Whidbey Island will be home for four squadrons of the P-8A Poseidon, the new patrol aircraft that will replace the P-3C Orion, the Navy announced Friday.

The P-8A squadrons will join the fleet no later than 2012, Navy officials said. Other squadrons will be based in Florida and Hawaii.

A fleet replacement squadron will be based at Naval Air Station Jacksonville, Fla., and three fleet squadrons will be based at Marine Corps Base Hawaii Kaneohe Bay, Hawaii, with periodic squadron detachment operations at Naval Air Station North Island in San Diego, Calif.

The decision mirrors the Navy’s preferred placement of the squadrons that was examined in an environmental study released in November 2008.

The homebase decision covers 84 aircraft; 72 aircraft in the dozen P-8A squadrons and 12 aircraft in the fleet replacement squadron. The changeover to the Poseidon is expected to be finished by 2019.