Martin PM-1

The Martin PM-1 was a twin-engine biplane patrol flying boat built for the United States Navy by the Glenn L. Martin Company of Baltimore. It was Martin's production version of the Naval Aircraft Factory PN-12, an open-cockpit, wooden-then-metal-hulled patrol boat lineage that the Navy spread across several manufacturers in the late 1920s. Ordered in 1929 and delivered in 1930, the PM-1 carried a five-man crew on long maritime reconnaissance, scouting and bombing patrols, mounting flexible machine guns and a useful bomb load.

Powered by two Wright Cyclone radial engines, it could cruise for well over a thousand miles, a vital capability for a Navy then learning to extend its eyes far out over open ocean. The PM-1 and the later PM-2 served patrol squadrons through the early 1930s, helping to develop the doctrine and seamanship that would mature into the great wartime flying-boat fleets.