Airplanes obviously employ very different engine technology compared to ground vehicles, but some actually do use a form of ...

Then I look at the tip-speed, and extend the diameter of the propeller as far as I can, so that at maximum rpm, the propeller is not going above 850 feet per second on the tip-speed. At about 800 ...

Thus [Valkyrie Workshop] has come up with a simple but ingenious rig to evaluate a motor and propeller combo without ... automobile so it can be tested at speed.

The boat captain can, of course, unlock the blades to allow them to fold when hydrodynamic optimization and speed are prioritized over regeneration. The Hybrid propeller offers a simple ...