actuating pressure a very compact high output automatic parking brake is achieved further because the brake cylinder signal brk is controlled by the locomotive brake system controller 20 like ccb u00ae brake system which provides closed loop pressure control of the brake pressure any undesired main reservoir leakage from the parking control valve 30 to the brake cylinder 10 will be automatically exhausted by the locomotive brake system controller 20 making the system very fault tolerant as further embellishment of the parking brake system for locomotive according to the present invention is illustrated in fig2 when the brake cylinder 10 with parking locking mechanism 14 is installed on a locomotive that is also equipped with the locomotive brake system controller 20 e g a computer controlled brake system then the locomotive brake system controller 20 could be commanded by an electrical switch pbc 40 pbc 40 may be operated by the driver via dotted line 42 to pressurize the brake cylinder to mr pressure or other selected pressure as needed to provide the required parking brake force directly from the brake cylinder relay 22 the parking brake lock pilot pressure could similarly be controlled by the locomotive brake system controller 20 using.