WELLINGTON - The new Tranz Rail interisland ferry Aratere has been detained by the Maritime Safety Authority.
The action comes after a complete power failure on the ship yesterday morning, which saw the Aratere stranded in the middle of Wellington Harbour.
The Notice of Detention served on the ferry means it cannot operate commercially until the cause of the power failure has been discovered and remedied.
Tugs had to rescue the new ferry after it drifted in Wellington Harbour without power and with 220 passengers on board.
The problem-plagued ferry broke down shortly after leaving the Wellington ferry terminal for its 6.30 am sailing to Picton.
The power cut - the fourth problem since Aratere's December launch - was the most serious since the ship resumed service this month, according to Tranz Rail.
An electrical fault cut fuel supply to the ship's engines within five minutes of its leaving the ferry terminal.
Following this, its emergency generator failed to activate the power supply.
The failure left passengers stranded in the dark on the harbour for almost three hours because the ferry Arahura had to leave before the Aratere could berth again.
About 9.30 am it was towed back to the terminal by a tug, after which alternative arrangements were made to get passengers across Cook Strait.
"Yesterday morning the vessel's power failed, and the back-up generator, which would have provided emergency support, also failed," said the director of the authority, Russell Kilvington.
"Fortunately the calm conditions meant that the ship was not drifting and there was no need to drop anchors."
The Aratere, built in Spain at a cost of more than $100 million, has suffered a large number of problems since it was launched in December.
This latest problem is the first that the authority has considered a major safety threat.
"It was fortunate indeed that the incident happened in the middle of Wellington Harbour on a calm day," Mr Kilvington said.
Tranz Rail hopes the Aratere will be back in service today and says there is provision for the cost of the breakdowns to be charged back to the Spanish shipyard which built the vessel. - NZPA
Pictured: The problem-plagued Aratere being towed in Wellington Harbour. HERALD PICTURE / MARK MITCHELL