Under water at Renton, Washington

The Martin PBM Mariner was a patrol bomber flying boat of World War II and the early Cold War period. It was designed to complement the PBY Catalina in service. 1,366 were built, with the first example flying on February 18, 1939 and the type entering service in September 1940. HISTORY

Here you can see there was a big crew inside her hull. See her FLYING

 Photo is redrawn from image at: http://www.vectorsite.net/avmars.html     

The designation PBM-5 appeared as the final version of the XPBM-1 Mariner. The PBM-5 model sported improved defensive armament (no fewer than 8 heavy caliber machine guns) Pratt & Whitney radials and AN/APS-15 series search radar.  She was a twin engine flying boat with a high-mounted monoplane gull wing, twin tail rudders, retractable stabilizing floats and a deep hull-like fuselage. SOURCE

A crew of 7 to 9 men operated the ship. Armament generally positioned at the bow, tail and dorsal positions with an additional 2 machine guns at the beam (waist) positions firing through hatches. The bombload was a respectable 8,000 pounds. 1,717 were produced covering various models for use by American and British forces.

Classification Type: Maritime Reconnaissance Flying Boat        Contractor: Martin Company - US
Length: 79.82ft      Width:118.01ft      Height: 27.49ft      Max Speed: 211mph
           Max Range: 2,240miles       Rate-of-Climb:452ft/min        Service Ceiling: 19,800ft (3.7miles)

The Navy made an attempt to pick the plane up by its tail. The PBM was far too weak 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.


See a larger Plane by Martin - the Water Bomber

If an aerial photo were taken when the PBM-5 sank, it would have looked something like the image at left.

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 few decades the PBM-5 has been slowly covered. Only the occasional Navy salvage attempts keep the plane from being completely covered.

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. the image below displays what had been dug out.

When the PBM was being moved from the naval station at Sand Point to a storage hanger at the south end of the lake to be mothballed, The plane landed safely but missed a tie-up buoy while taxiing to shore. Unable to turn around, the plane ran 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.