assembly into a real canard as in the concept animation, but with all the junk attached it would be a contender for world's least efficient canard wing, and fragile to boot.

            Just add plain airfoil canards on the outer ends of the forward nacelles and you will have an aircraft with fully functional canards.

            Just add plain airfoil canards on the outer ends of the forward nacelles and you will have an aircraft with fully functional canards.

            But that is not what was demonstrated, and it will still fly like a brick without hugely increased foil area, including the rear foil. Do not underestimate the disruptive effect on lift of the turbulence around the motor housings. By the time the foils are large enough to glide safely or even significantly increase endurance, this design is back to being just a VTOL canard plane, not remotely in the ballpark of a flying car. Clearly the promoters are trying to pull one over on the public: this thing is real

  • by byteherder ( 722785 ) on Friday April 21, 2017 @09:30PM (#54280731)
    This flying car won't fit in my garage, won't travel down the highway (or any road for that matter), won't land at the grocery store and pick up milk.

    It only works if you live at an airport and your house backs up to the runway.
    • Flying "car," indeed. It's not even a "roadable plane" - I suspect it'll be a miracle if it even ends up being a "flyable plane."
    • This flying car won't fit in my garage, won't travel down the highway (or any road for that matter), won't land at the grocery store and pick up milk. It only works if you live at an airport and your house backs up to the runway.

      Unfortunately, this is going to be like an autonomous taxi. We probably won't be able to get one.

      • This flying car won't fit in my garage, won't travel down the highway (or any road for that matter), won't land at the grocery store and pick up milk.

        It only works if you live at an airport and your house backs up to the runway.

        Unfortunately, this is going to be like an autonomous taxi. We probably won't be able to get one.

        I've come to the conclusion, finally, that few-passenger air transport like this or flying cars must be entirely computer-controlled. Humans are idiots. Plus, the extra weight of a steering console would eat into range. GPS-based point-to-point, with landing pads sprinkled throughout a city, is the only sane way to go. And it's looking more viable with this aircraft.

        • Humans are idiots.

          I'm trying to imagine the texting based accidents. Things happen so much more quickly at flying speeds.

    • by krigat ( 1253674 )

      It only works if you live at an airport and your house backs up to the runway.

      Why is that? It can start and land vertically, so you don't need a runway. You just need some "parking space" in your garden. Judging from the scene where that guy is lying under the wing, the total wingspan is around 10 meters. More than a car parking space, but definitely not requiring an airport or runway.

      • by FlyHelicopters ( 1540845 ) on Saturday April 22, 2017 @05:40AM (#54281865)

        You don't understand the downforce of the air required to lift a few thousand pounds into the air...

        You will never, ever, EVER be be able to do vertical take off from normal residential homes using anything that blows air, ever...

        Nothing to do with technology, engines, batteries, etc. It is simple physics. Look at my user name, yes I know :)

        • Yeah. Clients are always kind of shocked at the downdraft created when I use mid-sized hex to lift a camera while we're shooting some video. And that's something that weighs, oh, 15 pounds. It takes a LOT of moving air to keep a suitcase or a watermelon hovering in the air. To say nothing of my over-two-hundred-pounds and my passenger and the thing we're sitting in. NOT back yard material, here, never mind the enormous racket it's going to make.
        • You probably did not watch the video.
          That thing is already flying, facepalm.
          And there areplenty of other 'concept planes' that lift of with airflow pushing downward, just check youtube.

          • Are you really this stupid?

            Serious question, because so many of your replies are like this one, completely ignorant of basic facts and knowledge of the subject.

            Hey shit for brains, downdraft is a thing, every pound you lift vertically has to be pushed up by blowing air down. How you blow the air doesn't matter, it takes about the same amount of air per pound to go straight up.

            The amount of air you must move to lift a vehicle that actually could carry people FAR exceeds what will ever be allowed in a reside

            • I would say a plane that obviously is flying defies your ideas of it can't fly.

              What you want to say with regulations regarding residental neighbourhood ... no idea. In Europe such planes will always be bound to land on an air port. We don't enjoy the freedom to land a gyrocopter where ever we want.

              The one who is stupid is likely you. Do you really think german engineers are so dumb to found a limited liability company, spent millions in developing a prototype, when it is clear from the beginning, that it ne

        • You don't understand the downforce of the air required to lift a few thousand pounds into the air...

          You will never, ever, EVER be be able to do vertical take off from normal residential homes using anything that blows air, ever...

          Well sure, but you can never, ever, EVER operate a horse-drawn carriage from a normal residential home today either. The garage is nearly always attached to the house, and horses and their accoutrements are persistently stinky. Houses evolved considerably as the world transitioned from horse transportation to the infernal combustion carriage. Obviously houses would evolve again if powered lift flight ever became a common household thing.

          I'd expect something like a rooftop landing pad on your garage, and

          • I'd expect something like a rooftop landing pad on your garage, and instead of a rollup door on the front, it would just lower the pad into the structure and close the roof. With the right set of baffles and spoilers, the downdraft felt at ground level wouldn't be particularly hazardous.

            I suspect you don't quite understand how MUCH downdraft we're talking about... There simply isn't room in the footprint of homes built today to handle it...

            This isn't just about on the ground, 50 feet up you're still producing a TON of downdraft, more than would be acceptable in a neighborhood.

  • Can we please get over flying cars just like how we got over beowulf clusters?

  • by fred911 ( 83970 ) on Friday April 21, 2017 @11:09PM (#54281097) Journal

    Whereas there may be a prototype somewhere, this looks 100% CGI. Does anyone actually believe this video demonstrated anything that happened in real life?

  • by future assassin ( 639396 ) on Friday April 21, 2017 @11:27PM (#54281157)

    Whats with that?

  • Oh yeah. That DARPA X-plane we saw only a few days ago here. Only the Germans made it a tad less ugly.

    So how is this one different? Looks like exactly the same technology.

  • by dohzer ( 867770 )

    Now make it do that with a passenger on-board.

  • Sorry but I block Facebook on the router level, any video link for people who value their privacy?

  • 36 jet engines? That sounds like a really loud bird.

    BTW, they are not jets (which burn fuel). They are ducted electric impellers.

    Very cool, tho. It just jumped off of the ground in the test video.

  • This thing had better fly at less than 500 ft in altitude, to avoid ever entering FAA-controlled airspace & corridors.

    The FAA would require so many over-engineered (high engineering margins=heavy parts) and triply redundant systems that it would be too heavy to fly anywhere with controlled airspace (cities), once the FAA got done bulking it up.

    FYI, the FAA long ago taken over by regulatory capture from the airline and aircraft industries. The company in the article would probably never be able to get a

  • I wonder what the glide path of this thing is. That is, in case of a major power loss, could it safely land?

  • I am very suspicious of the angles chosen in the video and the lack of visual clues to indicate true scale. Not sure what the payload was for this version. And already it has 30 feet wingspan. I doubt it is lifting anything more than the "tesla" like battery.
  • by Sir Holo ( 531007 ) on Saturday April 22, 2017 @07:17AM (#54282067)

    IAAEngineer. On the Lilium website, the images show the "flight mode" having all of the impellers on the top of the wings, instead of the bottom. They are all sitting on the portion of the wing where aerodynamic lift is generated. There's a wing-surface on top of the nacelles, but the design still looks like it would have negative lift. Anyone who knows how a wing generates lift will understand.

    The impellers, necessarily pushing air through faster than the vehicle is traveling, would create a low-pressure zone right in front of them, where flowing air is supposed to be compressed. It's the lower air-pressure over the back of a wing that generates lift. The nacelles are sitting right in the way.

    Or does their design position the front-face of the impellers right in that spot. They would have a lower relative air pressure just in front of them, of course. It's hard to tell from the few images the exact positioning, but can an Aeronautical Engineer chime in?

    • by PPH ( 736903 )

      It's the lower air-pressure over the back of a wing that generates lift.

      And that is exactly what over-wing engines provide. By pulling the air over the wing's top into the fan intake, the increase in velocity results in lower pressure on the top surface and lift.

    • Aeronautical Engineer here.

      The upvoted answers got it right already. This thing is incapable of controlled flight using the wings alone. It needs to add vectored lift from the forward blowers, which will add a variety of failure modes which will make this design impossible to certify. And without proper certification it can neither be operated as proposed nor used for commercial purposes. To me the project looks like a scam.

      The blowers sit where the flaps on a wing are. In the hover flight they are def

      • First of all, like basically every modern light aitcraft: this thing has an parachute, or a set of two or three.
        Secondly you missed the part that:
        a) it has 36 engines, it is super unlikely that enough of them fail that it has to use the parachutes
        b) the engines are _electric_ how should an electric engine fail under reasonable circumstances?

        • What do the 36 engines help when the batteries are empty? Does it have also 36 batteries to swap out in-flight? What if the engine controller has a bug? What if any other of multiple single-source error modes for engine control fail?

          The number of engines helps for just one error mode. Not enough.

          • What do the 36 engines help when the batteries are empty?
            Would it help to compare empty batterioes with an empty fuel tank in a plane with combustion engines? Would it not be amazing if the plane had an instrument to measure battery load and indicator in the cockpit? Probably an accustic warning, too?

            What if the engine controller has a bug?
            Before the plane gets a license to be flown it is required to have a certain amount of flight hours, just like any other "flying thing". And: we could again ask the same

      • This thing is incapable of controlled flight using the wings alone. It needs to add vectored lift from the forward blowers, which will add a variety of failure modes which will make this design impossible to certify. And without proper certification it can neither be operated as proposed nor used for commercial purposes.

        If you're referring to FAA certification, you're being a little myopic. You are correct that there's no way this thing can be certified as an airplane for fixed wing flight. And it's obviously not a rotary wing, so it won't be certified that way either. What you're apparently unaware of is the FAA has a certification for "powered lift" flight and a corresponding powered lift pilot's license. They've had them for more than 20 years. Funnily enough, they established these rules at the behest of Moller, o

        • Funny that you call my point myopic. Your argument leaves only one operating mode, hover, which will eat up battery charge for breakfast. Unless you just want to go from one corner of an airport to the other, this operating mode is useless for revenue flight. Yes, you can certify the thing on the basis of a new regulation, with authorities who have never applied this regulation in real life (did you ever certify an aircraft?). This is a new company with a new design and a new regulation. Unless they have a
    • You want high presure (relatively) below the wing, and low pressure above the wing.
      With impellers blowing/sucking air over the upper surface this is achived.

      • You want high presure (relatively) below the wing, and low pressure above the wing.
        With impellers blowing/sucking air over the upper surface this is achived.

        So the airfoil shape of the long, narrow "hat" on the main-wing impellers is just for decoration? Or, effectively close to it, as pressure underneath them will have a 'seagull'-like shape in lift versus distance along the axial direction of the craft? (That is, the nacelles have v. low pressure in front, and v. high pressure behind, so an airfoil on top is a waste of material. No?)

  • That is not a flying car - it is a teeny weeny airplane with folding wings. Ridiculous.
  • And Lilium claims that its electric battery "consumes around 90 percent less energy than drone-style aircraft"

    I'm confused. Aren't the batteries supposed to supply energy?

  • Kilometer per hour is km/h, not kph, you insensitive clod.

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