The Polmont rail accident, also known as the Polmont rail disaster, occurred on 30July 1984 to the west of Polmont, near Falkirk, in Scotland. A westbound push-pull express train travelling from Edinburgh to Glasgow struck a cow, which had gained access to the track through a damaged fence from a field near Polmont railway station. The collision caused all six carriages and the locomotive of the train to derail, killing 13people and injuring 61others. The accident led to a debate about the safety of push-pull trains on British Rail. Background The accident happened on one of the busiest commuter lines in Scotland. At the time of the accident, British Rail passenger trains between Glasgow Queen Street and Edinburgh Waverley were operated by the push-pull technique with a single British Rail Class47 locomotive located at one end of the train at all times (the locomotive usually pulled the carriages from Glasgow to Edinburgh and pushed them on the return journey). At the other end of the train was a Driving Brake Standard Open (DBSO). DBSO carriages were introduced on the line in 1980 and consisted of a passenger carriage with a control cab at the front for the driver; a DBSO would be situated at the front of the train allowing the driver to control the locomotive with a set of remote controls from which control signals were sent through the lighting circuits of the train to the locomotive pushing from behind. This system meant that the train could continuously run between the two cities without having to allow time to switch the locomotive to the front of the train between departures. However, it left the front of the train vulnerable when being pushed from behind because the front end was lighter than the rear and had the risk of being pushed over an obstruction, leading to derailment. Accident On Monday 30July 1984, a westbound express train, the 17:30 service from Edinburgh Waverley to Glasgow Queen Street – consisting of a British Rail Class 47/7 diesel-electric locomotive pushing five Mark 3 coaches and fronted by a DBSO (no. 9706) – made a scheduled stop at Linlithgow station and accelerated to approximately , passing through Polmont station shortly afterwards. To the west of Polmont, the track curved left and passed the junction for Stirling, then curved right with a steady gradient towards Falkirk High station. After passing the junction the train driver,