Polmont rail accident

__NOTOC__infobox UK rail accident


title= Polmont rail accident
date= 30 July 1984 17:55
location= Polmont, Central Scotland
line = Glasgow to Edinburgh via Falkirk Line
cause= Animal obstruction
trains= 1
pax= 6 coaches
deaths= 13
injuries= 61The Polmont rail accident occurred on 30 July 1984 at Polmont, near Falkirk, Scotland, when an express train from Edinburgh to Glasgow, travelling at high speed, struck a cow which had wandered onto the track near Polmont station. Several of the carriages were derailed, resulting in 13 deaths and 61 injuries. The accident led to a debate about the safety of push-pull trains on British Rail.

Background

During this period, Edinburgh to Glasgow trains were operated by British Rail on a push-pull basis with a Class 47 locomotive remaining at one end of a rake of carriages. At the other end of the train was a Driving Brake Standard Open (DBSO), a passenger carriage with a cab and set of driver's controls fitted at one end. When driven from this end, the locomotive was controlled remotely by a TDM system whereby signals were sent through the lighting circuits of the train.

The advantage of this system was the reduction in turnaround time at termini as it removed the need to run the locomotive round to the front of the train at each end of the route. However, there was a perceived weakness that in one direction this configuration left a carriage at the front of the train. As the DBSO is lighter than a locomotive (it has an axle load of 8.4 tonnes as opposed to around 20 tonnes), should it collide with anything on the track, it would leave the track more readily.

The Accident

The 17:30 train from Edinburgh to Glasgow was formed of a DBSO, five Mark 3 coaches, and diesel locomotive No. 47707, "Holyrood". After passing through Polmont station at approximately 85mph, the driver saw an animal on the line in the cutting ahead and made an emergency brake application. The train had only slowed slightly when it collided with the animal, later identified to be an adult Ayrshire weighing between 320 and 450 kilograms. Although the impact of the collision destroyed the animal, a significant part of the carcass, later thought to be a leg bone, became trapped under the leading bogie of the DBSO, lifting it off the track and derailing it.

The DBSO ran derailed for approximately 100 metres before veering to the left, running up the edge of the cutting and into trees at the top. It then turned on its side as it was pushed round by the force of the train behind. The second vehicle, after climbing over the rear end of the DBSO, somersaulted end over end, eventually impacting the fifth vehicle as it ran past it, whilst the third vehicle was hit by the DBSO as it fell back down the wall of the cutting after rebounding from the trees. The entire formation, including the locomotive, was derailed. The DBSO and third vehicle were so badly damaged they had to be cut up on site.

Casualties were mainly in the two leading vehicles, and most fatalities were due to passengers being ejected through windows or hit by other passengers or objects as the vehicles were thrown about. The possibility of trains being fitted with seatbelts was raised and rejected, as it would be again 20 years later after the derailment at Ufton Nervet in 2004.

The main focus, however, was that the light axle-loading of the DBSO had led to it being more easily derailed than a heavier vehicle would have been, and modifications were put in place to lessen the chances of a recurrence of the derailment. Again, however, this problem was to be revisited in tragic circumstances in the Selby accident in 2001, where a leading coach of a train being powered from the rear was again derailed by an object (this time a motor vehicle) on the line.

Recommendations

The inquiry [cite book | first=| last=Department of Transport| coauthors=Major A.G.B. King | year=1985 | title=Railway Accident: Report on the Derailment that occurred on 30th July 1984 near Polmont in the Scottish Region, British Railways | publisher= HMSO | id=ISBN 0-11-550685-3 | url=http://www.railwaysarchive.co.uk/docSummary.php?docID=270] made a number of recommendations which were followed, the main ones of which were;

* Object deflectors were to be fitted to the leading vehicles of all trains that had an axle load of less than 16 tonnes.
* Headlights were to be placed on the front of all trains.
* Improvements to fencing where livestock were adjacent to the railway.

References