Kaitaki breakdown report: “Serious casualty narrowly avoided”

THE NEW Zealand Transport Accident Investigation Commission’s final report into the breakdown of KiwiRail’s ro-pax Kaitaki in January 2023 has set out in stark detail six major system failures and “organised chaos” on board.

The vessel blacked out about one kilometre off Sinclair Head in Wellington Harbour at about 1630 hrs on 23 January, early in a routine voyage from Wellington to Picton. With a series of failures in the engine room, at around 1700, as the vessel drifted closer to rocks on a lee shore in rough weather, Kaitaki’s master issued a 'mayday' and Maritime NZ’s Rescue Coordination Centre initiated their mass rescue plan.

“Numerous agencies got into action, but they did not all share the same picture of what was happening,” TAIC found.

The blackout lasted about one hour, during which anchors arrested the drift. Propulsion was eventually restored and tugs escorted the ship towards Wellington. Near Wellington Heads, a gearbox fault reduced propulsion on one shaft before a standby engine restored propulsion. The ship berthed safely and the mass rescue response was stood down.

The TAIC report outlines six safety issues, including ageing asset management, engineering decision support, emergency response coordination, and national towage capability. It also found planning and practice for a major maritime emergency fell short of requirements. TAIC’s five recommendations targeted practical, system-wide improvements and KiwiRail has accepted all pertaining to the company.

The commission’s final recommendation (below) comes against a recent background of the NZ Government’s decision to dispense with a Cook Strait emergency towage vessel.

“The failure of a single degraded component disabled a key engineering system and as a result all propulsion. A rubber expansion joint (REJ) ruptured and most of the water in the engine cooling system drained out, triggering an engine shutdown. The shutdown protected the engine, but it took the crew about an hour to repair the cooling system and restart the engines,” TAIC found.

The failed REJ had exceeded both recommended service life and age limits. The manufacturer of the REJs says they should be no older than eight months when installed, should be inspected annually and replaced after five years. Kaitaki's ruptured REJ. It was already 13 years old when installed in 2018 and 18 years old when it ruptured in 2023. Under KiwiRail's own failure modes and effects analysis (FMEA) system, the REJ was two months overdue for replacement.

The commission identified six safety issues and made five recommendations.

1. Lifetime management of safety-critical components

The Kaitaki’s common cooling system, including the REJs, was a safety-critical single point of failure. Like all rubber components, the rubber in the expansion joint began to deteriorate as soon as it was made — at increasing risk of hardening, cracking and delamination.

Such components need to be managed and replaced in accordance with the manufacturer’s instructions or recommendations from the operator’s FMEA.

• No need for a new recommendation: TAIC highlighted the REJ issue in its preliminary report in May 2023. KiwiRail accepted the recommendation in that report and reviewed REJs and maintenance settings across its fleet. Maritime NZ also required assurance of fitness for purpose and alerted operators to take note of manufacture date.

2. Interislander’s safety management system — engineers

Interislander’s safety management system implementation did not equip on-board engineers with adequate processes to mitigate risks. If the Kaitaki’s anchors had not gained purchase, the ship was at the mercy of the elements and at risk of grounding. Propulsion was crucial.

The TAIC report explains how the ship’s engineering crew would likely have been able to restore power sooner if they’d had structured decision support and guidance for emergencies. KiwiRail is now developing such tools.

Two recommendations are directed to KiwiRail to improve its preparation for, and management of, engine room emergencies:

1. Review planning, training, resourcing and mitigations for engine room emergencies and consider best practices outlined in international conventions, resolutions and guidance.
2. Implement and regularly exercise the decision-support system for its vessels’ engineers.

3. Evacuation standards for older ships

On New Zealand’s ageing Cook Strait ferries, risk management has fallen behind evolving hazards such as vessel age, configuration and operating environment.

The Kaitaki’s crew made the right call to keep people on board while essential systems — like staying afloat — still worked. It would have been difficult and hazardous to evacuate many passengers, including children and older people, into the rough sea with an on-shore wind.

In any evacuation, lives depend on the whole system working well under pressure. To this end, international rules issued in 2016 require newer passenger ship operators to analyse and understand the best options for escape, evacuation and rescue in a major accident.

The TAIC report explains that in New Zealand, those rules should apply to all ferries, no matter their age. This would have caught the Kaitaki, which was built in 1995. Interislander has accepted this and has commissioned analysis and supporting material.

• TAIC has called on Maritime NZ to provide evacuation guidelines to all ferry operators and strongly encourage them to conduct and regularly review Escape, Evacuation and Rescue Analyses, regardless of vessel construction date, based on revised guidance from the International Maritime Organisation.

4. Emergency response

When New Zealand suffers a major maritime event involving a ship evacuation and multiagency rescue response, all responders must be prepared, coordinated, and swift. They must understand their legal duties and role, judge the situation and know the resources they can bring to bear, and whether they’re doing enough.

The TAIC report explains the complexity. In the Kaitaki incident, there were gaps in responders’ common understanding of the response plan or their role in it. All ships should have a plan for working with search and rescue services and should test that plan through regular practical exercises. Interislander did run drills, and some involved RCCNZ, but they were limited and didn’t fully test how the organisations would work together in a real emergency.

• TAIC has called on Maritime New Zealand to prioritise the review of its Maritime Incident Readiness and Response Strategy to reflect international guidance and support regular joint exercising, clear roles and continuous improvement.

5. Maritime Incident Response Team (MIRT)

Duty controllers require access to specialised maritime expertise. They also need decision-making processes to be able to respond effectively to maritime incidents.

The Kaitaki faced serious risks, including loss of propulsion and the potential for grounding, high casualties, and environmental harm. The incident showed the value of formally activating the Maritime Incident Response Team (MIRT) — a formal structure that enables effective oversight for the Director of Maritime NZ to provide cross-agency support across the response.

The director of Maritime NZ did not establish a MIRT. The TAIC report shows that:

• While a decision-making process existed for establishing a MIRT, there was no evidence that it was followed.
• For a prompt response to a significant or major incident, the holder of the Duty Controller role would benefit from better guidance for their decision-making and timely access to expert maritime advice.

6. Emergency towage and salvage capability

New Zealand lacks emergency towage and salvage capability. This puts disabled ships at greater risk of becoming marine casualties with fatalities or serious harm to people and the environment.

In this incident, with severe conditions near a lee shore, any hasty attempt to tow the Kaitaki would likely have created a second incident because the crews hadn’t trained for it and neither the tugs nor the Kaitaki had the necessary equipment.

Maritime NZ’s safety actions so far have included a trial of a salvage tug (discontinued early 2026), ongoing work to improve long-term capability and a funding model.

• The commission has called for Maritime NZ, the Ministry of Transport and others to continue their work to strengthen salvage and rescue capability where there high risk of very serious marine casualties, particularly mass fatalities.