Батыс Жолының Автовагондары: Булокомотивпен Жұмыс Істеу Тәсілі

A type of coach used on the Great Western Railway

The GWR autocoach (or auto trailer) is a type of coach that was used by the Great Western Railway for push pull trains powered by a steam locomotive. The distinguishing design feature of an autocoach is the driving cab at one end, allowing the driver to control the train without needing to be located in the cab of the steam locomotive. This eliminates the need to run the engine round to the other end of the coach at the end of each journey. When one or more autocoaches are connected to a suitably equipped steam locomotive, the combination is known as an autotrain, or, historically, a railmotor train. A steam locomotive provided with the equipment to be used as an autotrain is said to be auto fitted. The autocoach is the forerunner of the driving trailer used with push–pull trains.

A locomotive fitted with additional control equipment is used to power the autotrain. When running 'autocoach first', the regulator is operated by a linkage to a rotating shaft running the length of the locomotive, passing below the cab floor. This engages (via a telescopic coupling) with another shaft running the full length below the floor of the autocoach. This shaft is turned by a second regulator lever in the cab of the autocoach. (See photograph sequence below.) The driver can operate the regulator, brakes and whistle from the far (cab) end of the autocoach; the fireman remains on the locomotive and (in addition to firing) also controls the valve gear settings. The driver can also warn of the train's approach using a large mechanical gong, prominently mounted high on the cab end of the autocoach, which is operated by stamping on a pedal on the floor of the cab. The driver, guard and fireman communicate with each other by an electric bell system.

If more than one autocoach was used, the locomotive would usually be marshalled between the coaches, as 'play' in the control linkages could otherwise make operation difficult. This arrangement was not always possible where turntables were not convenient for turning coaches and hence up to two autocoaches could follow or lead a locomotive with cab ends away from the locomotive. Many GWR suburban services around Plymouth were formed of fixed autotrain formations of four autocoaches, two each side of the locomotive with cabs leading in each direction. When these were introduced in 1906, experiments were made to harmonise the appearance of the locomotive in the middle of the train by cutting down the side tanks and encasing the entire locomotive in a square bodyshell of the same basic design, height and width as the coaches, complete with 'windows' and the same chocolate/cream paint livery. Two 2021 Class and two 517 Class engines were modified in this way.

On 15 April 1923, carriage No. 70 formed a passenger train hauled by locomotive No. 215. The train was in a head on collision with a freight train at Curry Rivel, Somerset due to a signalman's error. Nine people were injured. On 16 November 1937, an empty train in a siding at the eastern end of Ealing Broadway station (between platforms 2 and 3) was waiting to be called into the platform to form the next service to Denham when the driver started the train in thick fog without noticing that the points were not set for the platform nor that the signals were against him, and the auto trailer crashed into the signal box. This auto trailer, no. 211 of Diagram A31, had been converted in August 1935 from steam rail motor no. 81 (Diagram Q1); it was repaired after the accident, and was not withdrawn until March 1959.

+ Fleet list Year Diagram Lot no. Fleet no. Length Notes Preserved examples 1904 A 1055 1 59 feet (18 m) 1904 B 1055 2 70 feet (21 m) 1905 B, V, W, X, A4 1081 3–6 70 feet (21 m) 1905 C 1090 9, 10 70 feet (21 m) 1905 E, F 1108 29–34 70 feet (21 m) 1906 M, M1, A8 1108 18, 35 54 feet (16 m) 1907 N 1126 36–41 59 feet (18 m) 38 at the Telford Steam Railway 1906 L 1130 49–52 70 feet (21 m) 1908 L 1160 71, 72 70 feet (21 m) 1909 R 1394 159–170 59 feet (18 m) 163 at the South Devon Railway167 at the Chinnor & Princes Risborough Railway169 at the West Somerset Railway 1930 A28 1480 187–196 62 feet (19 m) 190 at the Didcot Railway Centre 1934 A23 517 Class 0 4 2T 86 1868 – Some fitted with auto gear after 1905 1076 Class 0 6 0ST/PT 21 1870 – Some fitted with auto gear after 1905 1854 Class 0 6 0PT 1 1890 No. 1728 auto fitted at some point in the 1920s; withdrawn February 1932 2021 Class 0 6 0ST/PT 27 1897 Some fitted with auto gear after 1905 4575 Class 2 6 2T 15 1927 5572 Certain locomotives of this class fitted with auto gear in 1953 4800 Class 0 4 2T 75 1932 1420, 1442, 1450, 1466 Auto fitted version of 5800 Class later renumbered as 1400 Class 5400 Class 0 6 0PT 25 1930 – All auto fitted 6400 Class 0 6 0PT 40 1932 6412, 6430, 6435 Smaller wheel version of 5400 Class, all auto fitted