Executive summary
On Monday 31 July 2006 at about 2054, eastbound express freight Train 826 stopped at Cora Lynn
Arrival Signal 10244 on the Midland Line. The arrival signal was displaying a green aspect, while at the same time the facing points were set in the reverse position and the "L" light was not illuminated.
The locomotive engineer suspected a signalling irregularity because about 2 hours earlier he had set and locked the west-end points in the reverse position when he departed from the crossing loop on westbound Train 841. He had monitored the radio channel during the intervening time and was aware that no other trains had since passed through Cora Lynn.
Safety issues identified included:
- the suitability of the single-line automatic signalling system for the Midland Line
- the inspection and testing of the universal switch controller units
- the procedures for communicating the status of main-line points at crossing stations within single-line automatic signalling territory.
One safety recommendation has been made to the Chief Executive of the New Zealand Transport Agency to address these issues.
Related Recommendations
The current requirements for communicating the status of main-line points at crossing stations within single-line automatic signalling territory results in a potential single point of failure where the consequences could be a high-speed rollover, derailment or collision.