What am I not understanding here?
How do you go 155 mph unless the wind is blowing 155 mph?
They may be taking advantage of some geography. In a town I used to live in, Spruce Grove, it could be a light breeze from the west. However, Spruce Grove sat in a slight valley which funnelled the wind into a more narrow space and the force of the wind increased.
Maybe something like that
Iceboats have been sailing multiples of the wind speed for over a century. It’s possible because of the lack of friction between the ice and the runner blades.
America’s Cup boats on hydrofoils also sail faster than the wind. A lot of catamarans can do it also.
What the sails on any of the above sense is not the “true” ambient wind, but the “apparent wind” which is the addition of the “true” wind and the vessel’s forward speed. The faster you go, the faster you go....
Rocket Launch
31,393 views Mar 6, 2014
After a 10 year restoration by members of the North Shrewsbury Ice Boat & Yacht Club in Red Bank, NJ, and after nearly a 100 year absence from the ice, the 50ft long ice yacht, the ROCKET is sailed on the Hudson River on March 1, 2014.
https://www.youtube.com/watch?v=dzf-jeKhk4Q&ab_channel=ebrattlof
Sailboats like the America's Cup hydrofoils, iceboats, and the iceboat on wheels land yacht, can all go faster than the prevailing wind by using the sail as a wing. Wind blowing around the the sail produces lift just like an airplane wing, but because the sail sticks straight up, the 'lift' generated pulls the boat forward.
They can only make these high speeds when sailing into a quartering wind.
None of the above can sail faster than the wind going directly downwind.
> How do you go 155 mph unless the wind is blowing 155 mph? <
The wind is a force. When the wind is to your back, it will add to your speed. You will go faster and faster and faster until the wind force is balanced out by other forces. The balancing forces here are road friction and air resistance.
Maybe this will help. Think of the land yacht’s speed as money in the bank. You have nothing in the bank now. You decide to add $10 per day. You have $10 then $20, then $30 etc. That $10 deposit is not a limit. It just adds to what you already have.
Then you sign up for an automatic payment plan that costs $10 per day. Your deposit is now balanced out by a withdrawal. Your savings will no longer increase.
Americas Cup boats are reaching insane speeds now......
My thanks to everyone for their helpful explanations.
So - theoretically - a fully loaded super tanker could go 100 mph on a calm sea, if they could attach enough sail square footage to it?
When Running, you cannot go faster than the wind.