Five warships, eight P-3 Orion sub-hunting aircraft and an undisclosed number of submarines will be massing off Hawaii’s shores.

No, the flotilla has nothing to do with the Asia-Pacific Economic Cooperation meetings in Honolulu, though it does have its own international flavor.

The U.S. Navy ships and aircraft, a Japanese destroyer and a Canadian P-3 will be participating in exercise Koa Kai 12-1 beginning today.

Koa Kai is a semiannual maritime exercise intended to prepare ships for deployment. Units participating in Koa Kai will conduct flight operations, anti-surface and anti-submarine training, and ship maneuvers, the Navy said.

"We exercise across multiple warfare disciplines to ensure our ships are ready to meet operational requirements when they deploy," said Capt. Dave Welch, commander of Destroyer Squadron 31, based at Pearl Harbor.

Koa Kai is the primary integrated training event in the Middle Pacific to achieve deployment readiness, Welch said.

The guided-missile destroyers O’Kane and Chafee; frigate Crommelin; and underway replenishment ship Washington Chambers are participating, the Navy said.

The Japan Maritime Self-Defense Force helicopter destroyer JS Kurama will join the Navy ships in Hawaii’s waters, marking the first participation of a Japanese surface ship in the exercise.

The Navy would not reveal how many submarines are taking part in the exercise, citing security concerns. The Navy in 2010 said four submarines took part in one of that year’s Koa Kai exercises.

"This kind of training helps the Navy stay ready to maintain a presence in the Western Pacific to help preserve peace and security and further our maritime partnerships with our friends and allies," Navy Region Hawaii said in a news release.

Officials added that Koa Kai "is a great example of our partnership with the Japan Maritime Self-Defense Force. The U.S. Navy and JMSDF frequently operate together and conduct many exercises to increase interoperability.

"This training prepares us to mutually respond to the defense of Japan or to a contingency situation in the Asia-Pacific region, and it builds good bilateral working relationships."

The exercises usually last about a week. Koa Kai supports the Navy’s Mid-Pacific Surface Combatant Operational Employment program, which calls for ships based here to use Hawaii’s waters to conduct intermediate and advanced training.

In the past, Hawaii-based ships sailed to waters off San Diego to train as part of a strike group before deploying, which meant extra time away from families and greater costs.