Driver fatigue and hunger may have led to a London Underground train travelling at nearly 40 miles-per-hour with some of its doors open, an investigation has found.
The Rail Accident Investigations Branch said 10 doorways remained open when the Jubilee line train made its 56-second journey between Finchley Road and West Hampstead in September last year.
The unnamed Tube driver only became aware of the issue when a passenger activated an alarm inside the train.
None of the 30 passengers on board fell out of the train and nobody was injured.
Investigators found the driver was only getting between four-and-a-half and six hours’ sleep on work days, and would attempt to catch up on sleep on his days off.
They also noted his concentration could have been affected by low blood sugar, as he had not eaten anything for around 13 hours.
The driver said he believed his sleep and meal routine “did not affect his performance at work”.
When the train arrived at Finchley Road station, the usual controls for opening the doors did not function so the driver used an alternative method.
This resulted in a switch being activated that allowed the train to move with open doors.
The RAIB has recommended improvements to door controls, better training for drivers and an improved awareness on the effect of poor sleep and eating patterns.
Transport for London spokeswoman Jill Collis said work has already begun on carrying out several of the RAIB’s recommendations.