OFF THE COAST OF OAHU, HAWAII — Two U.S. Marine Corps MV-22 Osprey aircraft are embarked on an Australian amphibious ship for the duration of the 2022 Rim of the Pacific exercise, advancing efforts to integrate the two nations’ amphibious forces for operations in the southwest Pacific.

The aviation detachment comes from Marine Medium Tiltrotor Squadron (VMM) 363, stationed at Marine Corps Base Hawaii. This squadron has previously operated in northern Australia as part of the Marine Rotational Force-Darwin. That integration testing and relationship-building have made this RIMPAC pairing possible, HMAS Canberra Commanding Officer Capt. Jace Hutchison told reporters aboard the ship July 13.

Canberra will operate in the biennial international exercise as part of an amphibious task force that includes American ship Essex, Korean ship Marado and Mexican ship Usumacinta.

Hutchison said RIMPAC 2016 featured some early interoperability testing between American MV-22 aircraft and the Australian helicopter landing dock. The Marine Rotational Force-Darwin deployments — with more than 2,000 U.S. Marines on the ground for six months of the year — have allowed for further testing and cross-decking on Canberra and sister ship Adelaide in the years since.

This year, “it’s an opportunity for us to now develop in an enduring manner by having two U.S. Marine Corps MV-22 aircraft embarked for the entire sea phase. That’s something that’s not happened before in the Australian context,” Hutchison said. “We’re really looking forward to expanding the way that we operate those aircraft within the constraints of our platform.”

The captain said Canberra would embark about 275 ground forces from Australia, the U.S., Tonga, Sri Lanka and Malaysia, and the ship would push those ground forces back ashore for an amphibious landing using aircraft that include the pair of Ospreys.

Hutchison said this aviation integration work help clarify the limitations of the ship, the aircraft and the combination of the two.

“Being able to understand the left and right of arc allows you to then plan what sort of operations you can do together in the future. And that’s what we’re trying to do in these three weeks: we’re trying to understand what is the minimum we’re able to do, what is the maximum we’re able to do, and, both countries, what are we authorized to do. And then within that, we’ll work out what our integration really looks like,” the captain said.

Lt. Sam Laidlaw, a flight control officer on the ship, told reporters during the visit the ship takes a more conservative approach to operating with foreign aircraft, as a kind of safety bubble for the ship crew and the aircrew as they aren’t as familiar with each other and how the wind and sea states affect behavior.

Marines had sent some CH-53E heavy lift helicopters to Canberra earlier in the week, Laidlaw said, for familiarization and deck landing procedure training.

“Whenever we do international operations, the most challenging thing tends to be communications,” he said. “We do briefs beforehand; before any aircraft come across here, we sit down and do a face-to-face brief with them. If we can’t do that, we have a PowerPoint presentation we put together where we try and spell out all those little differences.”

The day the CH-53s flew out to the ship, the Australian and American teammates discovered one fundamental issue as the aircraft were on approach: the Australian ship crew was giving its position in true north, and the American pilots were expecting to receive it in magnetic north. The ship was pointed about 10 degrees off from what the Marine pilots were expecting.

“This is the reason why we have more conservative helicopter operating limits, because we don’t all do things all exactly the same way,” Laidlaw said.

Hutchison said Canberra had landed American CH-53s, MV-22s and MH-60 Seahawks, as well as the Japanese variant of the Seahawk, and that he hoped to cross-deck with a few more countries before RIMPAC ends.

“When we operate together in either a peacetime, non-warlike, [humanitarian assistance and disaster relief] scenario, or even in time of conflict, it’s much better to be able to form a partnership and be able to use compatible equipment and compatible forces to create a more efficient outcome,” the captain said.

The Marine Rotational Force-Darwin will participate in the Talisman Sabre exercise in 2023. Hutchison said he expects those forces to continue working on integration between the Canberra-class amphibs and the American MV-22s.

Asked whether there might eventually be a full deployment with U.S. Marines on Canberra or Adelaide, Hutchison said the pairing makes sense if they can work through technical integration issues.

U.S. Marines operate out of Darwin for six months of the year, but there typically aren’t any American amphibious ships nearby to support them.

Canberra and Adelaide have in the past been tasked with responding to natural disasters throughout Oceania and the southwest Pacific. Given that disaster relief is within both countries’ authorities and priorities, “that’s the perfect partnership for us to take out into those regional areas and support as a collective,” Hutchison said.

“There’s no reason why we couldn’t see MRF-D and their aircraft embarking an Australian ship while they’re in Australia,” the captain said, “and in fact we would probably want that to occur just as a continuing development of that partnership.”

Megan Eckstein is the naval warfare reporter at Defense News. She has covered military news since 2009, with a focus on U.S. Navy and Marine Corps operations, acquisition programs and budgets. She has reported from four geographic fleets and is happiest when she’s filing stories from a ship. Megan is a University of Maryland alumna.

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