Summary

  • There was a track "irregularity" on the approach to the site of a train derailment near Lewes last week, an initial report has found - see a photo taken before the incident

  • The Rail Accident Investigation Branch has been investigating the derailment, which saw three carriages of a Southern Railway service from London Victoria flip on their side near Lewes

  • Around 150 people were on the train - one passenger told the BBC it felt like "we'd been lifted into the air", while another said when the train stopped they "were stood on the glass of the windows"

  • The report says there is evidence that "some movement" had previously taken place on the railway embankment, but there is no evidence of a significant slip

  • Thirty people were injured with 20 taken to hospital - two passengers who suffered serious but non-life threatening injuries remain in hospital

  • The railway between Lewes and Hayward Heath will be closed for at least one more week as the train is recovered and tracks are repaired

  1. CCTV, track irregularity, hot weather - a look at what this report sayspublished at 13:09 BST

    Katy Austin
    Transport correspondent

    Investigators say CCTV from the train which derailed near Lewes last week, and other trains which used the line on the same day, shows there was an "irregularity" with the track geometry just before the point where the train came off the tracks.

    The Rail Accident Investigation Branch said it had received "several reports of rough riding at the location of the derailment from passengers on other trains". Its initial update also highlights that the accident took place during a sustained period of hot and dry weather.

    It says the clay embankment and the material underneath it are sensitive to changes in moisture content, and may move as moisture levels change. The RAIB says there is evidence that some movement had previously taken place, but no evidence to indicate a significant slip before the accident.

    The rest of the investigation will now consider elements including:

    • how that section of track was inspected and maintained
    • the condition and maintenance of the embankment
    • the weather conditions and how effective any hot weather mitigation measures were - intended to address the risks of operating trains in hot weather

    The train was travelling at around 65mph, as it approached the point of derailment, within the 70mph speed limit. Three carriages of the train from London to Victoria to Eastbourne came off the tracks on Thursday afternoon.

    They ended up on their side down an embankment. Twenty people needed hospital treatment, with two seriously injured. The RAIB has today released its initial update. Its full investigation continues.

  2. Rail investigators received reports of 'rough riding' at 'irregularity' spotpublished at 13:08 BST

    We can now bring you more on the "irregularity" the report has identified on the train track where the derailment occurred.

    It says that a "track geometry irregularity" existed on the approach to the site where the train derailed "prior to the accident occurring".

    As well as this, there was "evidence of previous track maintenance activity" in the area.

    And since the incident, the Rail Accident Investigation Branch says it has received "several reports of rough riding" at the same location, from passengers on other trains.

    It also marks on the rails are "consistent with the wheels of the derailed rear vehicles having climbed over the rails".

    Image of three carriages of train falling off tracks from an aerial point of view
    Image caption,

    An aerial shot of the train of which three carriages fell off the tracks in Lewes, East Sussex

  3. Driver was braking at point of derailment - reportpublished at 12:56 BST

    The report has also looked at the speed which the train driver was going at the time of the accident.

    The RAIB said that the train was travelling at 65mph at the time of the accident, which is within the 70mph speed limit for the area.

    Data also shows that the driver had applied the brakes at the point where the train derailed, and that the train had started to decelerate.

  4. Thirty people injured during train derailmentpublished at 12:53 BST

    A train on its side next to an embankment with workers under a tent watching onImage source, Network Rail/PA

    Around 30 people were injured, 20 of whom required hospital treatment and some had "serious injuries", this initial report says.

    Authorities previously said two people had serious but not life-threatening injuries.

    "Significant damage was caused to the train and to railway infrastructure," the report adds.

  5. Evidence of 'some movement' in embankment under tracks - reportpublished at 12:50 BST

    The report says the accident took place "during a sustained period of hot and dry weather" - on the day, it was "hot and sunny, with little wind" and around 27C (ambient air temperature).

    The embankment on which the railway runs is constructed of clay, sitting on alluvial/alluvium deposits, "consisting of loose clay, silt, sand and gravel", the report outlines.

    These are sensitive to changes in water content and could move as moisture levels change, the report says.

    It adds there is no evidence that a significant embankment slip occurred before the accident at this stage. However, there is evidence that some movement had previously taken place

  6. Photos of track 'irregularity' included in reportpublished at 12:44 BST

    The RAIB report also includes CCTV images from a different train, which appear to show the irregularity in the train tracks it has found.

    In the image, taken from a train that passed through at 14:04 BST on the same day, it shows a irregularity "adjacent to the white ballast bags", the report says.

    A CCTV image of a track with a kink in one of its rails.Image source, Greater Thameslink Ralway / RAIB
    Image caption,

    The RAIB says an "irregularity" could be seen on the tracks over an hour before the derailment

  7. 'Track geometry irregularity prior to accident' - reportpublished at 12:36 BST
    Breaking

    The Rail Accident Investigation Branch has released its initial report into the incident, which took place at about 15:44 BST on Thursday, 13 August.

    It says that a "track geometry irregularity" existed on the approach to the site where the train derailed "prior to the accident occurring".

    Stay with us as we bring you more updates from the report as they become available.

  8. Derailment investigation's initial report releasedpublished at 12:36 BST
    Breaking

    The initial report from the investigation into Thursday's derailment in Lewes, East Sussex, has just been released by the Rail Accident Investigation Branch.

    We are looking through it now and will bring you the key lines as we get them.

  9. Analysis

    What do investigators look at?published at 12:27 BST

    Katy Austin
    Transport correspondent

    Two emergency workers sat in hi vis with equipment next to themImage source, PA Media

    We're anticipating an update today including some initial facts. It's still early stages in the overall investigation though - the final report won't come out for a while.

    We know that experts from the Rail Accident Investigation Branch have been examining the accident site and the train itself, and taking a close look at the infrastructure.

    Other evidence includes CCTV, data downloaded from the train, and signalling data.

    Their job is to piece together what happened and come up with recommendations to stop something like this happening again.

    Other investigations are done by the industry, and by the safety regulator the Office of Rail and Road.

  10. 'It felt like we'd been lifted into the air'published at 12:01 BST

    Rachel Heath, who caught the affected train, told BBC Radio 4's Today programme she felt like "we'd been lifted into the air".

    "Everyone was screaming and I just remember looking around and seeing so much panic and fear in people’s eyes, and all of a sudden it felt like we’d been lifted into the air and then came back down and the train just fell on to its side," she said.

    Tracy McGregor was also travelling on the train, in carriage seven - one of the coaches which left the tracks.

    She told the BBC: "When the carriage left the tracks, it felt like it went on forever.

    "I took the brace position, I was preparing to die.

    "When the train did stop, we were stood on the glass of the windows but the carriage was just full of earth."

    She said the first emergency services arrived on the scene within 10 minutes.

    Picture of a train carriage on its side with the windows lying on the grass, while passengers stand upright in the carriageImage source, Tracey McGregor
    Image caption,

    Tracey McGregor said when the train stopped, she was "stood on the glass of the windows" and the carriage was "full of earth"

  11. What we know about the train derailmentpublished at 11:47 BST

    Three carriages of a passenger left the tracks in Lewes, East Sussex, at around 15:44 BST on Thursday 13 August.

    It happened as the 14:24 Eastbourne-bound Southern service approached the East Sussex town from London Victoria.

    All lines between Lewes and Haywards Heath were closed following the derailment, with railway officials warning disruption will continue until at least August 26.

    A map of south-eastern England. A red line traces a railway route from central London to near the south coast. The start is labelled to explain the train left London Victoria at 14:24 BST. Gatwick Airport station is labelled halfway down the route. The location of the train derailment is labelled in red, just north of Lewes, which appears just north-east of Brighton. A dotted line continues to Eastbourne, where a label shows the train was due to arrive at 15:51.
    A picture of the train showing buckled tracks, three carriages on their side, and the river next to them
  12. Update expected on Lewes train derailment investigationpublished at 11:39 BST

    Railway carriages on their side, stretching from a railway line down the side of a small embankment. Emergency workers crowd at the bottom of the embankment.Image source, Jack Valpy/BBC
    Image caption,

    Authorities are investigating how a train derailed near Lewes in East Sussex

    Good morning.

    We are expecting an update today on the investigation into a train derailment where three carriages of a passenger train tumbled off the track in Lewes, East Sussex earlier this month.

    Two people remain in hospital with serious but non life-threatening injuries and authorities said 18 others were also taken to hospital with less serious injuries.

    They were later discharged.

    A Rail Accident Investigation Branch team has been examining the derailed train and railway infrastructure at the site, in part reviewing CCTV footage and signalling data.

    We expect to receive an update from investigators today. As always, our reporters are poised to bring you the key lines as they come in.