Autogyros have been around since the 1920’s yet have never progressed beyond the experimental stage except for a WWII Japanese prototype that was said to have been used as a submarine hunter.
And then there was “Little Nellie”, the world’s only attack autogyro, in “You Only Live Twice” of 007 fame.
Interesting, though. Also the Benson Gyrocopter which converted an aluminum skiff into a towed autogyro. One of those Popular Science boats of the future, soon to be within reach of all.
Actually I think Mitt had one patrolling the 2002 Olympics.