Martin PBM-5 Mariner
With their previous P3M design reaching the end of its service life and to supplement the shorter-ranged PBY Catalina, the Martin Company in 1937 proposed a twin-engined flying boat to the US Navy which would be larger and longer-ranged than the PBY. The Navy agreed, ordering a prototype XPBM-1 Mariner in June 1937, to be supplemented by at least 20 more PBM-1s if testing was successful.
To give the PBM a heavy payload, Martin designed an aircraft with a deep, slab-sided fuselage somewhat similar to Consolidated’s B-24 Liberator, using a gull wing to keep the engines out of water spray, with retractable wing floats similar to the PBY’s. Bombs were carried in the engine nacelles. Emphasis was given to crew comfort: since the PBMs would be undertaking long patrol missions, up to 12 hours long in some cases, crews were given bunks, heating, a refrigerator and a galley, a big improvement over the often-uncomfortable PBY. To ensure clean aerodynamics, it was designed with a twin tail. The design was revolutionary enough that Martin was worried about its performance, and a quarter-scale version, the Martin 162A Tadpole Clipper, was flown in December 1937. The concept was proven and the Navy duly ordered the Mariner placed into full production as the PBM-1 in the same month.
As the XPBM-1 began testing in February 1939, however, Martin found that the Mariner’s design did have trouble. The Tadpole Clipper had been single-engined, and so it had not experienced engine problems of the twin-engined Mariner, which suffered from both aerodynamic and hydrodynamic problems. The engines’ propensity for catching fire and then exploding was something the Mariner was never quite able to overcome, but Martin was able to cure the other problems by a slight hull redesign and canting the tailplane upwards, which in turn required the endplate tailfins to be canted inwards, giving the Mariner a unique appearance. The PBM-1 reached the fleet in September 1940. It was soon supplemented by the PBM-3 (the XPBM-2 being a failed experimental carrier-launched version), which added three feet to the fuselage to further improve handling, less complicated non-retracting wing floats, and radar in a fairing above the fuselage.
The early problems with the Mariner, not to mention its higher cost, likely ensured that it would never reached the same numbers or popularity as its rival, the Catalina. However, the Mariner was far more comfortable, and its easy handling endeared it to crews on long-haul missions, especially those who had flown the tempramental B-24. While the PBM-3 and PBM-5 series used powered turrets, the PBM-3C stripped these down for manual guns, to save weight for even further increased range.
PBMs would serve extensively in World War II, even before the United States formally entered the war: in early 1941, PBM-3s would participate in Neutrality Patrol missions in the western Atlantic, radioing positions of sighted U-boats to British Royal Navy and Royal Canadian Navy destroyers and corvettes. Once war was formally declared, PBMs began hunting U-boats themselves, sinking their first in June 1942. Mariners would only sink ten U-boats during the war, but this does not reflect how many German submarines they forced away from convoys or discouraged by their presence. Mariners were also used in the Pacific, though here they did more than hunt Japanese I-boats; they were used heavily in the search and rescue role, and as bombers attacking isolated Japanese garrisons bypassed by Allied forces.
If the Mariner was never produced in numbers or had the popularity of the PBY, it would last longer in service, being one of the few World War II-era designs to remain in US Navy service. PBM-5s would be used during the Korean War as patrol and SAR aircraft, and were used in Operation Highjump, the Navy’s Antarctic research project. Still others served as the backbone of US Coast Guard rescue units in the 1950s, and others were exported to Argentina, Australia, the Netherlands, and Uruguay, the latter being the last operator of the Mariner in 1964. By this time, the US Navy had also retired its aircraft, replacing them with the P2V Neptune and the P5M Marlin, Martin’s purpose-built successor to the Mariner. Of 1285 PBMs built, only one today survives at the Pima Air and Space Museum...
...and this is it. Built as Bureau Number 122071, this is a PBM-5A amphibian and one of the last Mariners to be built. It was delivered to VP-33 at NAS Norfolk, Virginia in 1948, but only remained in active service for two years. In 1950, it was transferred to the US Naval Academy at Annapolis, Maryland for initial crew training for cadets, then retired in 1953. Sold off as surplus in 1958, it was acquired by private owners until 1972. At that point, it was realized that 122071 was the only intact Mariner left anywhere, and it was purchased by the Smithsonian for eventual display at the Air and Space Museum. Very quickly, the aircraft was loaned to the Pima Air and Space Museum, where it could be restored and put on display; the NASM simply did not have the room.
For awhile, 122071 was displayed outside, but the precious nature of this aircraft meant that it was moved inside as soon as possible. It is kept in excellent condition, and wears the overall midnight blue scheme of late 1940s-early 1950s US Navy aircraft.
Dad had always been a fan of the Mariner, and knew a gentleman here in Montana who had flown them during World War II. It was fascinating to see the last one left.
Martin PBM-5 Mariner
With their previous P3M design reaching the end of its service life and to supplement the shorter-ranged PBY Catalina, the Martin Company in 1937 proposed a twin-engined flying boat to the US Navy which would be larger and longer-ranged than the PBY. The Navy agreed, ordering a prototype XPBM-1 Mariner in June 1937, to be supplemented by at least 20 more PBM-1s if testing was successful.
To give the PBM a heavy payload, Martin designed an aircraft with a deep, slab-sided fuselage somewhat similar to Consolidated’s B-24 Liberator, using a gull wing to keep the engines out of water spray, with retractable wing floats similar to the PBY’s. Bombs were carried in the engine nacelles. Emphasis was given to crew comfort: since the PBMs would be undertaking long patrol missions, up to 12 hours long in some cases, crews were given bunks, heating, a refrigerator and a galley, a big improvement over the often-uncomfortable PBY. To ensure clean aerodynamics, it was designed with a twin tail. The design was revolutionary enough that Martin was worried about its performance, and a quarter-scale version, the Martin 162A Tadpole Clipper, was flown in December 1937. The concept was proven and the Navy duly ordered the Mariner placed into full production as the PBM-1 in the same month.
As the XPBM-1 began testing in February 1939, however, Martin found that the Mariner’s design did have trouble. The Tadpole Clipper had been single-engined, and so it had not experienced engine problems of the twin-engined Mariner, which suffered from both aerodynamic and hydrodynamic problems. The engines’ propensity for catching fire and then exploding was something the Mariner was never quite able to overcome, but Martin was able to cure the other problems by a slight hull redesign and canting the tailplane upwards, which in turn required the endplate tailfins to be canted inwards, giving the Mariner a unique appearance. The PBM-1 reached the fleet in September 1940. It was soon supplemented by the PBM-3 (the XPBM-2 being a failed experimental carrier-launched version), which added three feet to the fuselage to further improve handling, less complicated non-retracting wing floats, and radar in a fairing above the fuselage.
The early problems with the Mariner, not to mention its higher cost, likely ensured that it would never reached the same numbers or popularity as its rival, the Catalina. However, the Mariner was far more comfortable, and its easy handling endeared it to crews on long-haul missions, especially those who had flown the tempramental B-24. While the PBM-3 and PBM-5 series used powered turrets, the PBM-3C stripped these down for manual guns, to save weight for even further increased range.
PBMs would serve extensively in World War II, even before the United States formally entered the war: in early 1941, PBM-3s would participate in Neutrality Patrol missions in the western Atlantic, radioing positions of sighted U-boats to British Royal Navy and Royal Canadian Navy destroyers and corvettes. Once war was formally declared, PBMs began hunting U-boats themselves, sinking their first in June 1942. Mariners would only sink ten U-boats during the war, but this does not reflect how many German submarines they forced away from convoys or discouraged by their presence. Mariners were also used in the Pacific, though here they did more than hunt Japanese I-boats; they were used heavily in the search and rescue role, and as bombers attacking isolated Japanese garrisons bypassed by Allied forces.
If the Mariner was never produced in numbers or had the popularity of the PBY, it would last longer in service, being one of the few World War II-era designs to remain in US Navy service. PBM-5s would be used during the Korean War as patrol and SAR aircraft, and were used in Operation Highjump, the Navy’s Antarctic research project. Still others served as the backbone of US Coast Guard rescue units in the 1950s, and others were exported to Argentina, Australia, the Netherlands, and Uruguay, the latter being the last operator of the Mariner in 1964. By this time, the US Navy had also retired its aircraft, replacing them with the P2V Neptune and the P5M Marlin, Martin’s purpose-built successor to the Mariner. Of 1285 PBMs built, only one today survives at the Pima Air and Space Museum...
...and this is it. Built as Bureau Number 122071, this is a PBM-5A amphibian and one of the last Mariners to be built. It was delivered to VP-33 at NAS Norfolk, Virginia in 1948, but only remained in active service for two years. In 1950, it was transferred to the US Naval Academy at Annapolis, Maryland for initial crew training for cadets, then retired in 1953. Sold off as surplus in 1958, it was acquired by private owners until 1972. At that point, it was realized that 122071 was the only intact Mariner left anywhere, and it was purchased by the Smithsonian for eventual display at the Air and Space Museum. Very quickly, the aircraft was loaned to the Pima Air and Space Museum, where it could be restored and put on display; the NASM simply did not have the room.
For awhile, 122071 was displayed outside, but the precious nature of this aircraft meant that it was moved inside as soon as possible. It is kept in excellent condition, and wears the overall midnight blue scheme of late 1940s-early 1950s US Navy aircraft.
Dad had always been a fan of the Mariner, and knew a gentleman here in Montana who had flown them during World War II. It was fascinating to see the last one left.