A train which moved with two passengers still aboard its mobility hoist suffered from a lack of communication on several different levels, an investigation has found.
New Zealand’s Transport Accident Investigation Commission (TAIC) recently completed its investigation into the incident, which concerned a KiwiRail Scenic-operated passenger train Capital Connection, travelling from Palmerston North to Wellington.
No-one was injured during the incident.
The train arrived at Waikanae station at 0730 on June 10, 2013. It was fitted with a mobility hoist in the rear-most luggage van for boarding and alighting passengers in wheelchairs.
After stopping, the train manager was monitoring the passenger exchange from the station platform adjacent to the leading passenger car near the front of the train, TAIC’s report said.
When he thought the passenger exchange was complete, he re-entered the leading passenger car and closed all the passenger car doors from the local train door operating panel.
After receiving an ‘all-doors-closed’ green light, the train manager authorised the train driver to depart.
But further down the train, the train attendant had just deployed the mobility hoist onto the platform, and had begun assisting a pair of passengers – one in a wheelchair – off the train.
“As the train attendant deployed the mobility hoist onto the platform, the train manager was radioing the driver and giving him ‘right of way’ to depart,” TAIC said.
“At 0730:09 the train driver moved the throttle to notch 2 and the train started to move, dragging the mobility hoist along the platform with the wheelchair and two passengers still on it.”
The quick-thinking train attendant raised the hoist off the platform, and pressed the train emergency stop button, which stopped the train, having traveled 1.7 metres down the platform.
TAIC found a number of communication issues contributed to the incident.
First, the operation of the mobility hoist that day at Waikanae had not been written into the departure procedure being followed by the train manager.
Second, TAIC found there was no effective means for the train attendant who was operating the mobility hoist to communicate with the train manager.
And third, the status of the luggage van doors – which feature the mobility hoist – was not interlocked with the train door status and control system, which allowed the train manager to receive a green ‘all-doors-closed’ signal, despite the luggage van door being open and the mobility hoist deployed onto the platform.
In response to the incident, KiwiRail has interfaced the mobility hoist controller to give the train controller a ‘train door open’ signal when it is in use. The operator has ensured the train attendant has radio communications with the train controller. It has fitted the hoist with a high-vis material, and it has added a light above the luggage van door where the wheelchair hoist is located, which will stay illuminated until the door is closed.
Due to KiwiRail’s responsive actions, TAIC had no specific recommendations to the operator following the report. But the Commission did have a number of things to say in terms of key lessons learned through the incident.
“Operational procedures must cover an entire operation if accidents and incidents are to be avoided,” TAIC said.
“Good communication among all persons involved in safety-critical operations is essential if accidents and incidents are to be avoided.”
And, “technical solutions to mitigate human error, such as train door interlocking systems, are only effective if they protect all parts of the system.”
The full report is available on the TAIC website: www.taic.org.nz