Vortex Ring State (aka Settling with Power or the Wobble of Death) is a flight condition common to all rotor aircraft (helicopters and multirotors/quadcopters/drones). For those new to the hobby, they may inaccurately attribute this condition to a fault of their aircraft. But really, it is just a flight phenomenon similar to airplane wing stall. This video discusses its cause, along with demonstrating how to recover from it. More importantly, methods of avoiding it entirely are also discussed and demonstrated.
Other helicopter/multirotor flight phenomenon discussed include: In Ground Effect Hover (IGE), Out of Ground Effect Hover (OGE), and Helicopter Translational Lift.
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