Boeing has successfully delivered the 21st P-8A aircraft to the US Navy, the final delivery of 2014.
The eighth P-8A will replace the navy's ageing fleet of turbo-prop P-3 Orion aircraft and has already joined other P-8As deployed to train navy crew members.
Boeing Mobility, Surveillance and Engagement vice-president and programme manager Jimmy Dodd said: "Our US Navy and P-8 industry team continues to meet milestone after milestone on this world-class programme.
"We're delivering an aircraft that is providing superior capabilities to the men and women in uniform."
A derivative of Boeing's next-generation 737-800 commercial aircraft, the P-8A can be used for long-range anti-submarine warfare, anti-surface warfare, and intelligence, surveillance and reconnaissance missions.
The navy's Patrol Squadron (VP) 5 Mad Foxes are currently executing operational missions as part of the second abroad deployment of a P-8A Poseidon squadron.
The VP-16 War Eagles registered 600 sorties and 3,500 flight hours on the P-8A's maiden deployment last year.
VP-16 squadron commanding officer commander Daniel Papp said: "We put the Poseidon to the test.
"We tested the aircraft, our aircrew and the logistics tails. Across the board, detachment after detachment, the message was Boeing delivers us a reliable and dependable aircraft, and our crews got on station and knocked it out of the park."
Boeing, which is currently under contract for 53 P-8As, is building the aircraft in collaboration with CFM International, Northrop Grumman, Raytheon, Spirit AeroSystems, BAE Systems and GE Aviation.
Image: The US Navy's Poseidon aircraft departing Boeing's field in Seattle, US. Photo: courtesy of Boeing.