Interislander’s Kaitaki ferry will resume passenger services tomorrow after effectively being out of action for more than two months.

On January 28, the ship declared a mayday with 864 people on board when it lost power in Cook Strait and started drifting towards Wellington’s South Coast.

After being given the all-clear to take passengers again for the first time in five weeks, Kaitaki was back sailing for less than 24-hours before a problem with its gearbox was discovered on March 4.

Interislander executive general manager Walter Rushbrook said the gearbox repair has gone well.

“The Kaitaki repair was complicated, requiring a particular type of metal for the gearbox that was manufactured and shipped from Germany, along with specialist technical support from the Netherlands. The gearbox failure was a surprise, given it was overhauled late last year in drydock.”

The Kaitaki is now ready to resume passenger sailings following sea trials, KiwiRail’s own assurance checks, and independent third-party signoff, Rushbrook said.

”We are pleased to advise everyone booked to travel from tomorrow that they can cross the Strait as planned, beginning with about 500 passengers due to be welcomed aboard Kaitaki for a scheduled sailing at 0845am.”

New Interislander bookings have been on pause to keep available space open for disrupted Kaitaki passengers. These will be reopened later this week, Rushbrook said.

“Our focus over the past few weeks has been on restoring Kaitaki to service and offering customers booked to sail on Interislander as much certainty as possible about their travel.

“Throughout this disruption we have managed to rebook the vast majority of passengers on alternative sailings. Everyone booked over the Easter weekend was offered a passage across the Cook Strait. Unfortunately, in some other cases we have had to cancel bookings and provide customers with a refund.”

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Rushbrook acknowledged the situation has not been easy for passengers and he apologised for the inconvenience cancellations have caused.

Two new mega-ferries are being built at Hyundai-Mipo Dockyard in South Korea to replace the increasingly unreliable Interislander fleet. They are due to arrive in 2025 and 2026.

In the meantime, KiwiRail is looking at what it can do over and above its already extensive process to improve the resilience of the current ageing fleet, Rushbrook said.

“This includes taking our ships out of service more regularly for maintenance checks in wet and dry dock environments and instituting a new approach to managing our assets and fleet.”