September Mystery Airplane Contest

Glenn Luther Martin (1886-1955) taught himself to fly in 1909 in a homebuilt pusher. He set up his first aircraft manufacturing plant in 1911 at Santa Ana, California. Not only did he build airplanes, but acted in the 1915 silent movie The Girl of Yesterday as a pilot opposite Mary Pickford.

Over the course of Martin's career, he employed such names as William Boeing, Donald Douglas, Lawrence Bell, and James McDonnell.

Martin is often connected to bombers, but beginning in the late 1920's it added flying boats to its stable. This started with Naval Aircraft Factory designs, like the P2M and P3M, and progressed to the Martin Model 130 Clippers for Juan Trippe's Pan American Airways, then to the PBM Mariner, one of the Navy's premier boats in World War II and Korea. Although only built in small numbers as a transport, not a patrol bomber, the giant Mars was for a time, the world's largest flying boat.

With the wartime Catalina, Coronado, and Mariner in need of replacement, Martin proposed their Model 237 based on the Mariner and a hull redesign supposedly based on the Japanese Kawanishi H8K Emily. First flown in May 1948, the XP5M-1 paved the way for 167 P5M-1 Marlins. Powered by a pair of 2790 hp Wright R-3350-30 Cyclones, the big boat had a span of 118 feet 2 inches and range of over 2,800 miles. Designed for anti-submarine duty with a crew of eight, they entered service in 1952 with the Navy and Coast Guard. The French Navy's Flottile 27 at Dakar, Senegal, was equipped 10 Marlins in 1959. One-hundred nineteen of a more advanced version, the P5M-2 with 3450 hp R-3350-32W Cyclones, appeared in 1954. Marlins saw duty during Vietnam for surveillance and to prevent supplies being delivered to the enemy. They were retired in 1967.

Bu-135533, a veteran of VP-40, was the last operational Marlin. It made its last official flight on 6 November 1967 at NAS North Island. It was overhauled and flown to NAS Patuxent River in 1968 and delivered by barge to the National Museum of Naval Aviation, Pensacola in 1976. I photographed it in April 2010.

Gary Kuhn is this month's winner, correctly identifying the Navy's last operational flying boat. Other correct responses came from Ed Wells and Dave Lundgren. One Martin Mariner remains at Pima and two firefighting Mars boats, the Hawaii Mars and Philippine Mars, operated with Coulson tankers in British Columbia for many years. Bu-135533 is the sole surviving Marlin. Blue skies and fair winds for fall. Brief carefully and fly safely.