The first PBM flight occurred on February 18, 1939. 1,235 were built with the last one being delivered in April 1949. Mariners built prior to 1946 were flying boats, and all that followed became amphibious with the addition of the retractable tricycle landing gear.
Though less numerous than the famous PBY Catalina, Mariners played important roles both in World War II and Korea. Since they were a later design they exhibited a marked superiority in performance and overall battle-worthiness.
The Mariner in the Pima Air Museum collection is the last one known to exist. It's an example of the last series built, the A series. These served in the anti-submarine role for the U.S. Navy and as air-sea rescue aircraft for the U.S. Coast Guard.
There is however another PBM-5 and its wresting on the bottom of Lake Washington. The PBM-5 currently rests in approximately 80 feet of water and 6 feet of silt near the south end of the lake. The Cedar River enters the lake nearby bringing a large volume of silt each fall and spring. Over the past 40 years the PBM-5 has been slowly covered. Only the occasional Navy salvage attempts keep the plane from being completely covered.
Forty-eight years ago, Lt. Ralph Frame was taking the PBM from the naval station at Sand Point to a storage hanger at the south end of the lake to be mothballed. Frame landed safely but missed a tie-up buoy while taxiing to shore. Unable to turn around he ran the plane over a small pier damaging the flotation pontoon on the starboard wing. With uneven flotation the plane turned on its side. By the time the PBM hit the bottom it had completely flipped and came to rest in an inverted position..
Used for reconnaissance, rescue work and anti-sub patrols, PBMs were credited with sinking 10 German U-boats during W.W.II. The aircraft was powered by two 14-cylinder Wright R-2600 radial engines. Armament included bow and tail turrets, waist guns, and a 2000-pound bomb payload. A crew of seven to ten manned the plane.
Twice the Navy has attempted to salvage this aircraft and both times personnel were injured in the attempt. The first attempt in 1990 cleared much of the silt from around the aircraft. Because it was unclear at the time weather the Navy had the right to salvage the plane form Washington State waters the attempt was abandoned. In this attempt a Navy diver became ill and died, reportedly of a heart condition. The second attempt came in 1996 after many debates over the legal right of salvage. The 1996 attempt resulted in one diver getting a case of decompression sickness. The Navy made an attempt to pick the plane up by its tail. The PBM was far too week to be lifted in this manner and broke apart. The detached section was brought to the surface and loaded on a barge. After this incident the Navy again abandoned the project. The location or condition of the tail section is unclear.
Martin Mariner PBM-5 Image Gallery