Royal New Zealand Navy – RIMPAC Topgun

10 August 2018

It’s a prestigious trophy in naval gunnery, and the Royal New Zealand Navy (RNZN) is bringing it home.

RNZN frigate HMNZS Te Mana has been crowned the winner of the Naval Surface Fire Support Rodeo competition in Hawaii during Exercise Rim of the Pacific (RIMPAC), the world’s largest maritime military exercise.

The trophy was given to the ship that could land five shells the closest to a sea target, from more than 3.5 miles away. Te Mana, using its five-inch main gun, won against stiff competition from warships from the United States, Australia, Chile, South Korea, Peru, Malaysia, Indonesia, India, and Singapore, achieving a mean accuracy of 35 yards.

It is the first time since RIMPAC began in 1971 that a New Zealand ship has won the competition.

Lieutenant Commander Robert Nesbitt, Te Mana’s Operations Officer, said the trophy was sought-after and there was a lot pride on the line.

“The aim of the competition is to prove which ship has the most effective main gun,” Lieutenant Commander Nesbitt said. “The competition is 15 rounds in total. The first five salvos were to conduct a pre-action calibration – effectively ‘barrel warmers’ and to check the system was working.

“The next five were ranging salvos, so the spotters could adjust our fire on to the target. The last five were scored salvos, which counted for the competition. The winning ship was the unit that had the smallest mean miss distance from the target on the last five salvos.”

Te Mana was the first ship on the gun line to open the competition.

“We had drilled and drilled the procedures in the days leading up to the competition, and the weapon technicians on board had carefully selected, monitored and prepared the ammunition days in advance to ensure that the ship had the best chance of success, with the most accurate ballistics we could generate,” Lieutenant Commander Nesbitt said.

Shells and cartridges had to be from the same lot and batch to ensure the grain of powder, weight of shell and performance of fuse was uniform. The temperature where the ammunition was stored was checked regularly, and on competition day all cartridge temperatures were within 1 degree of each other, ensuring the shells would perform as consistently as possible when fired.

The Te Mana crew even asked if they could launch a balloon to determine differences in wind speed and direction at different altitudes, but that was disallowed.

“Guns up, ready for call to fire,” came the call, and the acknowledgement back, “Five salvos fire for effect.”

At 10 seconds apart, the five shots from Te Mana were measured as landing between 16 yards and 50 yards from the target – a mean of 35 yards – thanks to a series of buoys that measured the distance acoustically.

The Commander Third Fleet, Vice Admiral John D Alexander, presented Commander Lisa Hunn, the Commanding Officer of Te Mana, with the trophy at RIMPAC’s closing conference.

Commander Hunn said she was proud of what her ship’s company had achieved in representing New Zealand at RIMPAC.

“Both Te Mana’s and the New Zealand Defence Force’s reputation was enhanced through our participation with the sporting events, a highly successful national reception, winning the gunnery competition and through the leadership and combat skills demonstrated at sea,” she said.

RIMPAC was just the start of a six-month deployment through the Pacific and South-East Asia for Te Mana and its crew, she said.

“We’re looking forward to the remainder of our operation, having gained excellent experience – and made new friends.”

What is RIMPAC?

The world’s largest international maritime military exercise, held every two years since 1971. This is the 26th exercise, running from 27 June to 2 August in Hawaii and San Diego.

By the numbers:

26 nations
47 surface ships
5 submarines
18 national land forces
200 aircraft
25,000 personnel

NZDF’s contribution:

1 warship
3 aircraft
More than 300 personnel


This page was last reviewed on 7 February 2019.