[Llarry]

Another look at the last of the flying boats: The Martin P5M (new P-5) Marlin.

The flying boat (and amphibious flying boats which could also operate from runways) had been an important component of the U.S. Navy (and other navies) almost since the dawn of aviation. In World War II the Navy had operated PBY Catalina, PB2Y Coronado and PBM Mariners in both the Atlantic and Pacific. In addition to the aircraft, a sizeable infrastructure had been built to support the flying boats including large and small seaplane tenders. Particularly in the Pacific war, flying boats operated from island bases that did not have airports for landplanes.

After WW2, the Navy developed and deployed one more flying boat, the Martin P5M, which was an enlarged and more powerful version of the PBM Mariner. Based on lessons from the war, the P5M was to be an armed maritime patrol and antisubmarine warfare (ASW) aircraft that could operate from sheltered waters. (Note that no flying boats could normally operate from open ocean areas; the water was simply too rough.)

The increased power of the P5M came from Wright R-3350 18-cylinder air-cooled radial engines with 3,250 hp each, a considerable increase over the predecessor PBM. Despite the power, if the P5M lost an engine it would have to struggle to stay airborne, jettisoning ordnance, etc.

The Navy ended up buying 285 P5Ms during the 1950s. The U.S. Coast Guard got in on the action with almost a dozen but found the maintenance onerous and relinquished their boats to the Navy. The French Navy also got USN P5M-2s (P-5Bs) and operated them from West Africa from 1957 to 1964.

P5M squadrons were based on both U.S. coasts and deployed to Bermuda, the Caribbean and the Mediterranean from the east coast and deployed to the Aleutians, and the mid- and Western Pacific from west coast bases. The flying boats were not the only Navy patrol aircraft; land-based patrol aircraft outnumbered them, but the boats could fill gaps in coverage if and when required.

In 1962 the P5Ms were redesignated P-5; the P-5A (old P5M-1) had a conventional tail and the P-5B (old P5M-2) had a T-tail. Both had been upgraded with improved ASW capability as the SP-5A and SP-5B.

But the need for flying boats was reduced dramatically with the advent of the Lockheed P-3 Orion in patrol squadrons. The P-3 had enough range to cover the previous gaps that flying boats had covered and that spelled the end for the P-5 Marlin. It took a few years, with the final SP-5Bs retired in 1967. The retirement of the boats also allowed the retirement of the seaplane tenders, which were all war-built and showing their age.

A note on colors: Post-WW2 patrol planes were painted overall "engine grey." In the early 1960s they began to be repainted in the same gull grey as carrier aircraft, though they had white upper fuselages to minimize heat in the cabins.