The NSW government has ordered $2.3 billion worth of new trains from South Korea. The problem is that are 20cm too wide to go through existing tunnels.
The Sydney Morning Herald reports the current trains are 2.9m wide, while the new trains are 3.1m across.
Transport for NSW has come up with a solution though: relax current safety standards, and partially modify some tunnels to allow the new trains to run.
The minimum clearance — the space between the carriage and any tunnel walls — needed for NSW trains is 200mm. This allows carriages to sway and tilt on bends.
The new trains infringe on this space, meaning they could come into contact with the tunnel walls.
Proposed modifications to the tunnels will take an additional two years, and an unknown amount of money.
But on the bright side, the 512 new carriages will have mobile phone charging points, accessible toilets and more space for bike racks and luggage.
Business Insider has contacted Transport for NSW and will update this article with their comments.
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