HMNZS Manawanui (A09) was commissioned in 1988 as a diving support vessel for the Royal New Zealand Navy. Originally she was built as a diving support vessel, the Star Perseus, for North Sea oil rig operations.

Manawanui is the third ship with this name to serve in the New Zealand Navy. Manawanui is a Māori word meaning “to be brave or steadfast”.

Manawanui has a capability to hold station over a fixed position. She has a triple lock recompression chamber, a crane with 13 tonne lifting capacity, wet diving bell and a small engineering workshop. She also has limited deck cargo carrying capacity.

The divers of the New Zealand Navy who work onboard Manawanui are trained for deep diving with mixed gases, underwater demolition and unexploded ordnance disposal.

An ROV operated from the Manawanui returned photos of the wreck of the MV Princess Ashika, which sank near Ha’apai, Tonga on 5 August 2009.[2]

The vessel was decommissioned at Devonport Naval Base on February 23, 2018.[3][4]

In July 2018 the ship was sold to the Major Projects Group, an Australian demotions company, and has been renamed as the MV Ocean Recovery.[5] The ship will be used by the Major Projects Foundation[6] (which was founded by the company) as a research and education vessel, with a focus on investigating and preventing oil spills from sunken ships in the Pacific.[7][8]

The new owners, Paul and Wilma Adams, plan to base the ship at Carrington, part of the Port of Newcastle, New South Wales, Australia. They plan for the ship to be the diving base for work in Chuuk Lagoon (Truk) and more generally in the Federated States of Micronesia, where the US Navy conducted Operation Hailstone in 1944 and sank numerous warships of the Imperial Japanese Navy along with merchant ships. They plan for cathodic protection to be applied to the wrecks, to reduce the chance of further discharge of bunker oil into the lagoons

HMNZS Manawanui was a naval tug which was modified for use as a diving tender by the Royal New Zealand Navy (RNZN). Originally intended for service with the United States Navy as a tug, the vessel was built in 1945 and transferred to the New Zealand Marine Department, which employed her in Waitemata Harbour before transferring the ship to the RNZN in 1948. She was converted to a diving tender in 1953 and served out her time in the RNZN in this role, before being decommissioned in 1978 and sold to the Paeroa Historic Maritime Park. The engine is now on display at the Whangarei Stationary Engine Club.^[1]

Construction and design[edit]

Manawanui was built in Auckland in 1945 by Steel Ships Ltd. Displacing 125 tons standard, the vessel was 23 m (75 ft) long and had a beam of 5.6 m (18 ft). Propulsion was provided by a single 320 hp (240 kW) diesel engine operating a single shaft, which produced a top speed of 10 knots (19 km/h; 12 mph). She had a crew of four.^{[citation needed]}

Operational history[edit]

The vessel was originally built for the United States Navy, and was designated as US Navy tug YLT622, but instead she was transferred to the New Zealand Marine Department who named her Tug 622 and used her to service the large post-war fleet of surplus ships scattered around Waitemata Harbour.^{[citation needed]} In 1948, Tug 622 was transferred to the RNZN and became HMNZS Manawanui. Manawanui was the first of three boats with this name to serve in the New Zealand Navy. It is also a Māori word meaning “to be brave or steadfast”.

In 1953, she was converted to a diving tender and functioned in this role for the next 15 years. In 1956, she assisted in recovering an Avenger aircraft that had ditched in Hauraki Gulf. In 1957, she towed the badly damaged patrol launch SDML P3561 off rocks near Rangipukea Island and beached her in a nearby bay. In 1958, she investigated the wreck of the coaster Holmglen off Timaru.^{[citation needed]}

She was replaced as a diving tender by a specially modified Moa class boat with the same name in 1978. In November 1978, she was sold for a nominal sum, to the Paeroa Historic Maritime Park for preservation and display.^[3]