The Kaitaki Interislander ferry leaves Wellington Harbour. Photo: KiwiRail
Interislander's Kaitaki ferry has been missing one of two stabiliser fins for more than 18 months, meaning sailings were cancelled this week due to large swells, while rival operator Bluebridge could continue with a freight-only service.
KiwiRail's fleet of three ferries has stabilisers and "will happily sail choppy conditions", Interislander's website said.
However, Interislander executive general manager Duncan Roy confirmed KiwiRail discovered one of the Kaitaki's stabilisers was "missing" during the ferry's last dry dock in Sydney in September 2022.
"Manufacture and fitting of a new stabiliser could not be achieved during that dry dock and the work was programmed into the vessel's long-term maintenance plan."
Roy stressed stabilisers did not relate to vessel safety. They were about comfort and helped reduce the vessel's movement for passengers and livestock, he said.
The issue had not materially affected the ship's performance, he said.
Stabilisers have to be fitted when a vessel is out of the water at dry dock, Roy said.
A new stabiliser will be fitted during the Kaitaki's next dry dock in Singapore, which is scheduled in August this year.
This will allow the Kaitaki to return to normal swell limits. In the interim, KiwiRail did not sail the Kaitaki in swells of more than 4m, Roy said.
The Kaitaki is the only ferry currently operating in the Interislander fleet, with the Aratere being detained after it ran aground in Picton and the Kaiarahi away for maintenance.
Kaitaki sailings were cancelled this week due to large swells and strong southerlies on Cook Strait.
Bluebridge cancelled its passenger sailings but was able to continue with a freight-only service.
Last night, Bluebridge returned to running delayed passenger sailings as the bad weather abated.
Interislander was only able to return to freight-only sailings overnight and was expected to return to full passenger services by Thursday morning.
The Kaiarahi is on schedule to return from its wet dock at the start of the school holidays on Saturday, subject to successful sea trials, Roy said.
"Having both Kaiarahi and Kaitaki operating from Saturday will ensure passenger and freight capacity over the school holidays.
"We are running a modified sailing schedule for Kaiarahi for a week from Saturday, to support moving more commercial vehicles and rail freight. We expect any weather-related freight backlog should be cleared in a few days."
- This story was first published by the New Zealand Herald.