Wing including an upper surface predominantly concave upwards and a lower surface predominantly convex downwards, which wing is provided with one or more supports to be fixed to a vehicle, in which the lower surface of the wing is provided with one or more slits that connect with the outside one or more first ducts arranged in the wing, which are in turn connected to at least one second duct arranged in at least one support, wherein at least one valve connected to at least one actuator is arranged along the second duct or along a third duct connected to this second duct. A process for controlling the operation of the wing and a motor vehicle includes this wing.