The Bell was used in the US Navy, and FAA and NASA V/STOL research projects. The propellers are designed so they can do vertical takeoffs. Instead of the propellers facing forward, they face towards the sky.
We recently posted Koker Iran’s VTOL UA offering. Daily I am seeing stories claiming it to be a worlds first in class. When I first saw it I knew it was something I had seen before but just could not think where. It had stuck in my mind because it loo