An investigation has found extreme sleepiness caused a locomotive driver to overrun a stop and travel an additional 15 kilometres.
In May 2007, the driver failed to stop at Seddon in Marlborough on the South Island main north line and travelled towards Vernon.
The Transport Accident Investigation Commission says the train driver had been awake for 11 hours prior to his shift, meaning he had been up for 20 hours before the incident.
He suffered from a sleep disorder, had not had adequate food to sustain a long period of duty and had not taken a personal needs break.
Among the commission's safety recommendations is that the modern computerised Tranzlog vigilance system should be used.
It says this monitoring technology is about five years old and would reduce the risk of further fatigue-related driver incidents.
Rail and Maritime Transport Union general secretary Wayne Butson says many of the issues raised in the report have been addressed.
But he says a new radio system should be put in place that would enable data transfer between trains and a control centre and include monitoring via GPS to ensure the engineer is actually operating the train.
