The first of what could eventually be nearly 200 naval patrol craft is moving down a new assembly line at The Boeing Co.’s Renton plant this week, destined for delivery to the U.S. Navy for testing next year.

The submarine hunter/killer, a modified version of Boeing’s workhorse 737 airliner, could prove to be one of the company’s biggest military programs ever.

The program to design and build the first five test versions of the aircraft, called the P-8A Poseidon, will cost the Navy some $5 billion. The follow-on program to build 108 production versions of the aircraft could cost up to $40 billion, said Bob Feldman, the Boeing vice president in charge of the military side of the Poseidon program.

Around the world, a dozen or more nations are potential customers for the P-8A. India and Australia are near a decision on orders. If they all replace their current naval patrol aircraft with the Poseidon, production could top 200 and revenue to Boeing including support activity for the aircraft could approach $100 billion, Feldman said.

Already, more than 1,800 workers, many of them engineers, are working on the patrol plane program in the Puget Sound area. Hundreds more work at other Boeing locations.

Externally, the plane looks much like a vanilla version of the 737 minus its passenger windows. But inside, the P-8A is equipped for a significantly different mission.

The plane’s job is to seek out submarines – and destroy them if necessary – hundreds of miles from land. The plane will replace the turboprop P-3 Orion in the Navy’s inventory.

The aircraft is equipped with several unairlinerlike features: a bomb bay capable of unleashing five torpedoes on unsuspecting undersea craft; an array of sensors to detect submarines and surface ships; and a powerful communications suite to link the aircraft with the military’s global communications network.

The plane’s wings are equipped with pylons to carry air-to-surface SLAM-ER missiles. Above the cockpit the aircraft has a receptacle to receive an in-air refueling boom.

For all of its military hardware, the most unusual aspect of the P-8A might be the way it’s being manufactured. In the past when civilian aircraft were converted to military uses, the completed civilian aircraft was flown to a modification facility, where it was literally taken apart and major parts of its structure replaced with military equipment.

For the P-8A, Boeing is building the plane from the ground up with many of the military features – the bomb bay and the wing weapons pylons, the refueling port and extra fuel tanks, for instance, – on a duplicate of its commercial aircraft assembly lines next door.

The initial production, handled by Boeing’s Commercial Airplanes Group, takes advantage of the lean production techniques and experience of the commercial airplane division while avoiding the expensive rework necessary in traditional commercial-to-military adaptations, said Mo Yahyavi, vice president of the P-8A program’s commercial side.

Once the plane is largely completed in Renton, it will be flown to Seattle’s Boeing Field, where Boeing’s defense division will install military weapons and sensor systems.

The commercial-military collaboration has thus far produced agreeable results. The program is on schedule and on budget, said Feldman. And the workmanship on even the first example of the plane is superior, said Yahyavi.

The Navy plans extensive tests on the planes, including fatigue and stress tests in Renton and elaborate functional tests at sites around the world.

For Boeing’s World War II-vintage plant, the Poseidon program provides yet another assurance of continued longevity. The new assembly line is in a rehabilitated building that once housed the Boeing 757 assembly program. Given likely orders from other governments, the program will continue at least through 2017, if not longer, at the Renton site, Feldman said.

John Gillie: 253-597-8663

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