Norwich-bound train derailment passengers reported 'rough ride'
A driver did not realise his train had derailed despite passengers reporting a "rough ride", an investigation found.
A Greater Anglia service from London Liverpool Street to Norwich on 23 January travelled off the rails for 40m (131ft) when leaving London.
The Rail Accident Investigation Branch (RAIB) found track inspections had not accounted for the risk of derailment on a tight curve at Liverpool Street.
Network Rail said it had "already started to address the issues raised".
The investigation revealed passengers had reported dust falling from the ceiling to the train's senior conductor.
The driver was asked to examine the train because of these reports, and because a signaller reported problems with a set of points used by the train when leaving Liverpool Street.
However, he "saw nothing unusual" when he stopped to look at Shenfield, the report said.
The train continued on to Norwich, travelling at normal speeds of up to 100mph (161kmph).
It was only when the train was examined by a specialist inspector in Norwich that the wheel damage came to light.
A signal maintenance team had also found track damage close to Liverpool Street station by that time.
Trains had to use alternative routes in and out of Liverpool Street station while the damage was repaired.
The RAIB report made three safety recommendations relating to inspections and staff training to prevent a similar incident from happening again.
A Network Rail spokesperson said: "We have the safest major railway in Europe and incidents such as these are incredibly rare.
"[We] will carefully consider their recommendations and take any necessary further action."