At around 06:53 hrs on 4 February 2016, the 06:25 hrs passenger train from Belfast Great Victoria Street to Portadown collided with an excavator bucket. This had been left on the track near Knockmore Junction, about 1.25 miles (2 km) from Lisburn Station. The train hit the bucket at a speed of 57 mph (92 km/h) and then travelled 330 metres in an upright position before stopping. There were no significant injuries to the people on the train, but the leading vehicle was badly damaged and the track required repair.
The bucket had been detached from an excavator machine undertaking track maintenance work during the previous night when regular train services were not running. The machine driver had forgotten about the bucket. The track safety co-ordinator had not remained near the machine, as required by the rule book, and so was unaware that the bucket had been detached. Other members of the work group had not noticed that it remained on the track as they removed other equipment in darkness. There was no effective process for checking that the track was clear of obstructions before the line was reopened to regular services.
The work group was working within a worksite to which access was being controlled by an engineering supervisor. Although not a factor in the accident, the track safety co-ordinator and engineering supervisor had arranged this access using an informal method that did not meet the rule book requirements.
As a result of this accident, RAIB has made two recommendations addressed to Northern Ireland Railways. The first seeks a formalised process for checking that lines are safe after engineering work is complete and before the line is reopened to regular traffic. The second seeks a review and possible modifications to the formalised communication arrangements used by engineering supervisors controlling access to the railway.
RAIB has also identified three learning points relating to track safety co-ordinators always remaining with their work groups, minimising risks due to objects capable of endangering trains being placed on the line and compliance with formalised arrangements for controlling access to worksites.