Auckland's new $400 million electric trains will run as slow as their diesel counterparts for at least another year, Auckland Transport says.
Auckland Transport spokesman Mark Hannan said the electric trains would reach their full potential after all 39 diesel passenger trains were removed from the network.
"We can't really get the proper benefit from them until the full rollout when everything is electric, which will be the middle of next year," Hannan said.
Also, new timetables will need to be introduced and software controlling the trains' speed, called European Train Control Systems (ETCS), will need to be reprogrammed to improve transit times, he said.
The ETCS is a protection system to assist train drivers and ensure advised speeds and signal rules are adhered to and to prevent collisions. If drivers operate trains outside a designated speed range the system intervenes to limit speed.
But the Rail and Maritime Transport Union (RMTU) said the 57 new electric trains would not be able to speed up until a costly upgrade of the ETCS software.
RMTU general secretary Wayne Butson said Auckland Transport had bought the cheapest, entry-level ETCS software.
The only way to increase speeds would be to upgrade to more expensive versions, which could handle trains running closer to each other, he said.
"I'm told that Auckland would operate a lot better if it purchased two or three versions higher," Butson said.
Train drivers were frustrated they could not operate the trains to timetable, he said.
"We believe that it was a foreseeable issue."
Twenty new trains have arrived in Auckland with just two operating at any one time.
Hannan said the only benefits from the electric trains noticeable to commuters now would be improved comfort and noise levels.
The average diesel-train speed is about 31kmh on Auckland's Western Line, which is one of the most built-up in the city, he said.
Once all diesel were gone the average electric-train speed along the Western Line would be 35kmh, Hannan said.
The electric trains have a maximum speed of 110kmh, compared to diesel trains which typically have a top speed of 80kmh, with some able to do 90kmh.
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