Ted Ciamillo plans to cross the atlantic this summer in this wet-type submarine in 50 days. The is sub is human (pedal) powered with carbon fiber flukes. Apparently this fun fin (available for humans as the Lunocet) is 15% more efficient than the best rigid propellors! I’m lazy, so I’d love to put a fin like this on an electric boat.
Check out the whole article at New Scientist
Here’s the Lunocet getting close to allowing breach.