abstract:Deflected slipstream is an approach to creating an aircraft that can take off and land vertically (VTOL), or at least with a very short runway (STOL). The basic principle is to deflect the slipstream from one or more propellers approximately 90 degrees, to create an upward thrust for vertical takeoff and a downward air cushion for landing.
Groundeffectmachines (hovercraft), convertiplanesoraircraft that hover by means of propeller slipstream (s) deflecteddownward are notconsidered to behelicopters.