The Rail Accident Investigation Branch (RAIB) has released an initial report into the train derailment in East Sussex last week, which injured 30 people, revealing a track geometry irregularity near the site.
Track Irregularity Identified
RAIB stated that rear-facing CCTV footage retrieved from train services on 13 August revealed a "track geometry irregularity" on the "immediate approach to the point of derailment" on the line just outside Lewes Railway Station. The preliminary report further noted "there was also evidence of previous track maintenance activity in this area".
The RAIB published an image appearing to show the track had buckled, which can happen during high temperatures. The crash happened on the UK's hottest day of the year so far.
Weather Conditions and Passenger Reports
The RAIB noted that there has been "a sustained period of hot and dry weather", and the nearest weather station to the scene of the accident recorded the ambient air temperature at the time as about 27C.
"Following the accident, RAIB has received several reports of rough riding at the location of the derailment from passengers on other trains," it additionally stated.
Injuries and Damage
Thirty individuals sustained injuries in the incident, with 20 requiring hospital treatment following the derailment that occurred between Cooksbridge station and Lewes Tunnel. "Significant damage" was inflicted upon the train and railway infrastructure.
The derailment occurred at approximately 3.54pm on Thursday, 13 August, roughly one mile north of Lewes station. The preliminary report from RAIB confirmed that train 1F34 consisted of eight carriages.
The rear three derailed and "subsequently overturned during the accident, coming to rest on their sides on the railway's embankment," it stated. The front five carriages remained on the tracks, it additionally confirmed.
Investigation Ongoing
RAIB dispatched its inspectors at 4.02pm to assist the British Transport Police, the Office of Rail and Road, and the railway operators involved.
The RAIB said its investigation will consider the weather conditions on August 13, which were hot and sunny, as well as the status of the track, embankment, condition of the train and the effectiveness of any measures taken to address potential issues caused by hot weather.
