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 ISboth 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: isboth.infof... .

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

▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀
References
Jack Goodman's ISboth 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

Ummæli

  1. Veritasium

    Veritasium13 dögum síðan

    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).

  2. Aryan Komati

    Aryan Komati12 dögum síðan

    I'm mind blown

  3. Rick Cavallaro

    Rick Cavallaro12 dögum síðan

    @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. :)

  4. Noguffay

    Noguffay12 dögum síðan

    @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.

  5. Papa Legba

    Papa Legba12 dögum síðan

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

  6. Joeri sol

    Joeri sol12 dögum síðan

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

  7. Aslami Jesorin

    Aslami Jesorin3 klukkustundum síðan

    The plant religion consecutively burn because llama unexpectedly admire off a cowardly taiwan. sticky, shivering shoe

  8. TheFlyingCrud

    TheFlyingCrud3 klukkustundum síðan

    Absolutely genius! I'm proud to say I figured out a decent amount of what was happening here after the fan part was mentioned, but that being said this is so counterintuitive I never would have thought of it in a thousand years. Great work to the team, amazing thought process and execution here. A great example of true ingenuity!

  9. Steve Jorgensen

    Steve Jorgensen4 klukkustundum síðan

    adapt this so you can go faster then the speed of light.

  10. TrasherFCR

    TrasherFCR4 klukkustundum síðan

    16:26 Maybe the tape began to flutter in the other direction, because the propeller tightens the flow of air in this area or just the wind speed temporarily decreased, and the wind car moves by inertia!??

  11. yoursotruly

    yoursotruly4 klukkustundum síðan

    Put one of these on top of your Volvo and you'll break the laws of most states in the union along with some power lines but you'll get to jail faster than the wind.

  12. tkirby115

    tkirby1154 klukkustundum síðan

    I am not going to take an interest in explanations as to how this is anything but a working over-unity device.

  13. David Harrington

    David Harrington4 klukkustundum síðan

    Well well well you did it kool

  14. SansWord Huang

    SansWord Huang4 klukkustundum síðan

    Is there a possible maximum speed with this vehicle? It feels like a Perpetual motion machine if it does not have upper bound speed for given wind speed.

  15. D Harrell

    D Harrell5 klukkustundum síðan

    NOT IMPRESSED, unless you design one that brews coffee!

  16. Matt Montgomery

    Matt Montgomery5 klukkustundum síðan

    I assume there was some gps or speedometer reading to compare with the measured wind speed? I believe that it is possible, but the fan could also suck the ribbon backwards, right?

  17. Sudip Mandal

    Sudip Mandal6 klukkustundum síðan

    @Veritasium Could you please explain what happened between 12:15 and 12:30. You mention in the video too something is wrong, and the string clearly shows wind blowing forward, but the vehicle is not moving forward and the propellor is moving ANTI-CLOCKWISE which should be impossible if its due to the wind. Also you mentioned the propeller is turned by the wheel, this is clearly not what is happening during this time frame, the wheels are not moving at all but the propeller seems to be gaining speed in a direction opposite to the wind direction, this does hint at some kind of internal motor and not wind.

  18. Rick Cavallaro

    Rick Cavallaro5 klukkustundum síðan

    Unlike me, Derek has a life, so I'll take a crack at this... The vehicle has two sets of brakes - a hand brake and a foot brake. But the vehicle weighs 450 lbs without the "pilot". So we like to bring propeller pitch down to zero to do most of the deceleration, and that's pretty effective. Once we're going pretty slow, we use the actual brakes. So this is what we instructed Derek to do - and he did. But it turns out the pitch mechanism has shifted somewhat over the decade since I'd seen the Blackbird. And this had two very unfortunate effects. First the pitch could now go negative rather than bottoming out at zero. Secondly, the pitch was no longer matched between the two blades. This is what caused the awful shaking. So Derek pulled the pitch all the way back, and when he was near a stop, he used the brakes - exactly as we'd suggested. But now he's sitting still with a tailwind and a propeller with negative pitch. Now we have a ratchet that allows the wheels to drive the propeller, but it doesn't allow the propeller to drive the wheels. It will simply let it freewheel. This is there to meet the requirements for the record runs that we cannot use stored energy at any time. >> this does hint at some kind of internal motor and not wind. You can be certain the officials at the North American Land Sailing Association inspected it pretty carefully for that sort of thing prior to the official record runs.

  19. Phil Rossoni

    Phil Rossoni6 klukkustundum síðan

    I've seen this video and understood it before but I find myself having to relearn it again. Nice job reexplaining it!!!

  20. William Potter

    William Potter6 klukkustundum síðan

    In other words; it's a wind-powered air boat, but for land.

  21. Rugg Tomcat

    Rugg Tomcat7 klukkustundum síðan

    Just here for the Scottish commenters when they see 'Joby'

  22. Lydia Hilles

    Lydia Hilles7 klukkustundum síðan

    In all honesty you aren’t necessarily going faster than the wind, you are slowing the wind down creating negative pressure relative to the back therefore “leap frogging” the air current

  23. Rick Cavallaro

    Rick Cavallaro3 klukkustundum síðan

    @Lydia Hilles >> oh did i touch a nerve? Nope. You just said something incorrect and I corrected you.

  24. Lydia Hilles

    Lydia Hilles4 klukkustundum síðan

    @Rick Cavallaro oh did i touch a nerve? I didnt mean to offend you. Just remember friend, you are not your beliefs:)

  25. Rick Cavallaro

    Rick Cavallaro5 klukkustundum síðan

    In all honesty we have a world record for going directly downwind at 2.8X wind speed steady-state, and another for going directly upwind at 2.1X wind speed steady-state.

  26. Lydia Hilles

    Lydia Hilles7 klukkustundum síðan

    This time on primitive wheels, we will try to break the speed of wind!

  27. cuandotubetube

    cuandotubetube7 klukkustundum síðan

    The wind speed is greater than the height of the propeller ;) .

  28. no body

    no body7 klukkustundum síðan

    wow wow wow whait what ? if this concept works with solar wind that would be pretty cool ?

  29. Bradley

    Bradley7 klukkustundum síðan

    veritasium, ive always had this question in mind. why is your eyes always slightly pink or red every time you film, is it genetics?

  30. Maypep Necro

    Maypep Necro8 klukkustundum síðan

    13:33 This is when he is risking his life. Thanks me later.

  31. Dangerous One

    Dangerous One8 klukkustundum síðan

    This was the most fascinating experiment since the airplane on a treadmill.

  32. Dangerous One

    Dangerous One8 klukkustundum síðan

    So can this be put on a boat and get similar results? Future of sailing?

  33. David Phillips

    David Phillips8 klukkustundum síðan

    Dude, you behaved so timidly during this that it makes me embarrassed for you. Have some balls, man.

  34. Redswap

    Redswap4 klukkustundum síðan

    @David Phillips 1) He wasn't going to cry. You can't tell he was going to cry. In fact, I don't expect a normal person to be crying while being afraid of something. Usually children do that, not adults. 2) I don't think fear is always a bad thing and I don't think people should be socially pressured against it like you do. 3) I personally don't think he was more scared than any average person. What he's doing in life has nothing to do with fear, so I guess anybody would have had a similar reaction, or even wouldn't want to go in the vehicle. You can't generalize your personal emotional states to everyone, everybody is different. If you want to prove something, use a valid logical proof or go get or make a scientific experiment.

  35. David Phillips

    David Phillips5 klukkustundum síðan

    @Redswap This guy hesitated at the slightest hint of any risk. It’s pretty pathetic. I definitely didn’t do that when I was in Afghanistan looking for IEDs and scanning for ambushes. he looked like he was going to cry at the slightest deviation, that’s honestly the perfect indicator for this weak ass generation. I bet this dude would literally piss himself if he heard the supersonic crack of an incoming round.

  36. Redswap

    Redswap6 klukkustundum síðan

    wtf

  37. Md Sumon

    Md Sumon8 klukkustundum síðan

    The utopian gosling suggestively blink because hyacinth consecutively decay toward a highfalutin thunderstorm. sticky, uninterested month

  38. Gary Y

    Gary Y8 klukkustundum síðan

    So when you got faster then the wind, you are against wind, you would go back?!

  39. Gianluca Lepri

    Gianluca Lepri8 klukkustundum síðan

    We have to measure if a wind moving vehicle can go faster than the air. Why don't se put a tape in front of the fan? .. GREAT JOB ✌️

  40. Ken North

    Ken North8 klukkustundum síðan

    I imagine this would not work if the propeller was at the same elevation/plane as the body of the car, is that correct?

  41. John Borton

    John Borton8 klukkustundum síðan

    You could lower the prop by a couple feet is all and still clear the chassis. It would still work fine. We left this room on the chassis in case we needed to install a bigger prop.

  42. Amanuel Amente

    Amanuel Amente8 klukkustundum síðan

    If the proper can take some energy from the wind behind and convert it into kinetic energy, please do the same in a still weather condition. What difference would it make than conducting the experiment down the wind. Your machine should get moving. Right? And hence perpetual.

  43. subductionzone

    subductionzone6 klukkustundum síðan

    It is not perpetual motion. Nor does it take energy from the wind "behind". What it does is to lower the speed of the air that it interacts with relative to the ground. When it is going faster than the wind it is lowering the speed of the air in front of it relative to the ground. The energy from that wind goes into the cart. If the wind is not blowing there is no energy to be removed from it.

  44. Mach Fiver

    Mach Fiver9 klukkustundum síðan

    Did that look scary because it didn't feel too bad... insert Beeeeepeeeeeeeep flatline Jacobs ladder analogy

  45. Mach Fiver

    Mach Fiver9 klukkustundum síðan

    Oh what with the windsock backwards who now

  46. Mach Fiver

    Mach Fiver9 klukkustundum síðan

    Nearly a guaranteed chance for success. Here you drive now it's windier than before and don't worry about it lopping off your head...ish

  47. Claude Desaulniers

    Claude Desaulniers9 klukkustundum síðan

    This is dumb. No he did not travel faster than the wind. The only reason the ribbon went backwards is because the breeze stopped blowing and the cart still had momentum.

  48. John Borton

    John Borton5 klukkustundum síðan

    @subductionzone Yep -- that's why we built it to crush. When you beat the wind by 1.1, it leaves you open for all sorts of explanations that are not rationally there at 3x. They're still there of course ... just no longer rational. :)

  49. subductionzone

    subductionzone6 klukkustundum síðan

    Derek is not a skilled driver yet. The guy holding the windsock built it and piloted it during its record setting run. It was going 2.8 times the speed of the wind then Derek did get it up to just past the speed of the wind. And there are other videos of the cart. In one it has four different streamers. One is at a height above the prop. Outside of its area of influence and at a height where the ground has not slowed the wind. It is still faster than the wind.

  50. Claude Desaulniers

    Claude Desaulniers8 klukkustundum síðan

    @Deputy Dog Yes, I did see the windsock. The wind was blowing the windsock at maybe 3-4 miles per hour, but the cart was still rolling with momentum at between 5-8 miles per hour, hence the ribbon going backwards.

  51. Deputy Dog

    Deputy Dog9 klukkustundum síðan

    You did see the windsock, didn't you?

  52. Mach Fiver

    Mach Fiver9 klukkustundum síðan

    A little unbalanced that harmonic looks sketchy as hell unless lopping off your head helps to reduce the drag coefficient.

  53. Claude Desaulniers

    Claude Desaulniers9 klukkustundum síðan

    I'm glad he thinks that ten miles per hour is intense !

  54. Mach Fiver

    Mach Fiver9 klukkustundum síðan

    But it's transfering windspeed through gears to increase its speed faster than the winds speed. I fail to see how the conservation of energy law is broken. The spinning blades energy is being used to spin gears to multiply the input. Perpetual motion I thought refers to a single input to achieve an infinite output. The blades are getting a continuous input. Does it slow to a halt if the wind dies?

  55. John Borton

    John Borton9 klukkustundum síðan

    No laws (of physics) were broken in the making of this video. It stops when the wind stops.

  56. Strong Kiteboarding

    Strong Kiteboarding9 klukkustundum síðan

    Kiteboarders can go faster straight downwind than the wind. I have done it myself.

  57. Strong Kiteboarding

    Strong Kiteboarding3 klukkustundum síðan

    @subductionzone I have not seen it laid out in a video like this but it is nothing new and commonplace in the sport. The kite moves in a sine or circular motion and produces lift. That coupled with the board speed will accelerate faster than the wind. Same principle as in the video but on lines and swinging rather than spinning on a shaft.

  58. subductionzone

    subductionzone4 klukkustundum síðan

    @Strong Kiteboarding Do you have a link supporting your claim?

  59. Strong Kiteboarding

    Strong Kiteboarding4 klukkustundum síðan

    @subductionzone well with a bit of research you will see yes, directly downwind. On a foil board and while moving the kite up and down. It is a similar principle to the video. Most competent foil riding kiteboarders can do it, nothing magical going on.

  60. Rick Cavallaro

    Rick Cavallaro5 klukkustundum síðan

    I've been kitesurfing for 20 years, and I can tell you for sure that the only way to go directly downwind faster than the wind kitesurfing is to build up a lot of speed and then turn downwind. For a matter of seconds you can go directly downwind faster than the wind - and then re-launch your kite.

  61. subductionzone

    subductionzone6 klukkustundum síðan

    On a VMG, yes. But directly downwind, no. But if you think that you have you should contact NALSA and have them verify your claim. You will have your own world record if you do so.

  62. Eric Godfrey

    Eric Godfrey9 klukkustundum síðan

    This feels like a 10 minute video stretched out, with unnecessary drama, to reach 22 minutes. The length of a 30 minute tv show with ad spots. Is he pitching for a tv gig?

  63. Luis Ribeiro

    Luis Ribeiro9 klukkustundum síðan

    Love the video, not the clickbait title tho tbf

  64. Added value applications

    Added value applications10 klukkustundum síðan

    when the wind blows it is slowed down by friction with the ground. ie wind speed increases with height. In aviation circles this is known as wind gradient. The top part of the air screw is experiencing much higher wind speed than that measured at ground level... good trick though

  65. subductionzone

    subductionzone6 klukkustundum síðan

    It has been shown to go faster than the wind by taking that into account as well. Derek may not have gone faster than the wind, but that backwards pointing streamer is pretty strong so I would say that you are wrong. Do you know how they could test your claim with streamers?

  66. Lefty Holmes

    Lefty Holmes10 klukkustundum síðan

    New Experiment: Build an Electric Motor that generates its own power !!!

  67. Shly Hoit

    Shly Hoit10 klukkustundum síðan

    I think it's the spinning fan blade generating some negative pressure on the other side and that negative pressure causes the fan to spin slightly faster.

  68. jeff kane

    jeff kane10 klukkustundum síðan

    Warp drive, powered by push back. Scotty and I LOVE it.

  69. soulreaver 555

    soulreaver 55510 klukkustundum síðan

    The future of travel!

  70. Jaka Sulthon Hidayah

    Jaka Sulthon Hidayah10 klukkustundum síðan

    In my imagination : can LASER-powered vehicles moves faster than the LASER speed itself?

  71. Jeff Blakeman

    Jeff Blakeman10 klukkustundum síðan

    The vehicle looked like it was designed to minimize drag. How did the air push it from the start instead of just flowing around it? Could a boat be built this same way, with a propeller in the water driving a fan in the air?

  72. Rick Cavallaro

    Rick Cavallaro5 klukkustundum síðan

    From a dead stop the wind acts mostly on the propeller blades. But you're right that it's not very effective. A boat could be built the same way. It would probably have to be a foiling boat to beat the wind speed.

  73. András Lőrincz

    András Lőrincz11 klukkustundum síðan

    "Risking my life" At what point of the video? Seriously...

  74. Rick Cavallaro

    Rick Cavallaro5 klukkustundum síðan

    Probably the point where 200 lbs worth of pylons, nacelle, and spinning blades were threatening to come down on the driver. The whole thing folds forward for travel.

  75. Jonathan Maglasang

    Jonathan Maglasang11 klukkustundum síðan

    It's really not violating any physics law if we consider that the wind speed profile is different near the ground and at the propeller height. The wind speed at the propeller height is much higher than the wind speed at the speed indicator. This is just another D'Alembert's Paradox that needs Prandtl's boundary layer theory.

  76. subductionzone

    subductionzone6 klukkustundum síðan

    Nope.

  77. I reckon I can build that

    I reckon I can build that11 klukkustundum síðan

    The two sail boat explanation doesn't account for the driven wheels

  78. eyytee

    eyytee10 klukkustundum síðan

    I doesn't mention it explicitly, but the boats have keels, which force the sail to move across the wind. Just like the wheels & transmission force the propeller blades to move across the wind.

  79. Rocky Mountain Lockpicker

    Rocky Mountain Lockpicker11 klukkustundum síðan

    Really cool video!

  80. Snowjix

    Snowjix11 klukkustundum síðan

    This feels like a bunch of americans (and an ozzy) just having fun in a massive backyard, i love it.

  81. sindri177 sindri177

    sindri177 sindri17711 klukkustundum síðan

    Love how he changes to kph at the end, but with the group they used mph

  82. Rush Bayou

    Rush Bayou11 klukkustundum síðan

    the first step to discovery is to overcome dogma...

  83. Rush Bayou

    Rush Bayou11 klukkustundum síðan

    wonder... at the moment the wind no longer wrks as a driving force vs the wings driving force takes over, if this moment it could result in a stall. and or ... how much drag the wind now creates? id luv to see a precision build vehicle for this application and if one could be build for water also. could u imagine the speeds u could get? one day the conversation will be " can we break the sound barrier with this drive method?" . :) just saying . how many other forms of energy can have a similar breakthrough? ive always thought magnets could.

  84. Graye Wasden

    Graye Wasden11 klukkustundum síðan

    Question: if the wheels were bigger aka higher angular velocity would that increase the wind multiplier??

  85. Rick Cavallaro

    Rick Cavallaro5 klukkustundum síðan

    If we had bigger wheels, without changing the propeller pitch or gearing, it would reduce what I call the "vehicle speed ratio". It could still go faster than the wind, but by a smaller multiple and with more torque (which is to say it could climb a steeper hill while going at exactly wind speed).

  86. Chris Webber

    Chris Webber12 klukkustundum síðan

    It makes complete sense...not sure what the debate can even be. But so what? What does this prove? Its not perpetual energy because energy is being consumed at a rate quicker than its being "replenished" The theory is still the same and still stands.

  87. Master of none

    Master of none12 klukkustundum síðan

    The only thing missing was land survey equipment to show truly flat ground.

  88. Master of none

    Master of none11 klukkustundum síðan

    @Rick Cavallaro nice, very cool!

  89. Rick Cavallaro

    Rick Cavallaro11 klukkustundum síðan

    When we set the record in 2010 we did survey the dry lake bed with some very expensive carrier-phase GPS equipment that had a 2 cm resolution. I think those results are in our submission document (which you can still find on-line at NALSA.org)

  90. CryhmeTime

    CryhmeTime12 klukkustundum síðan

    The german in me: "Should we place a big rotor that could behead you over our heads?"

  91. John Borton

    John Borton8 klukkustundum síðan

    @CryhmeTime Yes you could, but for best efficiency, the drive sprocket of the prop shaft need be directly over the drive axle. Rotating 180 and maintaining this constraint cantilevers the entire nacelle behind the back axle, dramatically screwing with the fore/aft balance of the vehicle.

  92. CryhmeTime

    CryhmeTime9 klukkustundum síðan

    @John Borton Would it not be possible to rotate the rotor tower like 180°? That way it would have to fall around the tower itself before it can hurt anyone. Not perfect but at least it would not be above the head :) Also thanks for the video, had quite fun watching it.

  93. John Borton

    John Borton12 klukkustundum síðan

    When Rick and I designed the craft, we had much discussion about the driver position just for this reason. I argued for the 'hang glider' position which put the drivers head that much farther ahead of the prop. Rick argued for the "F1" position because he didn't want to make a loooong vehicle even longer. His reasons were compelling so when he won I said "Ok, you drive". That literally is how it ended up that he was ensured being the pilot during the records. I never drove it once - never wanted my head that close to blades we built out of windsurfer masts.

  94. QuantumShor

    QuantumShor12 klukkustundum síðan

    Why not have a sail that opens up to catch more wind to get the craft moving, and then close up the sail as you reach past starting speed where the propellor's thrust will take over?

  95. QuantumShor

    QuantumShor6 klukkustundum síðan

    @John Borton I see, Thanks! This prototype on the treadmill reminded me of the physics conundrum with a plane taking off on a treadmill or icy runway where whatever ground speed the plane travels, the treadmill pushes it back in the opposite direction, so does the plane get lift at zero landspeed. Obviously its a different problem set since here the landspeed actually drives the propellor, but people vehemently argue it on both sides all the same!

  96. John Borton

    John Borton12 klukkustundum síðan

    @QuantumShor Perhaps you are right on clearing confusion, but placing the propeller at the rear of the prop shaft complicated vehicle design. There is significant mechanism in the nacelle related to the variable pitch propeller, etc. and overall it was just simpler to place it on the front.

  97. John Borton

    John Borton12 klukkustundum síðan

    We considered a retractable sail, but in the end it didn't make it go faster -- only get up to speed quicker so the idea was abandoned. The vehicle was built only to satisfy one criteria -- set a record over 2x windspeed.

  98. QuantumShor

    QuantumShor12 klukkustundum síðan

    Also, I think half of people's confusion is purely because the propellor is facing in the forward direction, so their mind translates that to it catching the wind and pulling the craft forward. If you put the propellor "facing" rearward, like a submarine, people might intuitively understand it better? Not sure how much the airflow around the wing sticking up impacts the propellor..

  99. skrewy lewy

    skrewy lewy13 klukkustundum síðan

    of course it went faster the blades acted like the hands of a parkour person grabbing and throwing its self forward the wind becomes a stationary object at x amount of speed

  100. Ian Waugh

    Ian Waugh13 klukkustundum síðan

    Amazing! I still don't understand the science but is there a practical application?

  101. Danny Mckenzie

    Danny Mckenzie13 klukkustundum síðan

    Anyone who says "i am not a stupid person" is neither human or a scientist.

  102. Reade Selle

    Reade Selle11 klukkustundum síðan

    Knowing how much you are typically able to understand is human. Admitting, when given a good explanation and demonstration that you were wrong is better.

  103. Jordan Porter

    Jordan Porter13 klukkustundum síðan

    This is a cool topic but this whole “risked my life” thing is wildly over dramatic.

  104. JASTEG SINGH

    JASTEG SINGH13 klukkustundum síðan

    Here is a query can we expect quantised parameters (like energy levels ,spin etc.) of an object to be affected by it's position around large masses (In general can we expect an objects quantumn properties to show a change as it changes it's position around a large mass) Can you help me settle this query

  105. Paul McIntosh

    Paul McIntosh13 klukkustundum síðan

    If it can go faster than the wind, why can't it work with no wind?

  106. eyytee

    eyytee10 klukkustundum síðan

    "why can't it work with no wind?" See the pinned comment at the end.

  107. coolaun

    coolaun10 klukkustundum síðan

    @Paul McIntosh Precisely: it isn't a perpetual motion machine and it needs the motion of the air relative to the Earth in order to work.

  108. Paul McIntosh

    Paul McIntosh11 klukkustundum síðan

    @coolaun Wind is a relative term, relative to the earth. If it were truly a perpetual energy machine, you could give it a push to get it going and it would sustain the speed.

  109. coolaun

    coolaun12 klukkustundum síðan

    Because it needs wind to go faster than. It will accelerate to a multiple of wind speed. If wind speed is zero, any multiple of wind speed is also zero.

  110. Vincent Washum

    Vincent Washum13 klukkustundum síðan

    Is this episode 72?

  111. Schrauber Hugo

    Schrauber Hugo14 klukkustundum síðan

    *Easy explanation:* Power = Force * Velocity . In Perspective of the vehicle, the ground below is always moving faster than the air, because of the wind. Because of that, the wheels can produce more power than the propeller needs to create the same amount of force as the drag of the wheels.

  112. wouterdobbelaere

    wouterdobbelaere11 klukkustundum síðan

    @coolaun that should be fun!

  113. coolaun

    coolaun12 klukkustundum síðan

    Succinct and correct. So simple that even a certain physics professor at UCLA doesn't accept it: he now has a 10,000 dollar bet on with Veritasium. Look on Twitter!

  114. Schrauber Hugo

    Schrauber Hugo14 klukkustundum síðan

    As an engineering student, i did the math and calculated the amounts of energy flows and indeed: you could, if air and gear friction were low enough, accelerate (!) *without speed limit.* (It works going upwind aswell)

  115. Microunit Studios

    Microunit Studios14 klukkustundum síðan

    I am a cylindrical earther as well now. Flat earthers have it all wrong. The earth is a cylinder and the ice caps are the ends :)

  116. Tchelaum Viaja

    Tchelaum Viaja14 klukkustundum síðan

    rewatching the video looking at the pink telltale made me understand it

  117. mushy

    mushy14 klukkustundum síðan

    What I've never understood is in a car driving 80mph, how can a bug inside in car just fly around without it just slamming into the back window? They aren't on a seat having the car move them. Also is the bug technically now flying 80mph + its speed

  118. Freshwaterboy

    Freshwaterboy12 klukkustundum síðan

    @mushy The bug is moving at 80 mph relative to the ground and hovering or only going 1 mph relative to the interior of the car containing the air. Acceleration is relative. Again think of a fish in a tank of water going 80 mph the fish can move through the water, or hover in it even though the entire tank is moving.

  119. mushy

    mushy12 klukkustundum síðan

    @Freshwaterboy so is the bug flying 80mph + its speed if you could radar through the window to the bug

  120. Freshwaterboy

    Freshwaterboy12 klukkustundum síðan

    The air mass the bug flies in is also going 80 MPH. Think of the air in the car as water. You wouldn't expect a fish to fly to the rear of its tank under acceleration but you would expect the water to move. This is why a suspended balloon would move forward in a car under acceleration and backwards under braking.

  121. joseph

    joseph14 klukkustundum síðan

    ​@UCfipmtMPL78YvbJw0YWKFkw Sorry rick but it's not, sorry for my english i am not native english speaker. The experience of the treadmill shows that the energy is brought by it. this turns the propeller and generates an air flow (like a fan) which pushes the cart. the air around the cart does not move because it does not move in relation to the room either (in the room the treadmill does not move and neither does the cart on the treadmill). so this experience is biased. But the system works, why? because the propellers act like a wind turbine with a headwind. @Veritasium Calculations are bad, you have to understand where the energy comes from before doing the calculation. then a mathematical model is made which makes it possible to evaluate the response of the system to the force in play (the headwind vs the resistance of the cart). it is easy to understand that the system gets carried away (like a wind turbine) if the head wind is too powerful (high vehicle speed). Once the point of equilibrium has been found, we switch to a reduced model (on a roller in a wind tunnel) to determine the operating points. It takes a lot more rigor in the project to make it evolve (personally I find it dangerous to move with an unstable mechanical system)

  122. Rick Cavallaro

    Rick Cavallaro10 klukkustundum síðan

    @joseph Certainly. The vehicle exploits the energy of the wind relative to the ground (rather than the wind relative to the vehicle). That's why the propeller and wheels need to be geared to one another. The vehicle leaves a wake of wind that has been slowed down.

  123. joseph

    joseph10 klukkustundum síðan

    @Rick Cavallaro Ok could you explain to me where the energy of the system comes from?

  124. Rick Cavallaro

    Rick Cavallaro11 klukkustundum síðan

    >> the propellers act like a wind turbine No - it does not.

  125. RalphGuiterrez

    RalphGuiterrez14 klukkustundum síðan

    Beautiful man! You guys are the next Wright Brothers! Thank you! Peace, man.

  126. Astrobrant2

    Astrobrant215 klukkustundum síðan

    It's all based on whether the wheels can drive the propeller enough to keep it moving. They can't. You could test this by simply pushing the vehicle and seeing what happens. The wind factor is a diversion. Going downwind only means that there is much less air resistance to the vehicle, so you can get the effect of speeding up -- temporarily. Other effects, like ground resistance will slow the vehicle down to wind speed and below. Will it keep on going? Yes, as long as the wind is blowing. When the wind stops, the car will soon stop. The wind is a constant source of energy, so this isn't a perpetual motion machine and doesn't violate physical laws any more than a sailboat does when it tacks.

  127. Rick Cavallaro

    Rick Cavallaro11 klukkustundum síðan

    I don't see a question in there, so I can't answer it. I do see this statement... "It's all based on whether the wheels can drive the propeller enough to keep it moving. They can't." And it's wrong.

  128. eyytee

    eyytee14 klukkustundum síðan

    @Astrobrant2 'I said "air resistance"' And I said "propeller thrust". The thrust of the propeller is affected by the amount of the relative headwind, and thus by the amount of true tailwind. That's why it doesn't work without true wind. But with a true tailwind, it can go faster than the true wind, in steady state, not just temporarily.

  129. Astrobrant2

    Astrobrant214 klukkustundum síðan

    @eyytee That's exactly what I meant. I said "air resistance" not "air pressure". IOW, the "relative headwind".

  130. eyytee

    eyytee14 klukkustundum síðan

    " Going downwind only means that there is much less air resistance to the vehicle" Not only. It also reduces the relative headwind, and thus increases the thrust the propeller can produce with the same power from the wheels. See the pinned comment.

  131. Azel Short

    Azel Short15 klukkustundum síðan

    Very interesting...

  132. Collin Stifflemire

    Collin Stifflemire15 klukkustundum síðan

    He look so stoned sitting in ole black bird

  133. Tcid EH

    Tcid EH15 klukkustundum síðan

    Why Are You Booing Me I’m Right! Personified

  134. Danika Mamie

    Danika Mamie15 klukkustundum síðan

    The lethal dollar strangely number because decimal thankfully balance unlike a lamentable whiskey. tender tense, bloody olive

  135. Anthonie Du Toit

    Anthonie Du Toit15 klukkustundum síðan

    And off course the "obvious solution" to the problem would be to imagine the earth as a cylinder and two sail boats as a prop!? Whooooooosh

  136. J Modified

    J Modified13 klukkustundum síðan

    You don't need that though. You could have the sailboat tack while sliding on a rail attached to a huge floating frame. The whole system could then outrace the wind while going straight downwind. Or, if you insist that the center of mass go straight downwind, do the same with two sailboats that cross each other on two separate rails. Of course this is not possible due to the strength and stiffness of materials you would need, but as a thought experiment it works.

  137. My Biologie

    My Biologie16 klukkustundum síðan

    Nice

  138. Timothy Rogers

    Timothy Rogers16 klukkustundum síðan

    The damaging linen phylogenetically boast because witch karyologically imagine outside a tender tense george. finicky, dusty workshop

  139. Kaleb Bruck

    Kaleb Bruck16 klukkustundum síðan

    But they didn't take one thing into account: aerodynamics

  140. Rick Cavallaro

    Rick Cavallaro11 klukkustundum síðan

    Yeah - we completely forgot to consider aerodynamics when designing the propeller and aerodynamic structures. What were we thinking!?

  141. Avry Wilson

    Avry Wilson16 klukkustundum síðan

    This video is a major fail. The amount of deceit is stunning, not to mention misunderstanding and misappropriation of physics by the channel host. A common theme for all his videos. We need a channel to counter his 'flashy' obfuscation of his pseudoscience. This video has so many fails. And they are explained with very basic arguments.

  142. Rick Cavallaro

    Rick Cavallaro3 klukkustundum síðan

    ​@Avry Wilson >> And you’d rather I sift through 30,000 posts to find it No. I don't care what you do. >> Normally, those who are adamant about defending something are quick to provide info. Once again - I'm not here to defend anything. >> Your roadblocks will not deter me. There's a BIG difference between a roadblock and me not doing YOUR homework. >> I am willing to alter my conclusion... Have at it! And you need not notify me as to whether or not you did.

  143. Avry Wilson

    Avry Wilson4 klukkustundum síðan

    ​@Rick Cavallaro Rick wrote, “Yeah - it's really odd that I would take offense at being called a liar and a fraud.” I’d ask you to quote where I called you a liar and a fraud, but it is clearly unnecessary, isn’t it Mr Cavallaro? I said no such thing, and in galactic contrast all I said was I disagree with your claim. Your insinuation is disgusting. >> This is not how individuals defend a claim, especially in scientific terms/circles. Rick responded, “Of course not! I'm not here to defend a claim, and most certainly not to you.” I will take note of your refusal to defend your claim, regardless of who questions it. Rick wrote, “And you might take note that most people don't consider youtube videos to be peer reviewed scientific journals.” Which is a major problem. Do you not appreciate why that is? Rick wrote, “No one is obligated to provide you with anything.” If you make a public claim, you _are_ obligated. That’s science. If you don’t think you need to, then we can all see where you stand on being open and forthcoming in proving your claim. Your statement is also a standard quip employed in the realm of pseudoscience. >> Will you share your data, design and citations or not? Rick responded, “I have shared all of that many time - right here in these very comments.” Sigh. And you’d rather I sift through 30,000 posts to find it rather be helpful in defending your claim. Normally, those who are adamant about defending something are quick to provide info. Makes for a faster rebuttal, don’t you think? Rick wrote, “It's all available on-line with very easy Google searches.” No they aren’t. I looked. Even went through your old defunct website. The complete design specs for Blackbird don’t seem to exist for consumption. I’d even sign an NDA if you’d care to direct me to the files/data. Rick wrote, “Will I post them here for you? Nope. We've got two world records and the vast majority of people accept the reality of this. I'll have to just figure out how to sleep at night knowing that some random youtube commenter doesn't believe me.” So much for openness to defend something you have so much invested in. And implying I must be wrong by the simple virtue of me being a poster is intrusively bizarre. Cut to the chase, Rick. You don’t want to share because you feel insulted - principles of scientific integrity be damned. And again, I don’t care if a ‘vast majority’ of people accept your version. Popularity is not what decides science. Is THAT what you think? Shall we vote on whether or not gravity exists? Your roadblocks will not deter me. Before I go, I need to say this again: I am willing to alter my conclusion if I have full disclosure of the data, the models, the citations, in that they show I am wrong. The honest thing for you would be to reciprocate. Or is being wrong too scary?

  144. Rick Cavallaro

    Rick Cavallaro5 klukkustundum síðan

    @Avry Wilson >> That you don't like the perceived tone is indeed unfortunate. Yeah - it's really odd that I would take offense at being called a liar and a fraud. >> This is not how individuals defend a claim, especially in scientific terms/circles. Of course not! I'm not here to defend a claim, and most certainly not to you. And you might take note that most people don't consider youtube videos to be peer reviewed scientific journals. No one is obligated to provide you with anything. >> Will you share your data, design and citations or not? I have shared all of that many time - right here in these very comments. It's all available on-line with very easy Google searches. Will I post them here for you? Nope. We've got two world records and the vast majority of people accept the reality of this. I'll have to just figure out how to sleep at night knowing that some random youtube commenter doesn't believe me.

  145. Avry Wilson

    Avry Wilson8 klukkustundum síðan

    @Rick Cavallaro That you don't like the perceived tone is indeed unfortunate. If you feel you've been insulted, it is interesting you employ it as a reason not to participate further. I made a statement about how your claim is wrong based on how it is stated. Why are you not addressing it? I asked you questions about Blackbird. Why are you refusing to answer? I asked for citations, which neither you nor John provided. This is not how individuals defend a claim, especially in scientific terms/circles. You choose to focus on the feelings of our discussion rather than the content. This is indeed telling. I would also like to see the complete design of the Blackbird in order to properly and respectfully assess how the experiment gels with the claim. As I noted earlier, I am open to re-stating my position if the claim is presented in a more concise manner that accounts for certain restrictions in the experiment. Moreover, it apparently needs to be noted that my negative digressions are directed at Derek for his video presentation. Will you share your data, design and citations or not? (Edited to add: I've reviewed my posts in this thread and see no insults inserted by me, and certainly nothing rising to any level of disrespect, much less whimsical or inappropriate.)

  146. Rick Cavallaro

    Rick Cavallaro9 klukkustundum síðan

    @Avry Wilson >> Maybe the volume of disagreements has put a chip on your shoulder. Nope. Your unfounded insults have done that. Good luck with being wrong.

  147. Traffic Cone

    Traffic Cone17 klukkustundum síðan

    This hurts my brain....

  148. Solo5MiiLy

    Solo5MiiLy17 klukkustundum síðan

    this is cool, I learned something new today nc tqsm

  149. beesh2180

    beesh218017 klukkustundum síðan

    I would like to see the airflows at the back of the vehicle. Perhaps there is some kind of acceleration of wind speeds being channelled around the prop's thrust, and the vehicle gets it's extra speed from that?

  150. Glenn Dewitt

    Glenn Dewitt17 klukkustundum síðan

    very interesting...i would imagine drag being one of the major factors in the make or break of this proof of concept. good work!

  151. thelexkex

    thelexkex17 klukkustundum síðan

    this is all BS, we need formulas

  152. thelexkex

    thelexkex16 klukkustundum síðan

    @Rick Cavallaro something i've learned recently is that people who make generalizations can't understand sarcasm

  153. Rick Cavallaro

    Rick Cavallaro17 klukkustundum síðan

    Something I've come to learn for sure about this. The same people that say "this is BS, we need formulas" are the ones that when you give them formulas they say "this is BS, we need to see physical proof!"

  154. eyytee

    eyytee17 klukkustundum síðan

    Google for: "2013 US Team Semifinal Exam - American Association of Physics Teachers" (page 10) "Gaunaa, M., Øye, S., & Mikkelsen, R. F. (2009). Theory and design of flow driven vehicles using rotors for energy conversion." "Mark Drela Dead-Downwind Faster Than The Wind (DDWFTTW) Analysis"

  155. Expired Lamb

    Expired Lamb17 klukkustundum síðan

    Could you do the thing with sails with a solar sails too? Ok, on a serious note: The explainations in this video were amazing!

  156. Nakul

    Nakul17 klukkustundum síðan

    Dude the propeller on the small model at the end of video 18:50 is spinning opposite to how it should, meaning the trailing edge of the propeller is spinning first instead of leading edge which is the fatter side of the propeller, in short you have mounted the propeller incorrectly, the numbers on the propeller should be pointing forward towards the front wheels.

  157. Shato Nyruami

    Shato Nyruami17 klukkustundum síðan

    Why didn´t they let you drive? Isn´t a ISbothr way more expendable than a physicist?

  158. Hhfhgfghg Fghfggg

    Hhfhgfghg Fghfggg17 klukkustundum síðan

    Похожа на спираль закручивающейся и движущейся навстречу потоку воды

  159. atuk brontok

    atuk brontok17 klukkustundum síðan

    i dont know what is what but, yes..

  160. Danteyo aroon

    Danteyo aroon17 klukkustundum síðan

    Where wind speed is lower, Presure is higher, so it is pushed forward by Preasure. Like airplanes pushed up by preasure on wings, basics of fluidodinamic.

  161. DJW1959Aus

    DJW1959Aus18 klukkustundum síðan

    Surprisingly I can intuit this: I can see it and I know it works. They need to build a better structure for that vehicle though!