One of the more complex jobs that Diverse undertook in 2021 was the repair of a commercial tuna fishing vessel that was involved in a collision with an American registered vessel while fishing near the Marshall Islands. The Nelson-based Koorale sustained significant damage to her port side, having been hit amidships in No. 1 port well with such force that fish were blown out of the chutes on impact.

Other vessels in the vicinity came to her assistance, though she was not in immediate danger of sinking. Having effected temporary repairs to the wheelhouse and hull, the crew made their way to Pago Pago in American Samoa where the boat was made properly seaworthy for the return to New Zealand. Koorale arrived back in Nelson about a month after the incident.

Diverse’s assessment of the damage was conducted in conjunction with the owners and the insurers. The aim was to restore the 1973 boat to the same condition as prior to the collision. This involved replacing all damaged areas on the port side of the external hull, which were extensive. The decks, bridge and crew accommodation were all affected, as were the fish wells.

The impact of the collision resulted in a reaction along the ship’s length which also put the engines out of alignment. Pinpointing where this misalignment was located meant going through the entire systems starting with the propeller, right along the shaft, through the gearbox and into the main engine, checking everything. All shafts had to be removed and set up on a lathe to ascertain whether they were still running true. The engine itself wasn’t irretrievably damaged but had to be stripped down and all the bearings checked.

Accommodation areas were also affected by the collision. The insulation used in these areas was highly flammable and, as any hot work up top creates fire risk, all the accommodation below decks was stripped out. The crew quarters on board are now in as-new condition, updated from the vessel’s previous refit 20 years ago.

Diverse also built an entirely new wheelhouse for Koorale. This was constructed in Diverse’s fabrication workshop which is equipped with a full frontage that can be opened. When the wheelhouse was ready to go, a firm specialising in transporting houses uplifted and transported it to the ship, where two cranes were used to lift it in place.

The extensive repair job is ongoing, requiring at least another six months of work. However, due to the collision and resulting US-based court processes, approvals may take some time. Meanwhile, the vessel remains non-operational.