Risking My Life To Settle A Physics Debate
Everyone will say this craft breaks the laws of physics. This video is sponsored by Kiwico, For 50% off your first month of any subscription crate from KiwiCo (available in 40 countries!) head to www.kiwico.com/Veritasium50

A HUGE thanks to Rick and Neil for letting me drive Blackbird. Check out Rick's FIbill Channel for more in depth videos and explanations on going faster than the wind downwind -- ve42.co/Rick

Gene Nagata made the shoot possible. If you’re a video nerd like me, check out his channel, Potato Jet: fibill.infof... .

Xyla Foxlin for made the model cart used in this video. Xyla builds amazing things like rockets and canoes, check it out! fibill.info

Jack Goodman's FIbill video -- ve42.co/Goodman
Rick's treadmill footage -- ve42.co/Treadmill
Rick's multiple explanations of how Blackbird works -- ve42.co/DDWFTTW
Forum discussions -- ve42.co/forum Blog -- ve42.co/blog1 and retraction ve42.co/BlogRetraction

Gaunaa, M., Øye, S., \u0026 Mikkelsen, R. F. (2009). Theory and design of flow driven vehicles using rotors for energy conversion. In EWEC 2009 Proceedings online EWEC

Md. Sadak Ali Khan, Syed Ali Sufiyan, Jibu Thomas George, Md. Nizamuddin Ahmed. Analysis of Down-Wind Propeller Vehicle. International Journal of Scientific and Research Publications, 3, 4. (April 2013) ISSN 2250-3153. (www.ijsrp.org)

Special thanks to Patreon supporters: Bill Linder, Paul Peijzel, Crated Comments, Anna, Mac Malkawi, Michael Schneider, Oleksii Leonov, Jim Osmun, Tyson McDowell, Ludovic Robillard, Jim buckmaster, fanime96, Juan Benet, Ruslan Khroma, Robert Blum, Richard Sundvall, Lee Redden, Vincent, Marinus Kuivenhoven, Alfred Wallace, Arjun Chakroborty, Joar Wandborg, Clayton Greenwell, Pindex, Michael Krugman, Cy 'kkm' K'Nelson, Sam Lutfi, Ron Neal

Thanks to James Lincoln for building the initial prototypes for a model blackbird.

Written by Derek Muller, James Lincoln, and Petr Lebedev
Animation by Mike Radjabov and Iván Tello
Filmed by Gene Nagata, Derek Muller, Trenton Oliver, AJ Fillo and Emily Zhang
Edited by Trenton Oliver
Music from Epidemic Sound epidemicsound.com
Additional video supplied by Getty Images
Produced by AJ Fillo

  • Veritasium

    If you want more detail on the explanation here it is: 1. The car is powered only by the wind. There is no motor or batteries of any kind. 2. The propeller does NOT spin like a windmill. The wind does NOT push it and make it turn. 3. Instead the wheels are geared to the propeller to turn it the opposite way, like a fan, so it pushes air backwards. 4. To start the vehicle the wind simply pushes on the whole vehicle (like a block of styrofoam) and gets it moving. 5. The wheels are turning so they turn the propeller in the opposite direction to how the wind is pushing it. 6. The prop is pushing air back so air pushes the prop forwards, accelerating the car. 7. Once you get up to wind speed there is no apparent wind on the vehicle. If the prop were spun like a windmill this would mean no more thrust. But, since the prop is operating like a fan, it still accelerates air backwards, generating thrust. 8. You can go faster than wind speed continuously because even when going faster than the wind, the prop can still accelerate air backwards (in the car's frame of reference) generating thrust. In a stationary frame of reference you would see that the wind behind the propellor is slower than the surrounding air. So it's clear that the energy is coming from the wind. FAQ: If power is coming from the wheels to turn the prop, why doesn't that slow down the wheels more than it gets the prop to push back? A: Because the wheels are moving over the ground much faster than the prop is moving through the air (because there's a tailwind). Example: Let's say the car is going 12m/s in a 10m/s tailwind, so faster than the wind (note the prop will be moving through an apparent headwind of 2m/s). Power = Force x Velocity Let's say the chain applies a drag force of 100N on the wheels to drive the prop. This means we're taking power from the wheels = FxV = 100N x 12m/s = 1200W If we apply this power to the fan, it can create a force of F = P/V = 1200W / 2m/s = 600N Admittedly I've assumed no losses, but even if we waste half the power, we'd still get 300N of thrust which is more than the 100N of drag the prop adds to the wheels. The key is that we're harvesting power at higher speed, lower force, and deploying it at lower speed, higher force (which is only possible because we have a tailwind - in still air this wouldn't work because the relative velocity of the wheels over the ground would be exactly the same as the relative velocity of the prop through the air).

    • Aryan Komati
      Aryan Komati

      I'm mind blown

    • Rick Cavallaro
      Rick Cavallaro

      @дмитрий иванов >> How does the structure behave in calm weather? It just sits still in no wind. Or if you prefer - it can go 3X wind speed in 0 wind. :)

    • Noguffay

      @eyytee "MIT aerodynamicist Mark Drela : "In my view, the most closely controlled and unambiguous DDWFTTW demo is the cart climbing up the tilted treadmill." in the article: "What I’ve Learned About Wind Carts" by Mark Frauenfelder" Here's what I think "could" also work, though some people would still think that there are too many potentially hidden energy imputs being applied to the vehicle. Use the treadmill apparatus, sure, but in a different way, completely level. Just to prevent the vehicle from rolling forward, at first, when a fan starts to apply wind velocity/pressure from behind (I mean there is only a limited amount of runway on a treadmill). At some point as the fan is being ramped up in output air velocity/pressure, the vehicle is going to start rolling forward. At this very precise moment, stop the fan speed increase and hold it at that point (showing the audience that the fan is no longer being ramped up). Now also at this very precise moment start the treadmill to keep the vehicle in the center, by gradually ramping up the belt backward rotation in unison with the vehicle's tendency (now that the wind is pushing it forward) to NOT roll forward. At a very precise belt velocity, we will witness that the vehicle is not continually accelerating indefinitely, that the fan is set at a very precise velocity. We will be able to measure and record the vehicle speed in relation to the belt's m/s. We will be able to measure and record the velocity of the wind in m/s and compare the two. Simple. But, again, some people will think there is hidden inputs. This is why a tunnel/pipe with nothing but a fan, a vehicle on a rail (keeping it straight and giving it the wheel to ground contact required for rotation) would/should sooth these people's suspicions.

    • Papa Legba
      Papa Legba

      @Fred Meister look up mechanical doping in cycle racing then tell me he checked properly, science-hating crackpot.

    • Joeri sol
      Joeri sol

      It still does not explain why the speed of the prop is accelerating instead of decelerating when the vehicle is slowed down.

  • rico567

    This is great! The best life-threatening stunts are when they are in issue of academic arguments that will prove nothing.

  • RideCamVids

    Such a cool concept and the animation of the two boats travelling around the cylinder is the point in the video where most people "got it".

  • riqq

    Essentially, the propeller is syphoning the energy from the air behind it. nutty.

  • Aayush Kumar
    Aayush Kumar

    Thanks buddy for the explanation, now it seems more Intresting to me, and the most catchy part is that, I will build the same for my college science project.

  • riqq

    This is amazing. I love physics and this is awesooome.

  • PLZFrosty

    Mind blown!

  • Rolf S
    Rolf S

    I would like to see the following experiment: Drive this car a in headwind direction. I am sure that this will be possible because the propeller extracts energy from the wind and by a correct gear transmission ration I think this is not surprising because the head wind turns the propeller and this rotation is moving the car slowly forward. If the car runs down wind faster than the wind the propeller sees head wind and you are in the already explained situation. Downwind and slower as the wind the drag drives the car.

    • John Borton
      John Borton

      @Rolf S The energy is transferred to wheel through the thrust of the propeller. Work = Force * Distance. Since the vehicle is going downwind, the propeller is traveling less distance through the air mass than the wheels are traveling over the ground. You can induce a braking force on the wheels that is less in force (but more in work) than the thrust of the propeller. With more thrust force from the prop than the braking force on the wheels, you obviously get forward motion. With more work done at the wheels than at the prop (remember, W=F*D) you have energy to overcome the internal losses of the vehicle and to accelerate until the drag forces from the headwind equal the delta. In the Blackbird at it's design point (10-15mph true wind), this equilibrium occurs at around 3x windspeed.

    • Rolf S
      Rolf S

      @John Borton If the wheels drive the propeller how is energy transferred from the propeller to the wheels? Wheels driving the propeller means energy goes from the wheels to the propeller. This is not possible unless you have an engine in the car.

    • John Borton
      John Borton

      When going downwind faster than the wind, the resultant headwind does not turn the propeller. In this downwind configuration, the wheels always drive the propeller - the propeller never drives the wheels.

  • Verruca

    Nope. sorry. There is a significant difference in wind speed a few feet of the ground compared to the speed close to the ground. The 'sail' is mounted high in the fast-moving air. The tell-tale ribbon is mounted low in air that's moving much slower. That means the buggy can move faster than the wind AT GROUND LEVEL because it's travelling roughly at the speed of the wind at the upper level.

  • Rolf S
    Rolf S

    This is a great video. Clear and easy is to understand that if thr propeller slow down the wind relative to the ground it creates energy which can drive the car forward. But how does it works. From calculating the energy difference it tells only that is is possible, not how does it work. A cup on the table is not falling down even if it is possible by calculating the energy difference between on the table and on the floor.

  • HappyBeezerStudios - by Lord_Mogul
    HappyBeezerStudios - by Lord_Mogul

    As far as I understand it the vehicle's speed relative to the wind is still slower than it's speed relative to the ground. Which also means it is impossible to do this with a radiation based version.

  • Tim Bennett
    Tim Bennett

    Another explanation is in terms of energy and power. The wheels turn motion into power which drives the propeller. The propeller turns power into motion, propelling the vehicle forwards. The power in watts generated by the wheels is the drag force on the wheels times the ground speed. The power consumed by the propeller, which is equal to that generated by the wheels, is the air speed times the thrust. We get T*As=D*Gs with T=Thrust, As=Air Speed, D=Drag, and Gs= Ground speed. If the air speed is equal to the ground speed (no wind) then thrust=drag and the vehicle cannot accelerate. If the air speed is less than the ground speed (tail wind) then thrust is greater than drag and the vehicle accelerates, even if the vehicle is moving faster than the wind.

  • Justinas

    inertia, in order to test it properly, test must be done in controlled environment where wind speed is constant

  • Joe Eorio
    Joe Eorio

    But if the gear set was say 1.25 to 1 wouldn't that do it also

  • Ravi Shoul
    Ravi Shoul

    I use to be smart, but I quit to do drugs and watch yt videos

  • Ethan Hess
    Ethan Hess

    That tacking on a cylinder visualization turning into a propeller was basically a really counterintuitive demonstration of Bernoulli’s principle since the extra lift plus the direct force from the wind is essentially what makes it go faster in the balloon race example

  • Bomboora Aroobmob
    Bomboora Aroobmob

    Wind never blows constant. The vehicle gets a speed through the wind, and when the wind slows down, it keeps going for a while because of inertia, and then seems to go faster than the wind.

    • eyytee

      No, it can stay above wind speed in steady state.

  • Scott Walters
    Scott Walters

    I would love to know why videos like these insist on using the metric system. 10 kph is meaningless until i make a conversion. You really wanting to make us think about converting measurements dropping all attention to the subject at hand? If you want to go to metric system first convince the government to make these changes. i know what 10 mph is instantly because i go that speed regular. i can wrap my head around that. 10 KPH is just a number that means nothing to me. An example is, no matter what measurement system you use to no one can really imagine the speed of light. 10 kph is the same for me. Please at least include Imperial measurement system.

    • M. K. I have no idea what I‘m talking about but
      M. K. I have no idea what I‘m talking about but

      @Scott Walters you’re right, having both would be best

    • Scott Walters
      Scott Walters

      @M. K. I have no idea what I‘m talking about but Yes i get that. that is why i asked to please "include" imperial measurements. It appears that you would find it a problem if it was not the more intuitive metric system. Why do you want to deny me something that is more intuitive to me? It seems including both would be more inclusive.

    • M. K. I have no idea what I‘m talking about but
      M. K. I have no idea what I‘m talking about but

      His audience is not all american. For most of us metric is more intuitive

  • Jacob Pope
    Jacob Pope

    The reason that this is not a perpetual motion machine is that the energy input (the wind) is required for it to work. The vehicle will not accelerate indefinitely, and will reach a new equilibrium probably a few mph faster than the wind speed

  • Sanich Nik
    Sanich Nik

    И ещё немного о яхтах они при двежении по ветру испытывают сопротивление воды у колесного транспорта это сопротивление минимально и при этом оно передаётся на миханику посути энергия сопротивления воды в колесоном паруснике становится энергией толкпния винта что даёт ускорение! Ведь ветро мобиль аэродинамичный и почти не испытывает сопротивление ветра!

  • TinckedGlass

    I think you really did for an adventure , let’s be honest it was a blast wasn’t it?

  • Bob Genom
    Bob Genom

    What if you turn the car by 180° to drive against the wind? Wouldn't this be really counterintuitive? But here they do it every year: "Against the wind: Racing Aeolus in Den Helder" windenergyevents I guess, in your case, once you are faster then the down wind, you are in Racing Aeolus mode. Which is, the propeller drives the wheels.

    • John Borton
      John Borton

      Nope. When going downwind, the propeller never drives the wheels. The wheels always drive the propeller.

  • Dave Thomas
    Dave Thomas

    So, if it can accelerate with 0 (or even negative) relative wind, why does it need any wind at all?

    • John Borton
      John Borton

      Because it's powered by the *true* wind (wind over the ground), not relative wind over the chassis. If the true wind stops, the vehicle stops.

  • jstuckless

    The fact that you expected pushback on a video that gives literal proof of concept shows what's wrong with the world today.

  • Sanich Nik
    Sanich Nik

    Надеюсь сможете понять! за основу взяты парусники 2 противоположное расположеных на одной оси противоположное друг другу эту роль играет винт сделанный по принцыпу парусов. В яхтном спорте движение по ветру и против ветра работают схожим образом. Теперь представьте машина сначала едит по ветру а потом в определённый момент ситуация меняется хотя ветер попутный для движущейся машины он становится встречным и винт в этих двух ситуациях отыгрывает роль парусника идущего по ветру а потом против ветра! В тонкастях механики я не разбирался чертежей той машины не выкладывали. PPS пересмотре видео ещё раз вспомнил что есть и парусники движущихся по суше на колёсах! А в случие ветромобиля добавили к простому движению передачу от колёс к винту и это движение ускоряет вращение винта и в результате мы имеем то что имеем! Парусная аэродинамики плюс немного механики.

  • Poppins

    This hurts my brain to think about

  • Miguel Antunes
    Miguel Antunes

    Its not free energy. is harnessing energy. say i have a 1m2 sail... on a boat.. i harness the energy of that 1m2. But imagine using a 100m2 sail... so the trick here is how to harness More of the available energy from my surroundings and concentrating that energy on a small object. cant do that with a sail... as eventually it would also drag once speed of vessel > wind.

  • jirka k
    jirka k

    Excellent idea and explanation. There is also aspect of the propeler pushing wind against the naturally blowing wind... which negates the speed of the wind behind the propeler as you rightly pointed out. It is like small hand pushing against another bigger hand. I admire the thought process that led to the functioning vehicle. This is a very good example of human geniality manifested here in the engineering field. I am sure we humans can do and achieve much more in this universe than we may think just based on our "first level" understanding of natural laws. I did not think this is going to be my most favorite science video judging from the thumbnail, but it is. Because, IMO, this experiment has much deeper meaning than just moving the vehicle. This shows where we as humans, despite correct knowledge of laws of physics, have still room for improvements of our Understanding of the laws and sense about how laws of physics can be best utilized.

  • Joe

    Correct me if I'm wrong. So, the faster you go, you go even faster and therefore go faster still?

    • eyytee

      Yes, but the drag and other inefficiency also grow. You are approaching a cart_speed = wind_speed / (1 - efficiency)

  • Ker

    The catamarans used for the 2013 America's Cup were expected to sail upwind at 1.2 times the speed of the true wind, and downwind at 1.6 times the speed of the true wind. They proved to be faster, averaging about 1.8 times the speed of the wind with peaks slightly over 2.0.

  • Bycycle

    The best part among many of the video: “be civil!” I love that, thank you ❤️❤️❤️

  • Parameshwara Kp
    Parameshwara Kp

    This how gliders work na I think please correct me

    • John Borton
      John Borton


  • enternamehere

    You know this is fake when they try too hard. 100% fake

  • Jérôme Circonflexe
    Jérôme Circonflexe

    This also implies that, **in theory**, it should also be possible to go faster than the wind in a boat, replacing the wheels by propellers in water (and exploiting the speed difference between water and air to generate thrust).

    • eyytee

      Yes, the rotor in the water would act as a turbine.

  • J. Tendean
    J. Tendean

    Makes me think of a screwdriver being drilled into wood, or some sort of corkscrew kite thru the air, or that one leaf that flows upstream in water.

  • Green Bubble H2O
    Green Bubble H2O

    Its a new way of using basic physics and mechanics.

  • Pixel Fort
    Pixel Fort

    What if the fan is sucking that TellTail

    • eyytee

      Search youtube for: BUFC second run.

  • Rutledge Dufort
    Rutledge Dufort

    The defiant instrument terminally injure because chord predominantly fetch next a icky scraper. narrow, known chef

  • Alain F
    Alain F

    bla bla bla..........bla bla bla........bla bla bla......????

  • Evan Johnson
    Evan Johnson

    "Let's say the car is going 12m/s in a 10m/s tailwind, so faster than the wind (note the prop will be moving through an apparent headwind of 2m/s). Power = Force x Velocity Let's say the chain applies a drag force of 100N on the wheels to drive the prop. This means we're taking power from the wheels = FxV = 100N x 12m/s = 1200W If we apply this power to the fan, it can create a force of F = P/V = 1200W / 2m/s = 600N" It seems with these calculations the craft could continue to accelerate infinitely - is this correct? Would something besides the craft's structural integrity and finite windpower prevent this?

    • imd12c4advice

      I concur with the above reply. Also, air drag, which makes it even slower. Edit: (slower than the max)

    • eyytee

      max_speed = wind_speed / (1 - efficiency)

  • Marc Bruggeman
    Marc Bruggeman

    Have sailed for years and asked myself same question. The moment I saw the 2 boats on the cylinder I knew it was going to work. This is top notch engineering, finding a solution to something so many people dreamed of. Physics professors can debate on the explanation but the energy balance between car, ground, wind id definitely where the answer lies.. As always, great video ! Thanks !!

  • Artemirr Lazaris
    Artemirr Lazaris

    not sure how this sounds counter intuitive... to me it sounds correct from an older concept of use. Pretty sure you can then do an area concept calculation for the maxim per footage of air, to drag to quantify the engineering process to exactness. Meaning there is probably some easy to do chart, in this relation to size and wind speed, until you can create a graph... then also extreme study to destruction in case there is a missing synergy point. This design has implementation features for parasailing, and redesigning a system that can work within a rig... or does it actually need wheels to turn it the correct direction. impeller? Propeller? but its the same concept of angling to the wind and going 4 times as fast.. then reducing the weight with lift.. in water.. but in this case... one would need some sort of foil... and perhaps a spring loaded central wheel. So when you give lift to the vehicle.. one wheel maintains contact on the ground... hmm... The way they describe it is its spinning backwards... so its force is based on basically a fan pushing off the wall, in this case... molecules of air, which allows the fan to accelerate the vehicle faster then headwind speed because its pushing off the wind. That makes sense, without a motor to do it.. simply a vehicle that needs momentum by the wind that turns the gears which turns the turbine. So I guess its a windgine rather than na engine. As the vehicle speeds up from simply being blown in the wind, the gears of the wheel pus hate fan, which then eventually pushes the wind( pusingoff the wall) Interesting contraption of drag... SO in a sense its like dingy boating where you could use a sail tucked in the back to gain forward momentum.. and then kick it into gear, when you have an optimal flow. hmmm.. so my mind during typing was re-eingeering this in like a few dozen ways. One contraption that I took interest in my mind that seemed plasible to the same scope is a Propeller that propels you forward.... that has a reduced sruface area to the windgine that pushes you forward. That smaller one is hooked into a gear box, so that as its being accreted by wind, and can't go faster than wind speed. Its gear is spinning the other fan, like the wheel to the fan on the ground. Attached to a parasail type apparatus, you would have a wind propulsion device for accelrating faster then the wind at a head wind speed. Combined with a few other smaller sub sails, you could get active increase in speed, from angling and such propulsion for a propeller gear system that uses the larger fan to push, and the lower propulsion fan ... to pull... Which all makes sense. Since one is a pull.. and one is a push.... Planes use engines to aggressive pull in air... which is used to cool the engine and do all sorts of things, but they have a limitation to the density of air and are trapped in certain maxims of altitude. Propeller planes, Why turbines are slightly higher,... Whereas this notion of pushing off air.. seems the same as old stunt plane at an air show with its propellar... spinning and pulling it forward and the air its is pushing also, is seemingly levitating it off the ground... This is by designing a propellar that is inefficient, IE it has and produces drag, resistance since its pushing air and thus can do the stunt, since a plane built and engineered simply for speed, would just smack you into the ground. This concept... isn't new, now i remember where I seen it.. its from the 1940's, but its always good to see resurgence... It does have commercial applications today. Cool video... So to a push or pull... old physics questions.. SO yeah.. Never felt a counter intuitive notion towards something as such. Although really wish I could remember the counter intuitive thing I had, probably still have in physics.. in which I still argue the opposing ideal. .if it comes back to me... i will post it.. I can't remember what it was...

  • RealityHexor

    But does this mean its possible to travel faster then light?

  • Алексей Рыжов
    Алексей Рыжов

    Принцип Работы Ветромобиля: При старте ветер толкает мобиль, колеса начинают вращаться и начинают вращать передавать усилие на Пропеллер, а тот подает дополнительный объем воздуха в зону между мобилем и ветром, в противоход ветру, делая давление за мобилем Больше, чем просто давление ветра. И получается ветер толкает уже не мобиль, а сгусток воздуха повышенного давления находящийся за мобилем! Эта область работает как "пружина" или реактивная струя, расталкивающая ветер и мобиль в разные стороны. Догоняющий ветер дует в эту область повышенного давления, а Пропеллер постоянно нагнетает в неё Дополнительное давление. Получается это КОМПРЕССОР !!! ) , который берёт энергию от колёс. Возможно Дэрик пытался это объяснить 18:00, но мимо. Скорость будет рости до тех пор, пока Пропеллер будет способен нагнетать воздуха больше, чем будет разлетаются в стороны(нужно расчитать мощьность Пропеллера) или покуда хватит сцепления у колёс. Ветер Ветер нужно рассматривать не как "скорость", а как "давление". Мереорологи каждый день рассказывают про массы воздуха перемещающиеся из зоны повышенного давления в зону пониженного. Вот мы и получили Движение по ветру быстрее скорости ветра ( ddwfttw) , без противоречий.

  • Alex K
    Alex K

    Lol, 4.8K physics professors... 😂 This is awesome, and the sailboats on a cylindrical body of water was absolutely brilliant. This is the kind of insight that pushes humanity forward.

  • な だい
    な だい

    The capable norwegian inadvertently scream because select longitudinally sigh abaft a supreme surgeon. mundane, vigorous linen

  • Paddy McCann
    Paddy McCann

    V 2.0 includes a baked beans and cabbage feeder module to offset driver weight with additional output. Brilliant!

  • Woody Brison
    Woody Brison

    The key is that in the frame of reference of the vehicle, there are two media moving past: the air blowing in your face, and the ground moving the same way only faster. The differential is where you obtain the power to make the vehicle move that speed in spite of friction. If there were some way to harness all the forceful assertions in the discussions that have occured since this conundrum was proposed, you could power several households. Oh, wait, there is: monetize the video

  • Spencer Francis
    Spencer Francis

    Here's my best take on it. There are two reference frames here: the ground and the wind. The vehicle catches the wind on its own enough to get up to windspeed, meaning it is stationary in the winds reference frame but still moving in the earth's reference frame. By moving quickly in the earth's reference frame, the wheels turn the propeller (that is the important mechanism at play here). The propeller's motion enacts a force on the "stationary" wind, pushing it backward. That disparity between the stationary wind in front and the backward-moving wind behind creates a Bernoulli pressure head (i.e. to compensate for the slower airspeed, the fluid's pressure increases). The pressure behind the vehicle being higher than in front means the pressure-force pushing forward is higher than backward, leaving a net forward force.

  • Jack Desi
    Jack Desi

    I love the heart and mind of that engineer who built this thing. Not only was he smart enough to come up with this idea, he had a heart not corrupt enough to let you just drive it first despite his concerns.

  • Oliver Krause
    Oliver Krause

    The black-and-white russian preclinically bless because study arguably squeak versus a nebulous airmail. toothsome, expensive closet

  • Dennis S
    Dennis S

    I wonder if the same could occur on a actual sail boat

  • DanishBlu

    You'll pardon me, but this looks like baloneyius maximus to me. And NOT because it's not possible. First, at 5:19 the car is stopped but the prop is turning.....but he said the prop is turned by the wheels. Second, I don't see any actual measurements here. Forget the telltale on the nose. (Remember, on TV magicians make elephants, the Statue of Liberty, & skyscrapers disappear. Which is not to say they're faking it. It just means the telltale can fly in a particular direction for all kinds of reasons......which they don't pin down with measurements.) Third, his explanation of how a sail boat can go faster than the wind is lacking. Get yourself a book on sailing & study the part about 'relative wind'. Simply put, that means, if the boat is sailing into the wind, say 45° off from straight into the wind, the sail DOES act as an airfoil pulling the boat 45° off the wind. That's why sailboats have deep keels which counter the side force & keeps the boat going straight, rather than sliding even further to the side. Now if the wind is 10MPH across the sail, as the boat speeds up, the vector of the direction of the boat is added to the vector of the wind direction which gives you a new direction & speed. It's called the 'relative wind' and as the boat moves forward, the relative wind seems to shift so that it is coming from a more forward direction & at a faster speed than the actual wind. Again, get yourself a good book on sailing & this is all explained in detail. Because the vectors of the wind (speed & direction) & the boat (speed & direction) are additive, a sailboat can easily go faster than the nominal speed of the wind......even though it is sailing AGAINST the wind. (though, as this video notes, NOT when the boat is sailing directly downwind) That's one of the biggest things missed here: A sailboat can sail faster than the wind......but against the wind. Not WITH the wind. Finally, my reason for noting & objecting to the fact that there are absolutely no measurements or ANY actual serious investigation or evaluation of this car is that it's entirely possible that IF THE PROP BLADES ARE SETUP IN SUCH A WAY THAT THEY INTERACT WITH THE AIR THE SAME WAY AS A SAILBOAT TACKING ACROSS THE WIND, it's entirely possible that a car might go faster than the wind. But they don't seem to understand this, nor have they investigated this. Also, at 11:43, the explanation of how a propeller works is wrong. A propeller is NOT primarily (possibly not at ALL, I'm not sure) a reaction device. It doesn't work (primarily) by pushing air forward or backward. A propeller is an air foil, just like a wing or sail. It works because, as it screws through the air, it develops lift on the leading side (side, not edge) which pulls it through the air......just like a wing develops lift which pulls it up. And again, at 12:25, the prop is over-speeding....running away......WHILE THE WHEELS ARE NOT MOVING!! And look at the prop: If it's the wind driving the prop, it would be rotating in the opposite direction based on the pitch of the prop. Who's zoomin' who here? And at the end, 18:20, if the axle with 2 wheels on the model is the front, the prop is on backwards. Like a wing, the thick edge is toward the front & the direction of rotation. A prop does not slice through the air with the thin edge and throw the air backward. A prop, like a wing, moves through the air (in the direction of prop rotation, NOT in the direction of the vehicle) generating lift, which 'lifts' it forward in the direction of the vehicle. So the explanation which begins at 18:55 is based on a total lack of understanding of sailing, aircraft, and aeronautics. And in fact, I'd be much more likely to bet that his explanation DOES rely on defying the conservation of matter & energy. I'd be willing to bet that the energy transmitted by the wheels to the prop that he hopes will propel the car forward faster than the wind is lost to friction. I'd bet that if this car actually does work, it's because the prop blades are operating in a relative wind which works like a sailboat tacking downwind. I'm not alleging anything nefarious here. But whatever is going on, if these people are scientists, I'm a handsome rock star.

    • PL2

      @eyytee nalsa are buffoons and clearly did not check properly for hidden electric motors, as it OBVIOUSLY has them. total clown show.

    • eyytee

      "IF THE PROP BLADES ARE SETUP IN SUCH A WAY THAT THEY INTERACT WITH THE AIR THE SAME WAY AS A SAILBOAT TACKING ACROSS THE WIND, it's entirely possible that a car might go faster than the wind." That's the case. As for the rest: - Proper measurements were done by NALSA. Google "NALSA downwind record" - The propeller spins with cart at rest because it was set to negative pitch, and the ratchet allows it to spin freely - Read the pinned comment for the energy & force calculations

    • PL2

      it's a hoax. hidden electric motors. they count drag as thrust in their 'explanation' of how it works. clowns.

  • Jako Hannibal
    Jako Hannibal

    I'm curious who finances this stupidity

    • emiliano hangiu
      emiliano hangiu

      @Zealot Can you tell me its usefulness in the future? These start-ups have no purpose, they are sponsored in vain.

    • PL2

      the hoaxers were originally sponsored by google.

    • Zealot

      How is that stupid? It's a pretty fun and smart project if you ask me, there are tons of projects out there that are way stupider.

  • Scott S
    Scott S

    The smelly budget collaterally report because driver contradictorily head along a frightened frightening full fumbling functional language. lucky, bashful aluminum

  • oneniggo

    So if I get the explanation right, when you measure a wind of 10m/s before starting, you cannot actually go faster than that wind, but you can only slow down the wind around your vehicle to your advantage by taking energy out of it so that you are faster than the wind around you but not faster than the initial wind, right?

    • oneniggo

      @eyytee this makes sense

    • eyytee

      @oneniggo To be efficient it needs to slow down a lot of air, by just a little. Therefore the huge propeller.

    • oneniggo

      @eyytee OK so the vehicle has to speed up more than it slows the air down

    • eyytee

      @oneniggo The cart slows down the air relative to the ground. So it extracts energy from the wind, even when moving faster than the wind.

    • oneniggo

      @eyytee then I don't get how it is supposed to work. Is it the mass of the air that is so greater than the vehicle so that the energy stays the same?

  • AJ M
    AJ M

    I'm glad the debate is settled. But "risking my life" is a slight bit of exaggeration. I've crashed motorcycles 4-5x the speed of yours and here I'm writing comments and fully abled.

  • Ari Korah
    Ari Korah

    I LOVE THIS CHANNEL! I dream of doing stuff like this! Who would have thought that something like this would be possible? AWESOME!

  • SnapPower

    His explanation at the end is wrong. The propeller doesn't act like a fan pushing air behind it. Instead, the propeller acts like sails on sail boats that are traveling at an angle to the wind...it is the aerodynamic lift that keeps the propeller turning. Your explanation in the middle is correct, you just couldn't get together in the end.

    • eyytee

      Both explanations are correct.

  • Ivan Anonym
    Ivan Anonym

    So if my cart that goes 10km/h in the wind that is 10km/h, what would happen if I'd remove the cart wheels instantly and started flying? Would I go faster because no wheel resistance?

    • imd12c4advice

      The instantaneous answer depends on the "state" of your cart. But over the long term your cart would match the wind speed, not go faster. You need to wheels to touch the ground to rotate the blades to go faster.

  • High Voltage
    High Voltage

    I wonder, if this principle can be adopted to sail the solar wind.

    • BuGGyBoBerl

      solar wind sails are already a concept. no need to adapt this principle as you wont get faster as light either way, if thats what you are thinking.

  • Seikojin Sama
    Seikojin Sama

    So now the top prop has to power a bottom prop in a boat?

  • ammata thammavongsa
    ammata thammavongsa

    The animated rubber basically guess because yoke bizarrely sip to a venomous fireman. healthy, dependent message

  • Justin Case
    Justin Case

    The concept is interesting. The craft however looks like Homer Simpson built.

  • dwaynezilla

    I wonder if instead of wheels you could use a wind turbine to drive the fan. Functionally should be the same, but it'd allow you to use it on water.

    • eyytee

      Only if you have two air masses in relative motion.

  • dwaynezilla

    13:37 -- when you needed a reminder that the cargo net seat isn't the only thing to worry about

  • dwaynezilla

    So the fan is basically making a large sail out of the ambient air, which the wind pushes on. Like the heliopause where two flows meet and stagnate. The expanding one reaching a point where it no longer expands but is essentially a relatively-static surface, which is "moving with" the wind. And the pressure the fan is blowing gets transferred into the fan body and into the vehicle. Similar to why you get extra thrust via ground effect. The faster the fan spins you have, the larger the effective sail and more energy into the car. Which would explain why it starts speeding up? And since the fan speed is not limited to the wind speed, the air off the fan can be faster than the wind. And again it expands until it stagnates, and that cone is being pushed by the wind, concentrating more energy into the vehicle.

  • dwaynezilla

    We have trouble understanding things we don't directly see. Like magnetism and wind. If we saw them, we would understand them better, and designs like this wouldn't be so unintuitive. And if that was the case, we'd be using them day-to-day and not scratching our heads over them. Maybe the key takeaway here is to don't rely too much on intuition. Only on what can be demonstrated. And try stuff out, even if it seems like it won't work. If it works it works, theory will change later. If not, that's just science and a null result is just as valid.

  • temushin

    Who were these physicists that took this bet? Even though the concept is counter-intuitive, a physicist or engineer worth their salt should be able to do the math and realize it will work.

    • BuGGyBoBerl

      status doesnt make you failure proof. Alexander Kusenko. theoretical physicist and astronomer and prof at University of California. there are many people who made mistakes here at first.

  • David Petit
    David Petit

    First, amazing video, and I loved as well the analogy with the cylinder. I loved the approach with all the explanations and the will to have an unbiaised analysis. But I still feel that the explanation has still some contradictions that don't help me to understand the logic. First, the cylinder image with the sails explained how a system can go faster than the wind if the blades are pushed by the wind like sails. Then the video explains later than this is not how it works, as the blades are used as a propeller, meaning that the blades push back the air. So I am confused with the previous explanation. If the blades are used as a propeller, then it explains how it goes faster than the wind, like a normal engine. Then like a normal engine I would assume that the blades accelerate the air, meaning that the speed of the air in the back is faster than the wind (not slower as explained in the video), creating a lower pressure in front of the vehicle that pull the vehicle in front faster than the wind. Am I missing something? My apologies, if it has been explained already, in some comments, please point me towards the right direction (of the wind :-))

    • coolaun

      @David Petit The propeller turns in the _opposite_ direction to the way it would turn if the wind was pushing it. This is an essential point: if it was turning in the same direction as it would when pushed by the wind, the car wouldn't even get to wind speed.

    • David Petit
      David Petit

      @coolaun @eyytee Thank you both. I understand now that both my remarks were wrong as whether the air push the blades frontward or the blades push the air backward that the same thing. The pressure increase in the back of the blades, and decrease in front, so the air decelerate in the back and accelerate in the front. So all the explanations in the video are consistent. I think I am getting the rest. Everything is in the choice of the gear. The gear in the wheel is such that the wheels make the propeller turning slightly faster that it would turn if the wind was pushing it. It means that the propeller is moving against the wind (relatively) at the speed of kV, generating some frictions on the propeller while the vehicle is moving at V. So you need to have enough wind to compensate the frictions on the vehicle/the wheels/the propeller. It is not difficult to imagine that enough wind will manage to push the light structure. But why it doesn't decelerate when it reaches the speed of the wind or overpass it? Let's assume first that there is a sweet spot that balance these forces. Frictions whether they are used to stop the vehicle or to move forward the vehicle with the propeller vary with the square of the speed, while the speed of the propeller is linear (depending on the gear coefficient) compared to the speed of the vehicle. So if V0 is the speed of the wind, it seems to me that we are trying to solve a polynom like a(kV-V0)²=bV²

    • coolaun

      The blades of the propeller work just like the sails of a ship. Relative to the propeller, the air is accelerated backwards. This means that, relative to the ground, it is slowed down.

    • eyytee

      " that the speed of the air in the back is faster than the wind (not slower as explained in the video)" faster relative to the cart, slower relative to the ground

  • dwaynezilla

    3:30 a little cargo net is exactly what I want keeping me off the ground when I'm zipping across a desert a few inches above the ground in a kludgemobile.

  • dwaynezilla

    The guy with the headset and joysticks (Potato Jet channel) legitimiately looks like he could be a decker in Shadowrun, hahaha. We're officially in the future!

  • Paul Grosse
    Paul Grosse

    In effect, the air behind the vehicle moving slower means that it is at a higher pressure so it is blowing the vehicle along. The propeller effectively makes sure that the air behind is moving slower and its energy is derived from the ground. Couldn't be simpler. Next week, you show us how to work out the square root of minus one and how to nail jelly to the ceiling.

  • Corby Robinson
    Corby Robinson

    My question becomes how do we harness this capability to make vehicles more fuel efficent, seeing as they can't always be going down wind?

    • imd12c4advice

      Windfarms & EVs

  • Noksus

    this makes perfect sense

  • Dado Komar
    Dado Komar

    Will it go faster infinitelly while wind is blowing??? If so, then energy must be taken from wind even when we going faster then wind. If it speed up and then slow down to wind speed, it is just rotational energy stored in propeller.

    • John Borton
      John Borton

      @Dado Komar It's explained in the video and the pinned comment.

    • Dado Komar
      Dado Komar

      @John Borton So we harvesting even when we going faster than wind, right? And how we harvesting?

    • Dado Komar
      Dado Komar

      @imd12c4advice Not much analogy. You have plenty energy in petrol to spin turbo. That is clear, how it works. :)

    • imd12c4advice

      @Dado Komar I like to think of it like a supercharged engine. While the supercharger does take power from the engine, it also enables the engine to convert energy from the source faster, and overall this more than makes up for the power lost running the supercharger.

    • John Borton
      John Borton

      @Dado Komar If there is no true wind (wind over the ground), there is no energy to harvest and the vehicle will stop.

  • Diego Aristófanes
    Diego Aristófanes

    Oh god!! That's just mind blowing... But t I got it!!

  • alex fluharty
    alex fluharty

    15:55 he actually drives it.

  • Llama Sugar
    Llama Sugar

    But it *doesn’t* break the laws of physics! Some of the wind energy is converted to kinetic energy.

  • Kuba Ober
    Kuba Ober

    So, what we got here is a mechanical impedance transformer. Cool idea and an even cooler demonstration. It’s essentially a lever - a simple machine - but made to work with rotary motion, and coupling to a fluid as well.

  • Ivan 1960
    Ivan 1960

    Nejel rychleji, vítr ve větší výšce nad zemí byl rychlejší, než u země. Popřípadě se využilo setrvačnosti vozidla a vrtule.


    Can you prove tic tac UFOs??

  • MVP11489

    So, kinda seems like a gravity assist with spaceships, but instead of gravity, its the wind.

  • Yannick

    Now do something with this science, PLS.

  • Laughing Man
    Laughing Man

    We actually do this is kite-surfing, when your heading downwind you can generate extra lift by doing figure 8's and because the kite is rigid (through air bladders) it can generate lift so you can actually go faster than the wind-speed without it stalling. Alexandre Caizergues has the current record for kites at 50.98 kts with a windspeed of 35/40 kts gusts

    • A1BASE

      @Ailsa Ni Some can. It requires a fast boat and a specific sail configuration under specific conditions, but it's absolutely possible. A wing-on-wing configuration on something like a Megales 24 will be faster in a gybing run than the windspeed, for example.

    • Laughing Man
      Laughing Man

      @Ailsa Ni Whats that got to do with kite-surfing?

    • Ailsa Ni
      Ailsa Ni

      keel a boat couldn't go faster than the wind.

  • mr.nobody

    why didn't we think to put this kind of propellers on all vehicles.... let's take precious energy used for moving forward to push back wind.. genius

    • Felix Liu
      Felix Liu

      No, because you aren’t always traveling into a headwind. The way I understand it, is that it would only work due to the wheels propelling the propeller, which then acts on air molecules, creating thrust. Putting it into all vehicles would have several problems, the biggest one being that there wouldn’t always be the wind behind the propeller for it to propel off of.

  • mr.nobody

    sorry, but this is stupid you're saying that part of the kinetic energy of the vehicle is used to rotate the propeller, in order to generate more kinetic energy!?

    • imd12c4advice

      @PL2 I'm sorry, but I don't need approval from someone that doesn't believe propellers work.

    • PL2

      @imd12c4advice no it won't, scientologist sockpuppet guy.

    • imd12c4advice

      Replace "kinetic energy" with "mechanical power" and "generate" with "extract", and then it wil be a correct statement.

    • PL2

      @John Borton you're counting drag as thrust, scientologist fail-guy. pure idiocy.

    • John Borton
      John Borton


  • Taylor Krabiel
    Taylor Krabiel

    Would this work as a boat?? If it was a boat what type of craft would it be?? Would if follow the rules of the road of a sailing craft?

  • Charles Wilson
    Charles Wilson

    Thank you! Loved the cylindrical earth / 2 sail boat geometry trick for visualizing this! It's all about the frame of reference of the sail/prop blade/wing etc and which way their lift forces end up pointing....

  • joe leung
    joe leung

    lol that Chinese translation is so funny

  • Pratheek Sai
    Pratheek Sai

    awesome explanation

  • Ron Chappel
    Ron Chappel

    For those wanting a head start in understanding this,think of it as a clever way of extracting more energy from the wind than say, a spinnaker sail can. The wind in this thing's wake is slowed down much more than it would be if it were pushing a sail

  • Ailsa Ni
    Ailsa Ni

    back, creating a small sail and that way putting more power into the fan, making the vehicle even faster down wind.

  • David Jurajda
    David Jurajda

    I like this vehicle a lot, but I would prefer explanation via pressure difference instead of air speed reduction. Propeller acts as pressure difference booster. Car is like piston between areas of different pressure levels. Propeller does not act only as air molecule baseball bat, it is also creating dynamic lift (in direction of car traveling) due the aerodynamic properties of wing profile. Dynamic lift is just another term for pressure difference between front and rear side of moving propeller. Car is basically sucked into lower pressure area in front of the propeller. There might be analogy with DC voltage boosting. We could create higher voltage from low one, but we have to pay by smaller output current. Total amount of power is still preserved. In case of car, we could create higher speed (via pressure difference boost), but we have to pay by smaller front area of vehicle (in compare with equivalent static flat panel). Keep in mind also v^2 in drag equation.

    • Ailsa Ni
      Ailsa Ni

      I see all those comments about the solar sail idea and they all stuck to the problem that unlike wind sails here at eath, in space there is no second medium like ground or wa

  • Liam Murphy
    Liam Murphy

    "Please keep it civil". Dude, this is FIbill. A bit like expecting a sail boat to outpace the wind.

    • Ken Gill
      Ken Gill

      My cat could easily do that on a very broad reach.

  • Rutledge Dufort
    Rutledge Dufort

    The scandalous fruit pathogenetically scatter because church immediately chew off a short bush. bitter, spotless mouse

  • Gear Sub
    Gear Sub

    I have a question, What if this vehicle had a sail like the boat and a propeller at the same time?

    • imd12c4advice

      It would make it slower.

  • Ankit Jana
    Ankit Jana

    I think that the stored angular momentum of the propeller is causing faster than wind speed for some time, eventually the propeller will stop producing thust and it will no longer move faster than wind.

    • eyytee

      Nope, it works in steady state. It cannot use stored energy for propulsion.