POWER PLANT: One Pratt & Whitney R-2800-6 “Double Wasp” radial engine, rated at 2,000 hp
PERFORMANCE: 306 mph
COMMENT: The original design was not by Consolidated Aircraft, but rather by Vought, who designed the XTBU-1 “Sea Wolf” to a 1939 US Navy requirement. The first prototype flew two weeks after Pearl Harbor. Its performance was deemed superior to the Grumman TBF-1 “Avenger” and the Navy placed an order for 1,000 aircraft.
Several unfortunate incidents intervened; the prototype was damaged in a rough arrested landing trial, and when repaired a month later was again damaged in a collision with a training aircraft. Once repaired again, the prototype was accepted by the Navy. However, by this time Vought was heavily overcommitted to other contracts, especially for the F4U “Corsair” fighter, and had no production capacity. It was arranged that Consolidated Vultee would produce the aircraft as the TBY-1, but this had to wait until the new production facility in Allentown, Pennsylvania was complete, which took until late 1943.
The production TBY-2’s were radar-equipped, with a radome under the right-hand wing. The first aircraft flew on 20 August 1944. By this time though, the Grumman TBF-3 “Avenger” equipped every torpedo squadron in the Navy, and there was no need for the “Sea Wolf”; in addition, numerous small problems delayed entry into service so the aircraft never saw combat. Orders for 1,000 aircraft were cancelled after production started, and the 180 built were used for training only (Ref.: 24).
POWER PLANT: One Wright R-2600-20 “Twin Cyclone” radial engine, rated at 1,900 hp
PERFORMANCE: 276 mph at 16,500 ft
COMMENT: By 1943, Grumman began to slowly phase out production of the TBF “Avenger” to produce Grumman F6F “Hellcat” fighters, and the Eastern Aircraft Division of General Motors took over production, with these aircraft being designated TBM. The Eastern Aircraft plant was located in Ewing, NJ. Grumman delivered a TBF-1, held together with sheet metal screws, so that the automotive engineers could disassemble it, a part at a time, and redesign the aircraft for automotive style production. This aircraft was known as the “P-K Avenger” (P-K = Parker-Kalon, manufacturer of sheet metal screws). Starting in mid-1944, the TBM-3 began production with a more powerful power plant and wing hard points for drop tanks and rockets. The dash-3 was the most numerous of the “Avengers” with about 4,664 produced. However, most of the “Avengers” in service were dash-1s until near the end of the war in 1945.
Besides the traditional surface role (torpedoing surface ships), “Avengers” claimed about 30 submarine kills. They were one of the most effective sub-killers in the Pacific theatre, as well as in the Atlantic, when escort carriers were finally available to escort Allied convoys. There, the “Avengers” contributed to the warding off of German submarines while providing air cover for the convoys (Ref.: 24).
POWER PLANT: One Pratt & Whitney R-2800-2 “Double Wasp 2” radial engine, rated at 2,000 hp
PERFORMANCE: 306 mph
COMMENT: The Chance-Vought XTBU-1 “Sea Wolf” was a torpedo bomber designed as a rival to the Grumman TBF “Avenger”, and that entered production as the Consolidated TBY-“Sea Wolf”.
In October 1939 the US Navy issued a request for proposals for a new torpedo bomber to the US aircraft industry. The new aircraft was to carry a crew of three, have a top speed of 300mph, be able to carry one torpedo or three 500lb bombs internally, have self-sealing fuel tanks and armor and a powered dorsal gun turret.
A number of companies submitted designs to satisfy this specification, but only Grumman and Chance-Vought received orders to build prototypes. The Chance-Vought design resembled a less ‘chunky’ version of the Grumman TBF “Avenger”, with a longer greenhouse canopy, although it took up more space with its wings folded than the Grumman design. The prototype was powered by a Pratt & Whitney R-2800-6 engine for its first flight, then by an R-2800-2. One unusual feature was a single control that lowered undercarriage and flaps and set propeller pitch and fuel mixture ready for landing.
Chance-Vought received an order on April 1940, and the prototype made its first flight on December 1941. By this time it was already almost too late. Grumman had received a production order for the TBF-1 “Avenger” in December 1940, and the first prototype made its maiden flight in August 1941. The Japanese attack on Pearl Harbor and the resulting US entry into the WW II meant that the need for a new torpedo bomber was suddenly very urgent. The XTBU-1 reached NAS Anacostia for trials in March 1942, but despite proving to be 30 mph faster than the “Avenger” it was not put into production until the following year.
The XTBU-1 was armed with one fixed forward firing 0.50in gun in the engine cowling, one 0.50in gun in the power operated dorsal turret and one 0.30in gun mounted in the ‘stinger’ or ventral tunnel position (the same defensive layout as the original “Avenger”).
By 1942 Chance Vought was building fighter aircraft, most famously the F4U “Corsair”. When the Navy finally decided to put their torpedo-bomber into production in 1943 they had to find an alternative manufacturer, and so in September 1943 Consolidated Vultee received an order to produce 1,100 aircraft with the new designation TBY-2 “Sea Wolf” (Ref.: 23, 24).
POWER PLANT: One Wright R-2600-8 radial engine, rated at 1,700 hp
PERFORMANCE: 275 mph at 12,000 ft
COMMENT: Grumman TBF “Avenger” in mid-1942 Grumman’s first torpedo bomber was the heaviest single-engine aircraft of World War II, and only the USAAF’s Republic P-47 “Thunderbolt” came close to equaling it in maximum loaded weight among all single-engine fighters, being only some 181 kg lighter than the TBF, by the end of World War II. To ease carrier storage concerns, simultaneously with the Grumman F4F-4 “Wildcat” carrier-borne fighter, Grumman designed the “Avenger” to also use the new “Sto-Wing” patented compound angle wing-folding mechanism, intended to maximize storage space on an aircraft carrier; in addition to the “Wildcat” and “Avenger”, the “Wildcat’s” replacement, the Grumman F6F “Hellcat” also employed this mechanism as well. There were three crew members: pilot, turret gunner and radioman/bombardier/ventral gunner. One .30 caliber machine gun was mounted in the nose, a .50 caliber (12.7 mm) gun was mounted right next to the turret gunner’s head in a rear-facing electrically powered turret, and a single .30 caliber hand-fired machine gun mounted ventrally (under the tail), which was used to defend against enemy fighters attacking from below and to the rear. This gun was fired by the radioman/bombardier while standing up and bending over in the belly of the tail section, though he usually sat on a folding bench facing forward to operate the radio and to sight in bombing runs. The TBF-1C model dispensed with the nose-mounted gun for one .50 caliber gun in each wing per pilots’ requests for better forward firepower and increased strafing ability. There was only one set of controls on the aircraft, and no access to the pilot’s position from the rest of the aircraft. The radio equipment was massive, especially by today’s standards, and filled the length of the well-framed “greenhouse” canopy to the rear of the pilot. The “Avenger” had a large bomb bay, allowing for one Bliss-Leavitt “Mark 13” torpedo, a single 907 kg bomb, or up to four 227 kg bombs. The aircraft had overall ruggedness and stability, and pilots say it flew like a truck, for better or worse. With its good radio facilities, docile handling, and long range, the Grumman Avenger also made an ideal command aircraft for Commanders Air Group (CAGs). With a 30,000 ft ceiling and a fully loaded range of 1,610 km, it was better than any previous American torpedo bomber, and better than its Japanese counterpart, the obsolete Nakajima B5N “Kate”. Later “Avenger” models carried radar equipment for the ASW and AEW roles. Escort carriers sailors referred to the TBF as the “turkey” because of its size and maneuverability in comparison to the F4F “Wildcat” fighters in CVE air groups.
A total of 2,290 Grumman TBF “Avengers” have been produced until early 1944 when the production switched over to General Motors Company to produce 4,664 additional TBM “Avengers” (Ref.: 24).
POWER PLANT: One Pratt & Whitney R-1830-56 radial engine, rated at 1,350 hp
PERFORMANCE: 320 mph
COMMENT: Grumman’s F4F “Wildcat” production ceased in early 1943 to make way for the newer F6F “Hellcat”, but General Motors/Eastern Aircraft continued producing “Wildcats” for both U.S. Navy and (British) Fleet Air Arm use. At first, General Motors produced the FM-1 (identical to the F4F-4, but with four guns). Production later switched to the improved FM-2 (based on Grumman’s XF4F-8 prototype, informally known as the “Wilder Wildcat”) optimized for small-carrier operations, with a more powerful engine, and a taller tail to cope with the increased torque.
From 1943 onward, “Wildcats” equipped with bomb racks were primarily assigned to escort carriers for use against submarines and attacking ground targets, though they would also continue to score kills against Japanese fighters, bombers and kamikaze aircraft. Larger fighters such as the “Hellcat” and the Vought F4U “Corsair” and dedicated dive bombers were needed aboard fleet carriers, and the “Wildcat’s” slower landing speed and its size made it more suitable for shorter flight decks of escort carriers.
General Motors / Eastern Aircraft produced 5,280 FM-1 and FM-2 variants out of total production of 7,860 “Wildcats” (Ref.: 24).
POWER PLANT: One Ranger XV-770-8-8 inline air-cooled engine, rated at 600 hp
PERFORMANCE: 172 mph at 8,100 ft
COMMENT: The Curtiss SO3C “Seamew” was developed by the Curtiss-Wright Corporation as a replacement for the Curtiss SOC “Seagull” as the US Navy’s’s standard floatplane scout. Curtiss named the SO3C the “Seamew” but in 1941 the US Navy began calling it by the name “Seagull”, the same name as the aircraft it replaced (the Curtiss SOC a biplane type), causing some confusion. The British Royal Navy kept the Curtiss name “Seamew” for the SO3C that they ordered. One of the US Navy’s main design requirements was that the SOC “Seagull’s” replacement had to be able to operate both from ocean vessels with a single center float and from land bases with the float replaced by a wheeled landing gear.
From the time it entered service the SO3C suffered two serious flaws: inflight stability problems and problems with the unique Ranger air-cooled, inverted V-shaped inline engine. The stability problem was mostly resolved with the introduction of upturned wingtips and a larger rear tail surface that extended over the rear observer’s cockpit. The additional tail surface was attached to the rear observer’s sliding canopy and pilots claimed there were still stability problems when the canopy was open. The canopy was often open because the aircraft’s main role was spotting. While the inflight stability problem was eventually addressed (although not fully solved), the Ranger XV-770 engine proved a dismal failure even after many attempted modifications. Poor flight performance and a poor maintenance record led to the SO3C being withdrawn from US Navy first line units by 1944. The older biplane Curtiss SOC “Seagull” was taken from stateside training units and restored to first-line service on many US Navy warships until the end of World War II. In total 795 Curtiss SO3C “Seamew’s”have been built (Ref.: 24).
POWER PLANT: One Pratt & Whitney R-2800-34W “Double Wasp” radial engine, rated at 2,300 hp
PERFORMANCE: 421 mph at 19,700 ft
COMMENT: The Grumman F8F “Bearcat” concept began during a meeting between Battle of Midway veteran Grumman F4F “Wildcat” pilots and Grumman authorities on June 1942. At the meeting, Lieutenant Commander J. Thatch emphasized one of the most important requirements in a good fighter plane was “climb rate”.
Climb performance is strongly related to the power-to weight ratio, and is maximized by wrapping the smallest and lightest possible airframe around the most powerful available engine. Another goal was that the new fighter – Grumman’s design designation for the aircraft was G-58 – should be able to operate from escort carries, which were then limited to the obsolescent F4F “Wildcat” as the Grumman F6F “Hellcat” was too large and heavy. A small, lightweight aircraft would make this possible. After intensively analyzing carrier warfare in the Pacific Theatre of Operation for a year and a half, Grumman began development of the G-58 “Bearcat” in late 1943.
In 1943, Grumman was in the process of introducing the F6F Hellcat, powered by the Pratt & Whitney R-2800 engine which provided 2,000 horsepower. The R-2800 was the most powerful American engine available at that time, so it would be retained for the G-58. This meant that improved performance would have to come from a lighter airframe.
To meet this goal, the Bearcat’s fuselage was about 1.5 m shorter than the Hellcat, and was cut down vertically behind the cockpit area. This allowed the use of a bubble canopy, the first to be fit to a US Navy fighter. The vertical stabilizer was the same height as the Hellcat’s, but increased aspect ratio, giving it a thinner look. Similarly, the main wing had the same span, but having lower thickness, especially at the root. Structurally the fuselage was strengthened and armor protection was provided for the pilot, engine and oil cooler. Compared to the “Hellcat”, the “Bearcat” was 20% lighter, had a 30% better rate of climb and was 50 mph (80 km/h) faster.
The Navy placed a production contract for 2,023 aircraft based on the second prototype on 6 October 1944. On February 1945 they awarded another contract for 1,876 slightly modified aircraft from General Motors, given the designation F3M-1. These differed primarily in having the R-2800-34W engine and a small increase in fuel capacity.
Deliveries from Grumman began on May 1945. The end of the war led to the Grumman order being reduced to 770 examples, and the GM contract being cancelled outright. An additional order was placed for 126 F8F-1B’s replacing the .50 cal machine guns with the 20 mm M2 cannon, the US version of the widely used Hispano-Suiza HS.404. The F8F prototypes were ordered in November 1943 and first flew on 21 August 1944, a mere nine months later. The first production aircraft was delivered in February 1945 and the first squadron, VF-19, embarked to CV 16 “Lexington”, was operational by May 1945, but WW II was over before the aircraft saw combat service (Ref.: 24).
POWER PLANT: One Westinghouse 24C turbojet engine, rated at 1,360 kp
PERFORMANCE: 535 mph
COMMENT: The design for a fast carrier-based jet fighter was put forward by Grumman Company in November 1944. This small and aerodynamic clean cantilever-winged fighter was to be armed with either four 20mm cannon or six 0.5 in machine guns across the nose. The wings were not of folding type. The aircraft was to be powered by a single Westinghouse 24C turbojet engine delivering app. 1,300 kp thrust, but was still under development. It was the first jet fighter project of Grumman and it is not clear why this promising project was not pursued. However, after WW II the general design influenced the development of the Grumman F9F “Panther”, the Company’s first turbojet engine powered fighter showing better performance compared to the McDonnell FD-1 “ Phantom”, the US Navy’s first “pure” turbojet fighter.
POWER PLANT: Two Westinghouse J30-WE-20 turbojet engines, rated at 725 kp each
PERFORMANCE: 479 mph at sea level
COMMENT: In early 1943, aviation officials at the United States Navy were impressed with McDonnell’s audacious XP-67 “Bat” project. McDonnell was invited by the Navy to cooperate in the development of a shipboard jet fighter, using an engine from the turbojets under development by Westinghouse Electric Corporation. Three prototypes were ordered on August 1943 and the designation XFD-1 was assigned. Under the 1922 United States Navy aircraft designation system, the letter “D” before the dash designated the aircraft’s manufacturer. The Douglas Aircraft Company had previously been assigned this letter, but the USN elected to reassign it to McDonnell because Douglas had not provided any fighters for Navy service in years.
McDonnell engineers evaluated a number of engine combinations, varying from eight 24 cm diameter engines down to two engines of 48 cm diameter. The final design used the two 48 cm engines after it was found to be the lightest and simplest configuration. The engines were buried in the wing root to keep intake and exhaust ducts short, offering greater aerodynamic efficiency than underwing nacelles and the engines were angled slightly outwards to protect the fuselage from the hot exhaust blast. Placement of the engines in the middle of the airframe allowed the cockpit with its bubble-style canopy to be placed ahead of the wing, granting the pilot excellent visibility in all directions. This engine location also freed up space under the nose, allowing designers to use tricycle gear, thereby elevating the engine exhaust path and reducing the risk that the hot blast would damage the aircraft carrier deck. The construction methods and aerodynamic design of the “Phantom”, as the aircraft was assigned, were fairly conventional for the time; the aircraft had unswept folding wings. Adapting a jet to carrier use was a much greater challenge than producing a land-based fighter because of slower landing and takeoff speeds required on a small carrier deck. When the first XFD-1was completed in January 1945, only one Westinghouse was available for installation. Ground runs and taxi tests were conducted with the single engine, and such was the confidence in the aircraft that the first flight on 26 January 1945 was made with only the one turbojet engine. During flight tests, the “Phantom” became the first naval aircraft to exceed 500 mph. With successful completion of tests, a production contract was awarded on March 1945 for 100 FD-1 aircraft. With the end of the war, the “Phantom” production contract was reduced to 30 aircraft, but was soon increased back to 60.
The first prototype was lost in a fatal crash on November 1945, but the second and final “Phantom” prototype was completed early the next year and became the first purely jet-powered aircraft to operate from an American aircraft carrier, completing four successful takeoffs and landings on 21 July 1946, from USS CV-42 “Franklin D. Roosevelt”. At the time, she was the largest carrier serving with the U.S. Navy, allowing the aircraft to take off without assistance from a catapult (Ref. 24).
POWER PLANT: Two Wright XR-1820-40/41 “Cyclone” radial engines, rated at 1,200 hp each
PERFORMANCE: 380 mph at 16,500 ft
COMMENT: In 1938 Grumman presented a proposal to the U. S. Navy for a twin engine carrier based aircraft, unlike any other fighter aircraft that had ever been considered. The design was for a light weight fighter powered by two 1,200 hp Wright R-1820 engines, with propellers geared to rotate in opposite directions to cancel out the effects of each engine’s torque, promising high-speed, and an outstanding rate of climb. Designated XF5F-1 “Skyrocket” it was a low wing monoplane with a short fuselage that began aft of the wing’s leading edge with a twin tail assembly that featured a pronounced dihedral to the horizontal stabilizer. The main landing gear and tail wheel were fully retractable. The aircraft flew for the first time on 1 April 1940. Engine cooling problems arose in the initial flights, resulting in modification to the oil cooling ducts. Further modifications were made to the prototype including reduction in the height of the cockpit canopy, redesign of the engine nacelles, and extending the fuselage forward of the wing. Flight tests indicated good flying qualities for the XF5F-1. The counter-rotating props were a nice feature, virtually eliminating the torque effect on take-off the single-engine performance was good, rudder forces tended to be high in single engine configuration. Nevertheless, additional changes were needed after further flight tests that were not completed until 15 January 1942. In the meantime, Grumman began work on a more advanced twin-engine shipboard fighter, the XF7F-1 “Tigercat”, and further testing with the XF5F-1 supported the development of the newer design. The prototype continued to be used in various tests, although plagued by various landing gear problems, until it was struck from the list of active aircraft after it made a belly landing on 11 December 1944.
A land-based development of the Grumman XF5F-1 “Skyrocket” was the Grumman XP-50 “Skyrocket”. It entered into a USAAC contest for a twin-engine heavy interceptor aircraft. A prototype was ordered on November, but the aircraft lost the competition to the Lockheed XP-49 (Ref.: 24).