A flight unit control system having at least one instrumented fastening bolt connecting an aircraft carrier structure and a load path, the instrumented bolt having at least one measurement area for detecting that the load path is under load and including a fastener for locking the instrumented bolt in a position relative to the aircraft carrier structure and load path and wherein the measurement area has two cavities and at least one strain gauge and wherein the fastener includes a plate which is positioned at a threaded end of the instrumented bolt which bears against one of the aircraft carrier structure and the load path and which extends perpendicularly to an axis of the bolt and a nut which is placed at the threaded end of the instrumented bolt to immobilize the instrumented bolt relative to the aircraft structure or the load path.