Martin PBM Mariner

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 Consolidated PBY Catalina in service. A total of 1,366 were built, with the first example flying on 18 February 1939 and the type entering service in September 1940.


Martin PBM Mariner
Class Aircraft
Type Utility
Manufacturer Glenn L. Martin Company
Production Period 1937 - 1949
Origin United States of America
Country Name Origin Year
United States of America 1939
Country Name Operational Year Retirement Year
Argentina View
Australia View
Netherlands View
United Kingdom - UK (Great Britain) View
United States of America 1940 1964 View
Uruguay 1940 1964 View
ManufacturerName Production From Production To Quantity
Glenn L. Martin Company 1937 1949 1285 View

In 1937 the Glenn L. Martin Company designed a new twin-engined flying boat, the Model 162, to succeed its earlier Martin P3M and complement the PBY Catalina. It received an order for a single prototype XPBM-1 on 30 June 1937. This was followed by an initial production order for 21 PBM-1 aircraft on 28 December 1937.

To test the PBM's layout, Martin built a ? scale flying model, the Martin 162A Tadpole Clipper with a crew of one and powered by a single 120 hp (89 kW) Chevrolet engine; this was flown in December 1937. The first genuine PBM, the XPBM-1, flew on 18 February 1939.

The aircraft was fitted with five gun turrets, and bomb bays that were in the engine nacelles. The gull wing was of cantilever design, and featured clean aerodynamics with an unbraced twin tail. The PBM-1 was equipped with retractable wing landing floats that were hinged outboard, with single-strut supported floats that retracted inwards to rest beneath the wing, with the floats' keels just outboard of each of the engine nacelles. The PBM-3 had fixed floats, and the fuselage was three feet longer than that of the PBM-1.

The first PBM-1s entered service with Patrol Squadron Fifty-Five (VP-55) of the United States Navy on 1 September 1940. Prior to the outbreak of World War II, PBMs were used (together with PBYs) to carry out Neutrality Patrols in the Atlantic, including operations from Iceland. Following Japan's attack on Pearl Harbor, PBMs were used on anti-submarine patrols, sinking their first German U-boat, U-158 on 30 June 1942. PBMs were responsible, wholly or in part, for sinking a total of ten U-boats during World War II. PBMs were also heavily used in the Pacific War, operating from bases at Saipan, Okinawa, Iwo Jima and the South West Pacific.

The United States Coast Guard acquired 27 Martin PBM-3 aircraft during the first half of 1943. In late 1944, the service acquired 41 PBM-5 models and more were delivered in the latter half of 1945. Ten were still in service in 1955, although all were gone from the active Coast Guard inventory by 1958 (when the last example was released from CGAS San Diego and returned to the U.S. Navy). These flying boats became the backbone of the long-range aerial search and rescue efforts of the Coast Guard in the early post-war years until supplanted by the P5M Marlin and the HU-16 Albatross in the mid-1950s.

PBMs continued in service with the U.S. Navy following the end of World War II, flying long patrol missions during the Korean War. It continued in front line use until replaced by its direct development, the P5M Marlin, with the last USN squadron equipped with the PBM, Patrol Squadron Fifty (VP-50), retiring them in July 1956.

The British Royal Air Force acquired 32 Mariners, but they were not used operationally, with some returned to the United States Navy. A further 12 PBM-3Rs were transferred to the Royal Australian Air Force for transporting troops and cargo.

The Royal Netherlands Navy acquired 17 PBM-5A Mariners at the end of 1955 for service in Netherlands New Guinea. The PBM-5A was an amphibian with retractable landing gear. The engines were 2,100 hp (1,600 kW) Pratt & Whitney R-2800-34. After a series of crashes, the Dutch withdrew their remaining aircraft from use in December 1959.

Role flying boat
Manufacturer Glenn L. Martin Company
First flight 18 February 1939
Introduction September 1940
Retired 1964 (Uruguay)
Primary users United States Navy
United States Coast Guard
Royal Australian Air Force
Argentine Navy
Produced 1937-1949
Number built 1285
Developed into Martin P5M Marlin


General characteristics

  • Crew: Seven
  • Length: 79 ft 10 in (23.50 m)
  • Wingspan: 118 ft 0 in (36 m)
  • Height: 27 ft 6 in (5.33 m)
  • Wing area: 1,408 ft² (131 m²)
  • Empty weight: 33,175 lb (15,048 kg)
  • Loaded weight: 56,000 lb (25,425 kg)
  • Powerplant: 2 × Wright R-2600-6 14-cylinder radial engines, 1,600 hp (1,194 kW) each

Performance

  • Maximum speed: 178 kn (205 mph, 330 km/h)
  • Range: 2,600 nmi (3,000 mi, 4,800 km)
  • Service ceiling: 19,800 ft (6,040 m)
  • Rate of climb: 800 ft/min (4.1 m/s)

Armament

  • Guns: 8 × .50 in (12.7 mm) M2 Browning machine guns (two each in nose, dorsal and tail turrets, one each in blisters amidships)
  • Bombs: 4,000 lb (1,800 kg) of bombs or depth charges or 2 × Mark 13 torpedoes

End notes