On 29 January 2007, the centre bogie of a tram became derailed at points on the approach to Birmingham Snow Hill terminus. There were no injuries and no significant damage to the infrastructure as a result of the derailment.
The immediate cause of the derailment was the interaction between the tram wheel and the switch tip, causing the wheel to climb onto the top of the rail. Causal factors were the left-hand switch rail not being restored to the correct geometry following repair, and the tram’s left-hand wheels being biased towards this rail. A contributory factor was the switch blade not being subject to an appropriate inspection after repair. Underlying causes were the lack of staff with sufficient competence to inspect and maintain the points adequately, and insufficiently prescriptive standards and procedures.
RAIB has made four recommendations as a result of this incident. These are aimed at:
the competence of staff
standards and procedures for inspection, maintenance and repair.