Because of the sometimes long lead time between development of an aircraft and its successful acceptance into service, the US Navy has always been forced to begin thinking about the next generation of aircraft as soon as possible. Reflecting this need, the US Navy contracted with Grumman in June 1941 to begin work on a replacement for their Wildcat fighter only a few months after the first model of that plane began showing up on US Navy carriers.
The Grumman replacement for the Wildcat was the F6F-3 Hellcat. It was for all intents a much improved and larger Wildcat. Both aircraft had the short and stubby appearance that was the hallmark of the Grumman pre-Second World War fighters. The Hellcat design benefited from user input provided both by American pilots, as well as foreign users of the Wildcat who had seen combat against the Axis overseas.
The Hellcat first entered into US Navy service in January 1943, but did not see action until August that year. As the tempo of Hellcat production increased, the plane soon displaced the Wildcat with both US Navy and US Marine Corps squadrons on US Navy fleet carriers, but it was too big for the escort carriers where the Wildcat remained. The Hellcat was armed with six .50 caliber machine guns. Once engaged in combat the plane quickly demonstrated its superiority over existing Japanese fighters.
Grumman did not stop trying to improve the original F6F-3 Hellcat and a second model, designated the F6F-5, began appearing on US Navy carriers in the summer of 1944. Both types of Hellcat could carry either bombs or rockets, the latter being a late-war addition equally useful against seaborne or land targets. In total, over 12,000 units of the Hellcat series were built by the time production ended in 1945. It also saw wartime srvice with the Royal Navy, and post-war with the French and Uruguayan Navies.
The Bent Wing Fighter
A plane whose genesis began with a US Navy contract awarded in June 1938 for the building of a single prototype fighter eventually evolved into the famous Vought F4U Corsair. The first prototype of the aircraft flew in May 1940, with its trademark inverted gull wings, and reflected the company’s designers bringing together a streamlined airframe with the most powerful engine then available.
During a demonstration flight in October 1940, the prototype Corsair attained the unheard-of top speed of 404 mph for a single-engine aircraft in level flight. This did not result in the quick awarding of a production contract, as overseas combat reports indicated that any new fighter being considered had to be both armored and up-gunned, as well as having self-sealing fuel tanks. This forced a redesign of the plane that pushed back the awarding of a production contract to Vought for the Corsair until June 1941.
The first production Corsair flew in June 1942 and was designated the F4U-1. However, early problems adapting it to US Navy carrier use resulted in the aircraft being confined to operating from shore bases by the US Marine Corps. Those US Navy squadrons initially equipped with the F4U-1 and intended to serve on carriers were re-equipped with Hellcats prior to being sent into combat. Despite the aircraft initially being restricted to land bases, it racked up an impressive kill rate over its Japanese counterparts, second only to the carrier-based Hellcat.
Following the F4U-1 model, Vought also came up with other versions of the Corsair. These included the F4U-1A (not an official US Navy designation), the F4U-1C, and the F4U-1D. The ‘C’ model of the Corsair was armed with four 20mm automatic cannons for ground attack, two in each wing, rather than the six .50 caliber machine guns, three in either wing, fitted to the original F4U-1 and the improved F4U-1A model. With the ‘D’ model of the Corsair, the aircraft reverted to six .50 caliber machine guns.
The introduction of the F4U-1D model into US Navy service marked the addition of under-fuselage and under-wing attachment points to the aircraft, known as ‘hard points’ (a term that will be used hereafter in the text). These hard points could carry either ordnance (bombs and rockets), or extra fuel tanks, and were eventually fitted to previous models of the Corsair.
A night-fighter variant of the F4U-D1, designated the F4U-2 equipped with only five machine guns and a radar in its starboard wing, was first delivered to the US Navy in January 1943. It was the night fighter models of the Corsair that were the first to be approved for carrier use in early 1944 by the US Navy.
The final version of the Corsair series to see combat in the Second World War (in very small numbers) was designated the F4U-4. It was armed with six .50 caliber machine guns. Like its predecessors it came in a number of variants including the F4U-4C armed with four 20mm automatic cannon. There was also an F4U-4N night fighter, and an F4U-4P photo-reconnaissance model.
Due to high production demands for the Corsair series, the US Navy brought in both Goodyear and Brewster to build near-identical copies. The Goodyear-built version of the Vought F4U-1A was referred to as the FG-1A and the Goodyear-built version of the Vought F4U-1D was labelled the FG-1D.
There had been plans for Goodyear to build a copy of the Vought F4U-4 as the FG-4, but the end of the Second World War resulted in the cancellation of that production run. The Brewster built copy of the Vought F4U-1 was labelled the F3-A1, but never saw front-line service due to poor manufacturing and quality control.
Carrier-Based Daytime Corsairs
Due to a shortage of US Navy Hellcat fighter squadrons in late 1942, the senior leadership of the US Navy decided to rescind their ban on flying the Corsair fighter series off carriers during daylight hours. By this time, a number of design fixes had been applied to the aircraft to increase its suitability for carrier operations.
The first Corsair equipped fighter squadrons to be assigned to a US Navy carrier were not US Navy but US Marine Corps—VMF-124 was assigned to the USS Essex (CV-9) on 28 December 1944. Eventually, US Navy Corsair fighter squadrons were assigned to carriers in the last year of the war. However, the majority of US Navy fighter squadrons flew the Hellcat in 1945.
By the time the Second World War had ended, American factories had built approximately 12,000 units of the Corsair in a variety of models. The usefulness of the Corsair ensured that production continued into the early postwar years for the US Navy, where it remained a frontline carrier close-air support aircraft through the Korean War. In total, 750 units of the Corsair series would be built postwar, with production finally concluded in 1953.
The first postwar built model of the Corsair series was the F4U-5, with a night fighter version designated the F4U-5N. Another slower, but more heavily armored version of the aircraft, intended strictly for the ground attack role for the US Marine Corps, was referred to as the AU-1. All three saw action during the Korean War and accounted for a small number of enemy prop-driven planes, as well as a single jet-powered enemy fighter.
Too Late for Combat
As already mentioned, the US Navy always tried to look as far into the future as possible to figure out what types of carrier aircraft it would need. Reflecting this train of thought, two additional fighters went into production at the end of the Second World War. These included the single-engine Grumman F8F-1 Bearcat, optimized for the interceptor role, and the twin-engine Grumman F7F-1 Tigercat
The Bearcat was intended as the replacement for the Hellcat on US Navy carriers, with the first delivery of the aircraft taking place in February 1945. However, squadrons equipped with the Bearcat would not see combat with the US Navy or US Marine Corps during the Second World War.
Despite the impressive performance of the Bearcat, prop-driven fighters were quickly being replaced by jet-powered aircraft in the immediate postwar era, and it was pulled from both the US Navy and US Marine Corps frontline inventory before the Korean War. A total of 1,265 units of the Bearcat were constructed out of an original order in October 1944 for 2,023 units, the rest having been cancelled.
The first production units of the F7F-1 Tigercat were handed over to the US Navy in April 1944. A two-seat night-fighting model of the Tigercat was designated as the F7F-2N and was delivered in October 1944. It was followed by the delivery of another single-seat model, labelled the F7F-3, beginning in March 1945.
Testing conducted by the US Navy in April 1945 showed that the Tigercat was unsuitable for carrier use due to a number of design issues. The US Navy therefore transferred all of them to the US Marine Corps for the land-based close-air support role, however, it showed up in squadron service too late to see combat during the Second World War. The aircraft saw action during the early part of the Korean War with the US Marine Corps. The enemy introduction of jet-powered fighters resulted in the Tigercat being withdrawn from combat use in Korea in 1952. It lasted in US Marine Corps service until 1954. A total of 364 units of the Tigercat series were built.
The Last Scout-Bombers
Ordered by the US Navy in November 1940 from Curtiss-Wright was a monoplane scout-bomber, designated the SB2C-1, which the company named ‘Helldiver’. It was intended to replace their earlier Curtiss SBC-3 and SBC-4 scout-bombers, both being biplanes, also named Helldivers. The SB2C-1 was also ordered by the US Army Air Forces, who had been very impressed by the German Air Force employment of dive bombers during their attack on Poland in September 1939.
The SB2C-1 Helldiver did not enter into production until mid-1942 due a number of design problems and production bottlenecks. Only 200 units of the SB2C-1 were built for the US Navy and none saw combat. An improved version, labelled the SB2C-1C, first saw combat with the US Navy in late 1943, with a total of 778 units built. The SB2C-3 variant had a more powerful engine fitted and 1,112 units were constructed. Fitted with a radar, the SB2C-3 was designated the SB2C-3E. The letter ‘E’ in the aircraft’s designation stood for electronics.
Also assembled were 2,045 units of a modified version of the SB2C-1, known as the SB2C-4. It was fitted with underwing hard points for air-to-surface rockets or bombs. Equipped with a radar unit the plane became the SB2C-4E. An upgraded version of the SB2C-4 without a radar was designated the SB2C-5; a total of 970 units of the SB2C-5 were built, with another 2,500 units cancelled due to the end of the Second World War. In total, Curtiss-Wright built 5,516 units of the SB2C series.
Two Canadian firms built copies of the Curtiss-Wright SB2C-1, SB2C-3, and SB2C-4E Helldivers. These included Fairchild-Canada and Canadian Car and Foundry. The 300 copies of the SB2C-1, SB2C-3, and SB2C-4E constructed by Fairchild-Canada were respectively labelled the SBF-1, SBF-3, and SBF-4E. The 860 copies built by Canadian Car and Foundry were respectively labelled the SBW-1, SBW-1B, SBW-3, and SBW-4E. Canadian Car and Foundry also built a version of the SB2C-5 that was referred to as the SBW-5.
Combat service of the SB2C series of Helldivers with the US Navy was extremely mixed, with many feeling that it was a badly-designed aircraft that reflected poorly on its designer and builder. The issues, both real and perceived, that bedeviled the SB2C series badly sullied the reputation of Curtiss-Wright and contributed to it being the last aircraft acquired by the US Navy from the firm.
Most of those in the US Navy who had to deal with the SB2C series during the Second World War felt that its predecessor, the Douglas SBD Dauntless, was a better aircraft, despite the Curtiss-Wright SB2-C being superior in its operational parameters, except in range. A total of thirty US Navy and twenty-five US Marine Corps squadrons flew the aircraft during the Second World War. The US Marine Corps inventory of SB2C series aircraft were primarily land-based.
Another scout-bomber that was approved for production by the US Navy prior to Pearl Harbor, but which did not begin coming off the factory floor until 1943, was the Brewster SB2A Buccaneer. It was the Brewster replacement for their earlier SBN-1. It was not a success in the scout-bomber role and was quickly transferred to training duties. The Royal Navy, which received the SB2A under Lend-Lease, also concluded that it was unfit for combat, and confined it to secondary duties. Brewster built a total of 771 units of the SB2A.
The US Navy’s Last Torpedo-Bomber
The US Navy’s wartime-built torpedo bomber was the Grumman TBF-1 Avenger. It was the intended replacement for the pre-war designed Douglas TBD-1 Devastator. The origins of the TBF-1 began in early 1940, when the US Navy asked both Vought and Grumman for a state-of-the-art torpedo bomber. Vought won the competition, but their plane, designated the TBY Sea Wolf by the US Navy, was besieged by a host of design and production problems that resulted in it showing up in service late in the Second World War, and never seeing frontline combat service.
By default, the TBF-1 torpedo bomber filled in for the TBY during the conflict, with the first delivery taking place in January 1942. A follow-on model, designated the TBF-1C, had larger fuel tanks to increase the aircraft range, and two wing-mounted, forward-firing .50 caliber machine guns, in place of the single forward-firing fuselage-mounted .30 caliber in the original model of the aircraft. The aircraft was powered by a 1,700 hp engine.
There were additional versions of the TBF-1 converted for roles other than torpedo-bomber, with a letter or letters added to the end of their aircraft designation to identify their new jobs. These new assignments included radar equipped units labelled the TBF-1D and TBF-1CD. Those modified for photo-reconnaissance work were referred to as TBF-1P and TBF-1CP. A model specially equipped for poor weather conditions was designated the TBF-1J. In total, Grumman built 1,526 units of the TBF-1 series, of which 465 units went to America’s wartime Allies.
Due to the high wartime demand for the TBF series, it was decided to have General Motors build copies of the aircraft. The US Navy designated the General Motors copy of the Grumman TBF-1 model as the TBM-1 and the Grumman TBF-1C model as the TBM-1C. These aircraft started coming off the assembly line in September 1942. In total, General Motors constructed 7,546 units of the Grumman designed TBF-1 and TBF-1C, which, like the Grumman-built product, was also modified for other roles and assigned additional letter designations to define their purpose.
The last model of the Grumman designed TBF series of torpedo-bombers was a General Motors development of the aircraft, with a more powerful 1,900 hp engine and strengthened wings to carry more ordnance, and electronics, such as radar units. It was designated the TBM-3 and the initial delivery of the model began in April 1944. Of the 4,011 units of the TBM-3 built, many served in a variety of roles, like earlier models of the aircraft, and were labelled with additional letter designations. Two hundred and twenty-two units went to the Royal Navy.
Scout-Bomber and Torpedo-Bomber Demise
With the introduction of the F6F Hellcat and the F4U Corsair into service, the US Navy now had carrier fighters that were capable of hauling into combat an ordnance load that almost equalled what the existing scout-bombers and torpedo-bombers could tote. Unlike the bombers that were vulnerable to enemy fighters both before and after delivering their ordnance, the new fighters could defend themselves. This was another reason for the growing numbers of fighters on late-war US Navy carriers taking the place of scout-bombers and torpedo-bombers.
Seaplane Patrol Bombers
Besides the very capable twin-engine pre-Second World War Consolidated PBY series and the Martin PBM series, built in large numbers during the Second World War, the US Navy ordered from Consolidated in 1939 six test units of a four-engine seaplane designated the PB2Y-2. Testing went well and an improved production version labelled the PB2Y-3 began showing up in US Navy service in early 1942. Eventually, Martin built 210 units of the PBY-3 Coronado series. Most were upgraded in wartime to the PBY-5 standard.
The Martin Company came up with a very large four-engine seaplane ordered by the US Navy in August 1938. However, the first flight of the prototype, designated the XPB2M-1 Mars, did not take place until July 1942. By that time, the US Navy realized the aircraft’s design was not up to wartime standards as a patrol bomber. However, in January 1945, it ordered twenty transport versions of the plane, labelled the JRM Mars, with the first being delivered in June 1945. With the war ending in September 1945, the order was cut back to only five units.
Land-Based Patrol Bombers
Due to the high demand for maritime patrol bombers during the Second World War, the US Navy took into service a number of land-based multi-engine aircraft. This upended the 1931 agreement between the US Army Air Corps and the US Navy, restricting the latter to employing only seaplanes and ship-based aircraft.
A twin-engine aircraft originally designed as a pre-war passenger plane by Lockheed and modified into a maritime patrol bomber was designated the PBO-1. Twenty were acquired by the US Navy and a squadron based in Newfoundland sank a single German submarine in March 1942.
The PBO-1 was followed into service by 1,600 units of a similar model, also built by Lockheed, designated the PV-1 Ventura. A large number of the units of the PV-1 went to America’s wartime allies. A follow-on model for the US Navy was referred to as the PV-2 Harpoon, with 535 units built, with delivery beginning in March 1944. Most saw service in the Pacific Theater of Operation (PTO) during the Second World War.
For long-range maritime patrol bomber duties the US Navy decided that land-based four-engine aircraft were superior to four-engine seaplanes. This came about due to the successful use of the Consolidated four-engine B-24 Liberator heavy bomber in that role by the RAF Coastal Command. The US Navy’s request for an allotment of modified Liberators was approved in July 1942, and the aircraft was labelled the PB4Y-1
A few PB4Y-1s were later configured for the long-range reconnaissance role and received the designation PB4Y-1P. Approximately 1,000 units of the PB4Y-1 were taken into US Navy service during the Second World War. Its usefulness resulted in it being employed in the immediate postwar era.
In May 1943, the US Navy ordered from Consolidated 739 units of a version of the Liberator designed specifically for naval use, which they designated the PB4-Y Privateer. However, very few made it into service before the Second World War ended. The aircraft remained in US Navy service until 1954. In March 1943, Consolidated had merged with the Vultee Aircraft Company and eventually became known as Convair.
Other aircraft originally intended for use by the US Army Air Forces during the Second World War were acquired by the US Navy during the conflict to perform different jobs. These included various models of the twin-engine North American B-25 Mitchell medium bomber, of which initial delivery began in January 1943.
The US Navy assigned its inventory of 706 B-25 Mitchell medium bombers the designation code PBJ-1, and kept the US Army Air Forces model letter prefixes, as the planes were not modified in any way. Rather than being employed as maritime patrol bombers, they were all transferred to the US Marine Corps. They employed them as rocket-equipped attack aircraft in the PTO, generally going after Japanese shipping, beginning in March 1944.
Another US Army Air Forces medium bomber adopted by the US Navy during the Second World War was an early version of the Martin B-26 Marauder that had been modified in 1943 as an unarmed target tug, and eventually designated the TB-26B. In US Navy service it became the JM-1. Another unarmed target tug version of a later production B-26 was labelled the TB-26G. It became the JM-2 in US Navy service. Both aircraft were employed as target tugs and utility planes by the US Navy, with a total of 272 units being taken into the inventory.
Also picked up for service by the US Navy during the Second World War were several pre-war designed multi-engine aircraft originally designed for the civilian passenger plane industry, the best known being the militarized version of the twin-engine Douglas DC-3. It was designated the C-47 Skytrain by the US Army Air Forces and in US Navy service the aircraft was referred to as the R4D.
Another militarized prewar designed twin-engine passenger plane acquired by the US Navy was the Curtiss C-46A Commando, designated as the R5C1, all of which went to the US Marine Corps. A four-engine pre-war-designed passenger plane acquired by the US Navy from the US Army Air Forces during the Second World War was the Douglas C-54 Skymaster. In US Navy service it was labelled the R5D series and a total of 183 units of various versions were taken into the inventory.
The helicopter, which appeared at the tail end of the Second World War, was of little interest to the US Navy at that time. Rather than be bothered with it, they assigned helicopter development to the US Coast Guard, which was attached to the US Navy during the Second World War. Sikorsky provided the US Coast Guard several helicopter models, designated by the US Navy as the HNS-1, the HOS-1, and the HO2S-1. It was only after the Second World War, as helicopter technology progressed, that the US Navy began to see the usefulness of this new flying machine and took over its development.