A coating system for applying coating liquid such as a base coat, a paint, a lacquer or a protective layer to surfaces of buildings, wind turbines, ships and aircraft. The coating system includes an unmanned aerial machine in the form of a helicopter for dispensing the coating liquid. The aerial machine has a fuselage, two rotors, a tank for holding the coating liquid, and an applicator for dispensing the coating liquid and outputting same onto a surface to be coated. In order to supply the tank with coating liquid, the tank is fastened to the aerial vehicle and the tank or aerial vehicle has a filling opening for refilling the tank in the landed state of the vehicle, and/or the tank is part of an exchangeable tank module coupled to the fuselage and/or is uncoupled from the fuselage by a coupling device controlled in an automated manner.