are taught to apply forward cyclic to fly out of the condition and/or lowering collective pitch. While transitioning to forward or lateral flight will alleviate the condition by itself, lowering the collective to reduce the power demand decreases the size of the vortices and reduces the amount of time required to be free of the condition. However, since the condition often occurs near the ground, lowering the collective may not be an option; a loss of altitude will occur proportional to the rate of descent developed before beginning the recovery. In some cases, vortex ring state is encountered and allowed to advance to the point that the pilot may severely lose cyclic authority due to the disrupted airflow. In these cases, the pilot's only recourse may be to enter an autorotation to break the rotor system free of its vortex ring state. Tandem rotor helicopters In a tandem rotor helicopter, forward cyclic will not arrest the rate of descent caused by VRS. In such a helicopter, which utilizes differential collective pitch in order to gain airspeed, lateral cyclic inputs must be made accompanied by pedal inputs in order to slide horizontally out of the vortex ring state's disturbed air. Radio control multirotors Radio controlled multirotors (common on drones) are subject to normal rotorcraft aerodynamics, including vortex ring state. Frame design, size and power affect the likelihood of entering the state and recovering from it. Multirotors that do not have altitude hold are also more likely to succumb to operator error, where the pilot drops the craft too fast resulting in the upwash at the rotor hubs that can lead to vortex ring state. Those that are equipped with that feature, on the other hand, tend to control their descent automatically and can usually (but not always) escape the dangerous condition. See also Aerospace engineering Ground effect (aerodynamics) Helicopter flight controls References External links Vortex ring state FAA Helicopter Flying Handbook Free-Vortex Wake Calculations of Helicopter Rotors and Tilt-Rotors Operating-In and Transitioning Through the Vortex Ring State Dispelling the Myth of the MV-22 Archive Vortex Ring on SKYbrary Vuichard Recovery Technique - How to escape a Vortex Ring State - Video showing recovery technique, and visualisation using water spray. Helicopter aerodynamics Aviation risks Vortices