Speed and rainfall details emerge as Stonehaven derailment investigation progresses

The latest update from the Rail Accident Investigation Branch (RAIB) has revealed that 52mm of rain fell on the morning of the crash and it has been established that the train was travelling at 117.1km/h – just under the permitted – 120km/h for the track – when it hit the landslide debris.

The latest report details the timeline of events leading up to the derailment of the 6.38am service from Aberdeen to Glasgow Queen Street. The train had stopped as normal at Stonehaven before being halted by a signaller on the up line at Carmont at 6.59am via radio message after a northbound train (on the down line) reported a landslide obstructing the up line path of the 6.38am service between Carmont and Laurencekirk.

The train remained stationary on the up line until 9.25am, by which time the weather had improved, and it was given permission to move north and use a crossover point at Carmont to move onto the down line. After passing onto the down line at 9.36am while travelling at 8km/h the train sped up to reach 117.1km/h.

At 9.38am the train struck the landslip, which covered the down line, causing it to derail. As the track curved to the right, the train continued in a roughly straight line for around 70m until it struck a section of bridge parapet, which was destroyed. The leading power car continued most of the way over the bridge and fell from the railway down a wooded embankment, as did the third passenger carriage. The first passenger carriage came to rest on its roof, having rotated to be almost at right angles to the track. The second passenger carriage also overturned onto its roof and came to rest on the first carriage. The fourth passenger carriage remained upright and attached to the rear power car; it also came to rest on the first carriage. All wheelsets of the rear power car derailed, but it remained upright.

Debris from a drain is believed to have caused the derailment

The report also details initial findings into the cause of the landslip, which originated a drain within the steep slope to the left of the down line. The drain runs northwards along the lower edge of the field (at the top of the slope above the railway) until it reaches an access chamber about 50m south of the landslip area, from where it runs diagonally down the steep slope, passing through two more access chambers, until it reaches an outfall structure at a track level ditch which takes water northwards towards Carron Water. The drain is formed from a 450mm diameter plastic pipe in a gravel filled trench and RAIB reports that water flowing from land above the railway washed some of this gravel onto the railway, together with some larger pieces of rock which had formed part of soil eroded from the sides of the trench.

RAIB has said that the investigation is ongoing and it is still considering the sequence of events and action of those involved, as well as the management of earthworks and drainage in this area, including recent inspections, risk assessments and consideration of the impact of extreme weathe events on the earthworks and drainage.

Transport secretary Grant Shapps has called on Network Rail to deliver a report on the incident by 1 September.

Following the latest update from RAIB, Network Rail chief executive Andrew Haines said: “My thoughts remain with the families and friends of [train driver] Brett [McCullough], [Conductor] Donald [Dinnie] and [passenger] Christopher [Stutchberry] [who were killed in the derailment], and everybody else affected by the tragic events of last week. Our railway family is still in shock.

“We are doing everything we can to support ongoing investigations so that we can properly establish the circumstances that led to the derailment, and to understand what can be done to prevent such a tragedy happening again.”

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