Fractured rail fastenings caused Eastleigh intermodal derailment
Fractured rail fastenings on a set of points at Eastleigh West Junction caused the derailment of an intermodal train on January 28 2020, according to the Rail Accident Investigation Branch (RAIB) report.
The derailment happened at about 1132 on a Birch CoppiceSouthampton Docks intermodal train, hauled by Freightliner 70001.
A video recording from an earlier passenger train was subsequently found to show missing fastenings on bearers 22 and 24.
As the intermodal train passed over the points, one of the rails moved outwards under the train, breaking further fastenings and causing the locomotive’s wheels to drop inside the rail.
Investigations show the design of the fastenings used made them more prone to fracture when subjected to high lateral forces, which were present at the points due to track geometry and the curving characteristics of the locomotive.
Local track maintenance teams were unable to identify the faults because the fastenings had fractured between 25mm and 30mm underneath the surface of the concrete bearer and the defects were not apparent during visual inspections.
RAIB found that Network Rail had not developed an effective inspection regime to detect these types of failures. It also observed that the Eastleigh maintenance delivery unit was not effectively managing the maintenance of its track assets, and that evidence identified for preservation as part of the accident investigation was lost during track repair work undertaken after the derailment.
RAIB recommended that NR should develop a strategy to assess and control the risk of failure of track fastening systems incorporating elevated shoulders in the RT60 switch and crossing layouts involved in this derailment. It should also confirm the failure mode identified does not apply to other elevated designs of track fastening system.
NR should also review its arrangements for the dynamic measurement of track geometry on infrastructure not covered by its track measurement trains.