This rotary control system for a device includes a rotary control member, rotationally mobile about a first fixed axis, between first and second positions, and a rotary control handle, intended to be secured in rotation with the rotary member about the first axis. It also includes a blocking device, that can be selectively moved, when the rotary member is in its first position, between a blocking configuration, in which it prevents the movement of the rotary member to its second position, and a release configuration, wherein the movement of the rotary member to its second position. This system further includes a locking plate, rotationally mobile about the first axis relative to the rotary member, when the rotary member is in its first position, between a locking position, in which a first orifice passing through the rotary member is superposed with a second orifice passing through the locking plate.