1. Important safety messages
This accident demonstrates the importance of train drivers who undertake permissive movements in sections occupied by another train at speeds which:
allow them to stop in the distance they can see to be clear ahead
take into account any visibility limitations from the active driving position due to the type of rolling stock and the layout of the place.
2. Summary of the accident
At 10:32 a.m., a Class 20 diesel-electric locomotive entering Platform 2 at Grosmont Station on the North Yorkshire Moors Railway (NYMR) collided with the rear of a passenger train at the ‘stop. The locomotive had just disconnected from a train at Platform 3 arriving from Whitby and was moving to wait behind the train at Platform 2 which was later to leave for Whitby.
The locomotive entered platform number two at about 10 mph (16 km / h) and was due to stop in the unoccupied section of track behind the Whitby service. However, the locomotive collided with the rear of this train at approximately 5 mph (8 km / h).
Five minor injuries were reported among the 175 passengers on Whitby duty, and all were treated by rescuers at the scene. The passenger train cars sustained damage, which was taken out of service for several weeks to allow for inspection and repair. There was no damage to the locomotive, track or other infrastructure
3. Cause of the accident
The accident occurred because the locomotive was traveling too fast to stop within the available distance when the stationary cars ahead first appeared in the driver’s field of vision.
The class 20 locomotive, designed in the 1950s, only had a cab at one end. This means that a conductor’s visibility in the front line is much more restricted when the front end is in the lead, with the conductor having to look through a narrow window beyond the side of the locomotive, in the same way as a steam locomotive driver.
The Class 20 locomotive involved in the crash was privately owned and was made available to the NYMR while some of its own locomotives were undergoing maintenance. It was not expected to be used that day, but it was required shortly after the automatic warning system (AWS) equipment of the scheduled steam locomotive failed a test. Operating. AWS equipment is required for NYMR trains running on Network Rail’s Esk Valley line between Grosmont and Whitby, and the Class 20 locomotive had operational AWS equipment to operate on this section.
The driver was qualified to operate the steam locomotive intended for use on the first Whitby service that day. Even though he had held the relevant skills to drive diesel-electric locomotives, such as the 25-series and 37-series, for about five years, and had driven them on several occasions, he did not have the specific skill to drive the series. 20 used as a replacement. As a result, he enlisted the help of a traction inspector to accompany him. The role of the traction inspector was not to teach the driver how to operate the locomotive but to help him become familiar with the locomotive and its operation and to assess its competence. The North Yorkshire Moors Railway explained that it considered the traction inspector to have overall responsibility for the conduct of the locomotive by the driver.
The conductor and traction inspector were driving Class 20 on the first Network Rail train to Whitby, with a firefighter and cleaner. At Whitby, the locomotive circled the train so that the cab was in the lead for the return trip to platform three in Grosmont.
Once at Grosmont, Class 20 was intended to be replaced on this train by the originally planned steam locomotive, which would carry the train to Pickering and back, on NYMR lines not equipped with AWS. As Class 20 would be required on a subsequent trip from Grosmont to Whitby, the flagman and train crew radioed and agreed that the locomotive would be parked in siding two at Grosmont, from where it was could easily be coupled to the last a service.
To make this movement, the class 20 locomotive had to move forward on the crossing, behind signal 11, then back through platform two. However, passage to siding two was blocked by the presence of the train waiting on platform two for its departure to Whitby. The signaller and the crew intended the Class 20 locomotive to pass from the rear of Signal 11 to the free space of Platform 2, behind the service towards Whitby. The locomotive would then wait there for the Whitby train to depart, before moving to siding two.
This movement of signal 11 was a permissive movement, where a train is allowed to enter a signaling section occupied by another train on the basis that the conductor must stop before reaching the occupying train. The NYMR rulebook and signaling system allow this movement, and it is typically used when hitching a locomotive to a train that is already on the platform. The rulebook requires that a locomotive initiating the movement stop at least six feet from the stationary train. To avoid a collision while traveling, the locomotive must be driven in such a way that the driver can stop it at a distance he can see without obstruction.
The driver began to move from platform three to a position behind signal 11, with the locomotive cab in the lead. He then changed cockpit and began the return to platform two, with the end of the cabin trailing, after signal 11 cleared. He accelerated the locomotive to about the 16 km / h (10 mph) speed limit for the line. The initial part of this movement was in a straight line, with the driver’s view of the line ahead being limited by the body of the locomotive in front of him. Approaching the platform, the line begins to curve to the right and the body of the locomotive further obscures the view of the driver ahead. A reconstruction by the RAIB of the approach and entrance to the platform showed that the driver could not have seen the rear of the last car of the train in front until the front of the Class 20 was at about 16 meters from it.
The traction inspector said he recognized that the locomotive was traveling a little too fast for visibility when it entered the platform. However, before the traction inspector could suggest the driver slow down, the firefighter told the driver he thought he should slow down. The conductor applied a very gentle locomotive brake when the front of the locomotive entered the platform, 27 meters from the rear of the preceding train. The locomotive did not begin to slow until about 20 meters later, after the driver increased the brake application considerably, presumably in response to the firefighter’s request. At that time, the cars ahead were in the driver’s field of vision and the driver put the train brake in the emergency position. However, although the braking slowed the locomotive to about 5 mph (8 km / h), it collided with the rear of the stationary train.
Following the accident, the train conductor stated that although he knew the train was standing on platform number two, he believed it was further down the platform and that there was more space to stop his locomotive. It is also possible that the limited forward visibility compared to that of Class 25 and 37 diesel locomotives and the driver’s unfamiliarity with the operation of this locomotive affected his perception of the speed of the locomotive and his decision making. .
The RAIB considers it likely that these factors combined to cause the driver to enter the platform at a speed at which he could not stop in time to avoid a collision. Although there were four people in the cab of the locomotive when the accident occurred, the RAIB found no evidence to suggest that this caused the driver any distraction.
During its preliminary examination, the RAIB found that NYMR was unable to provide documentary evidence that the traction inspector involved in the accident possessed the relevant driving skills for the Class 20 locomotive. is of concern because it means that the class 20 was operated on the Network Rail infrastructure without the driver or the traction inspector being able to demonstrate the competence relevant to this class of locomotive. The Traction Inspector had worked at NYMR since 1997 and had volunteered for 23 years prior to that. He had maintained and driven all diesel locomotives operated by NYMR. The Office of Rail and Road (ORR) issued an improvement notice on October 7, 2021 requiring the railway to be able to demonstrate the competence of its drivers to operate both on its own infrastructure and on Network Rail’s Esk Valley line.
4. Previous similar events
RAIB report 35/2007 (Collision at Swanage Station) describes the collision between a diesel locomotive and a set of cars that were parked in a platform on a heritage railway line. The locomotive was being driven from its rear cabin and the resulting lack of visibility contributed to the collision. The recommendations were to avoid driving locomotives from the back cabin, where there is a choice, and to plan trips to avoid the risk of collision.
RAIB report 02/2017 (Collision at Plymouth Station) describes a collision between two passenger trains during permissive movement on an occupied platform. A recommendation was made to the railway operator concerning the training of drivers on permissive movements, and to Network Rail on the management of operational risk during authorized permissive movements. It also highlighted a learning point for drivers on how to undertake permissive movements at a speed at which they can stop before any obstacle, taking into account any observation limitations.
The RAIB 08/2019 report (Collision between road-rail vehicles at Cholmondeston) describes a collision which resulted from a vehicle with poor visibility from the line ahead and driven at a speed incompatible with that visibility. The learning points from this survey highlighted the importance for drivers to recognize any visibility limitations when driving such vehicles.