3 HN users recommended this explainer3 months2021–2023score 3
Years with an HN recommendation, 2007–2026
Linked as clear demonstrations that make the counterintuitive faster-than-wind result click.
Veritasium recounts a $10,000 bet with a UCLA physics professor over whether a vehicle can travel downwind faster than the wind. He presents the professor's reasoning and demonstrations, including one without aerodynamics.
“The small demonstration that made it click for me is from that video” (HN, 2021)
Original video triggering the bet for context: [link] Video discussing the bet and going over criticism: [this video] Veritasium is a great YouTube channel.
The small demonstration that made it click for me is from that video: [this video] This is exactly what the blackbird does, only with a propeller pushing air in place of the big wheel, and it's a much clearer and simpler demonstration of the same idea, which you can trivially verify.
Simple demonstration making the downwind faster-than-wind idea click.
Derek from the YouTube channel Veritasium made two interesting videos about this vehicle. [link] [this video] They go into some nice detail about why the physics works out the way it does.
The most surprising thing here is that someone on Twitter made a bet, lost the bet, and then actually paid said bet. Playing devil's advocate here a little: The whole machine is very counter-intuitive, and I can see how I myself may disbelieve it if not for the irrefutable demonstration(s)[0]. [0] [this video]
Irrefutable demonstration of the counterintuitive wind vehicle.
The professor's reasoning is near the start of the video about the bet [1]. Basically they thought the makers of blackbird were fooling themselves (e.g. measuring slower wind at the bottom of the car vs the top of the propeller, or getting pushed above the average wind speed by gusts then selectively reporting). 1: [this video]
Explains the professor's skeptical reasoning about the blackbird.
I doubt this is how sailboats are doing it (if they're doing it) but one way is (I think) to make the airfoil itself cut across the wind while the "boat" goes straight downwind. See these videos: [link] [this video]
Video list and Hacker News comment labels from HackerTube (prompted by @karpathy), released under ODC-By 1.0, built on the open-index/hacker-news archive. Hacker News data is provided by Y Combinator; comments remain the work of their authors. Video titles, channel names and thumbnails belong to their creators and are shown via YouTube. HackerTube Watch is an unofficial edition. Data export of 2026-10-31.
8 Hacker News comments
From the HN archive; up to 20 kept per video, favoring different commenters. Recommendations first.
Citations, criticism and jokes