Wind turbine blades comprising one or more deformable trailing edge sections, each deformable trailing edge section comprising a first and a second actuator, wherein the second actuator is arranged substantially downstream from the first actuator, and wherein the first actuator is of a first type and wherein the second actuator is of a second type, the second type being different from the first type. The application further relates to wind turbines comprising such blades and methods of operating a wind turbine comprising one or more of such blades.