Slippery tracks and poor driver training factors in Wellington commuter train crashes

KiwiRail staff inspect the Metlink Matangi train after it crashed over a barrier at the Melling Station in Lower Hutt in May 2014. Photo / Mark Mitchell

Slippery tracks, poor driver training and use of brake systems, were behind two Wellington commuter train crashes that injured passengers, investigators have found.

In April 2013, the Matangi train hit a concrete safety block at the end of the Melling line in Lower Hutt. Three passengers were injured and the train was damaged.

A year later, in May 2014, the same train collided with a stop block. Two passengers suffered minor injuries and the train was extensively damaged.

The Transport Accident Investigation Commission's report into the two crashes found dew forming on the track followed by dry weather made the track slippery. The trains were being driven normally but the drivers were caught unaware by the slippery tracks.

The Commission found the 2014 driver had cannabis in his system. This was a "concern" but it was not believed to have contributed to the crash. The driver no longer works for KiwiRail.

However, both drivers' training was insufficient, and the train's braking system had not been optimised for slippery conditions.

The commission also said standard train speeds as they entered the station left little margin for error if something went wrong, and the stop block at Melling was less effective at absorbing impact than more modern equivalents.

Four urgent recommendations were made to KiwiRail to address issues to do with risk and two were made to the NZ Transport Agency to ensure low-adhesion braking requirements were defined in rail standards.

KiwiRail have already made several changes, including improving train brakes to deal with slippery conditions and reducing the speed that trains can approach Melling Station.

A new stop block has also been installed, and drivers of Matangi trains receive get training in a simulator.

Key lessons from the inquiry:

• Slippery tracks are foreseeable and train braking systems must be designed and tested to work properly under those conditions.

• Train drivers must be adequately trained in how their train's braking systems worked, and to drive within the trains' capabilities.

• When a new train is being commissioned and entered into service, operators should seek feedback from drivers to promptly identify and fix potential performance issues.