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From Wikipedia: An autogyro (from Greek αὐτός and γύρος, "self-turning"), also known as a gyroplane or gyrocopter, is a type of rotorcraft that uses an unpower
by pcl 7y ago
From Wikipedia:
An autogyro (from Greek αὐτός and γύρος, "self-turning"), also known as a gyroplane or gyrocopter, is a type of rotorcraft that uses an unpowered rotor in free autorotation to develop lift. Forward thrust is provided independently, typically by an engine-driven propeller. While similar to a helicopter rotor in appearance, the autogyro's rotor must have air flowing across the rotor disc to generate rotation, and the air flows upwards through the rotor disc rather than down.
https://en.wikipedia.org/wiki/Autogyro https://en.wikipedia.org/wiki/Autogyro
- ultrarunner 7y agoThe thing that made autogyros (and helicopter autorotations) click in my mind was when someone pointed out that the outside of the rotors is spinning faster than the inside. As such, there's a balance where some point inward of the rotor tips will be driven by air flowing through causing the outside to spin fast enough to generate positive lift. There's obviously more to it, but if anyone is wondering why air going up through a rotor somehow causes that rotor to push air back down, this might be a helpful way to think of it.
- taneq 7y agoHuh, that makes sense. I always wondered about that. It's a little like the related (though different) question of "can you sail downwind faster than the wind is going" (and the answer is yes: https://inhabitat.com/wind-powered-vehicle-travels-faster-than-the-wind/ https://inhabitat.com/wind-powered-vehicle-travels-faster-th... )