Abermule Train Collision - Causes and Lessons

Causes and Lessons

The obvious cause of the Abermule collision was the unauthorised working of the tablet machines by anyone who happened to be around, and the failure of the staff at Abermule to notify each other of their actions. The slack working practices had been allowed to develop over several years by Stationmaster Parry and Signalman Jones.

A contributory cause was the failure of anyone to examine the tablet they received by removing it from its pouch and checking that it was the correct one. Since the system had worked faultlessly for years, it may have been taken for granted. Indeed for anyone to ostentatiously examine a tablet may have been a breach of etiquette, as it would imply that the person handing it over might not be competent or trustworthy. Driver Pritchard Jones and Fireman Owen of the express train were conscientious in inspecting every tablet they received; the crew of the stopping train were not.

Finally, the awkward layout of tablet machines, signals and points levers at Abermule meant that it was possible for conflicting movements to be made. The inquiry recommended that tablet machines be placed in the signal box under the sole control of the signalman, and also that starting signals (which gave engines authority to leave the station) be interlocked with the tablet machines so that they could not be cleared until the correct tablet machine was locked. However, this would involve the rebuilding of the station buildings and signal boxes at Abermule and several other small stations, and it was suggested that alternate single-line sections use the electric tablet system and the older electric staff system; there would be no possibility of mistaking a staff for a tablet. The signalling method continued in use on the line until 1988, when it was replaced by the radio-controlled electronic token block system.

The obvious, though costly, solution to the problems of working single lines would be to double the tracks. As finances allowed, the Cambrian Railway (and the Great Western Railway, which took over the Cambrian after the grouping of 1923) had been slowly carrying out the necessary work. Ironically, British Rail actually removed much of the doubled track and some of the crossing stations as part of the Beeching Axe.