A train driver involved in a crash that injured 14 people did not brake early enough to allow slippery sheets to appear on the line approaching a red signal, a report has found.
The South Western Railway driver “did not apply the train's brakes early enough as it approached the signal protecting the junction to avoid it moving towards it”, the Rail Accident Investigation Branch (RAIB) concluded.
It also found that Network Rail had not “effectively managed the risks” of leaves on the line before the collision in Salisbury, Wiltshire, in 2021.
A train driver and 13 passengers required hospital treatment after the South Western Railway train from London Waterloo to Honiton crashed into a Great Western Railway service from Portsmouth to Bristol passing through Salisbury Tunnel Junction on October 31.
Both trains derailed and came to rest inside the Fisherton Tunnel on the approach to Salisbury station.
The South Western Railway train was almost in a “potentially much more serious collision” with a third train traveling in the opposite direction – a disaster that was avoided by “less than a minute”.
The crash forced the closure of the line between Salisbury and Andover for 16 days as more than 900 meters of new track was laid and almost 1,500 sleepers installed.
The RAIB said the South Western Railway train ran a red signal before the junction because its wheels had slipped due to leaves that had fallen on the line, exacerbated by a spell of wet weather.
He also said Network Rail had not “effectively managed” the track departures with “proactive or reactive measures”.
South Western Railway not effectively preparing its drivers to assess and report low traction conditions was another possible underlying factor, the report added.
The RAIB has made 10 recommendations, seven of which are directed at Network Rail.
The training and competence of staff involved in vegetation management and seasonal delivery were among them.
Andrew Hall, chief inspector of rail accidents at the RAIB, said: “This was a very serious accident and the first time since our establishment in 2005 that the RAIB has investigated the collision of two passenger trains traveling at significant speed.
“The phrase ‘leaves the line' can make some people smile. But the dangers associated with the crushing of the sheets on top of the rails by the pressure of the train wheels, resulting in a slippery layer, are very real and have long been known.
“As with many accidents, this resulted from a combination of many different circumstances, both before the accident and on the day.
“As a result, the barriers put in place to prevent these types of events did not work effectively.”