Abstract: A wind tunnel for stable sustained human flight for research or recreation, including a tunnel including first and second portions having first and second central axes, respectively, and a fan to create an air flow in the test section. The second portion is a test section. The first and second central axes are arranged at a first angle with respect to each other. The second central axis is at a second angle of 5°-85° with respect to a horizontal plane. A safety system for an inclined wind tunnel for stable sustained human flight is provided, including an inclined test section of the wind tunnel that is arranged at an angle of 5°-85° with respect to a horizontal plane, a fan to create an air flow in the test section directed from an upstream end towards a downstream end thereof, and a delimiting arrangement arranged at the test section for preventing a person using the test section from leaving it.

Abstract: Device for cleaning crankcase gases from an internal combustion engine by means of a centrifugal separator (14), comprising a housing (16) with a rotor (22), which is rotatably supported in the housing and has a plurality of tightly separated separating discs (20). The housing (16) has an interface surface, which is designed for direct mounting of the housing (16) over a corresponding opening in a valve cover of the internal combustion engine.