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So, did/does the vehicle in the desert start with a push (from a force other than the wind) or did it really get started moving by the wind pushing it?

Edit: FYI in the video he does sort of cover his claim even if it got started by a non wind force by stating the vehicle can maintain a speed faster than the wind pushing it. But I'm still curious, was a non wind force needed in the desert to get it started?



Any wind that's strong enough to overcome static friction would do the trick, and I can't see why 10mph wouldn't be enough.

The small models that you can build at home (sorry, can't find the plans anymore; this was 10 years ago now) do not require a push to get started.


Understandable that it doesn't take much wind for a vehicle well under a pound. But what about one that weighs well over 100 pounds?


In the veratasium video [1] you can see it starting just from the wind (first attempt is around 5:20). It works just fine because as you scale up the vehicle you scale up the propeller, so there's plenty of surface for the wind to push against.

1: https://www.youtube.com/watch?v=jyQwgBAaBag


The 100 pound vehicle also has a much larger cross section to the wind. And its propeller is further off the ground, so it's getting cleaner wind than the little model version.

I can get a boat that weighs more and has less sail area going on less wind than that. And that thing has to be dragged through the water on top of everything else.


In the water, there is no static friction and no velocity-independent friction. If you push a floating boat, it moves.


Fair point. Though, I would guess that Blackbird's internal mechanisms are well-enough engineered that it has very, very little static friction where it counts.


My motorcycle with me on it can weight 700-800 pounds and has a much smaller cross sectional area than blackbird. And yet it still gets pushed around sometimes by crosswinds .


If I understand what you're saying though, you would be in motion on the bike as the crosswind pushes against you- it takes a lot less force to shift your heading while moving forwards than if you were being blown sideways while stationary.

Unless I'm misinterpreting your statement- perhaps you have a hobby of riding in hurricanes, which would be rad. :)


I've definitely ridden through some storms that felt that way!


The fan blades are an airfoil, which have a minimum speed to create the lifting effect.


Lift isn't really a part of how this gets started. Regular old pushing works on airfoils, too.


No, it’s light enough for the wind to start pushing it.


Even with 100+ pounds (50+ kg)?


Yes, at the extreme end you can find videos of 3,000+ lb cars flipped by the wind.

It looks quite aerodynamic, but by comparison I can start pushing a 3,000lb car on flat level ground. So this thing probably needs less than 10 pounds of force to start moving.




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