How the Mid Wales train collision has all the hallmarks of autumn grip problems and is reminiscent of Salisbury

As investigators arrived to examine October 21’s collision between two Transport for Wales Class 158 passenger trains, it had all the hallmarks of an autumn adhesion problem.

Confirmation came in barely 24 hours later, with the Rail Accident Investigation Branch (RAIB) revealing on the evening of October 22 that it had found evidence that “wheel/rail adhesion was relatively low”.