The heaviest single-engined aircraft of World War 2, Grumman’s eponymous Avenger became one of the most potent torpedo bombers of World War 2. Its design was characterised by its portly fuselage, three-man crew and multi-role capabilities, and it soon began to epitomise the changing tide of war in the Pacific as the US took the battle towards Japan. The success of the Avenger stemmed beyond its use by the US Navy for the aircraft saw extensive service with British and Commonwealth forces as well as becoming a staple of aircraft inventories around the world in the Cold War years.
In 1939, the US Navy’s Bureau of Aeronautics issued a request for proposals for a new torpedo/level bomber to replace the outdated Douglas TBD Devastator. For the new aircraft, BuAer specified a crew of three (pilot, bombardier, and radio operator), each armed with a defensive weapon, as well as a dramatic increase in speed over the TBD and an ability to carry a Mark 13 torpedo or 2,000lb of bombs. The US Navy selected a Grumman design as the winner of the competition and placed an order for 286 aircraft on 8 April 1940 – this before its XTBF-1 prototype had even flown. Development proved to be unusually smooth, the only aspect that proved challenging was meeting a BuAer requirement that called for the rear-facing defensive gun to be mounted in a power turret. Powered by a single Wright R-2600-8 14-cylinder Cyclone radial piston engine, the XTBF-1 made its maiden flight on 1 August 1941 and although it was soon lost in a crash, rapid production continued. During the opening ceremony of Grumman’s new production facility intended to manufacture the new XTBF-1, word came down that the Japanese had attacked Pearl Harbor. It has often been stated that this is when the TBF became known as the ‘Avenger’, but in truth it had been so named months earlier.
Design of the Grumman TBF Avenger was conventional and followed the lessons learned with previous Grumman aircraft attempts including the wide-area wings. There were three crew members: pilot, turret gunner and radioman/bombardier/ventral gunner. One .30in calibre machine gun was mounted in the nose, a .50in (12.7mm) gun was mounted right next to the turret gunner’s head in a rear-facing electrically powered turret, and a single .30in hand-fired machine gun mounted ventrally (under the tail), which was used to defend against enemy fighters attacking from below and to the rear. The wings were power- folding and could set flat up against the sides of the fuselage for improved stowage aboard the space-strapped carriers of the day. The undercarriage consisted of two main landing gear legs (retracting under each wing away from the fuselage centreline) and a retractable tail wheel. The undercarriage was reinforced enough that they could double as airbrakes in the dive-bombing role. The Avenger had a large bomb bay, allowing for one Mark 13 torpedo, a single 2,000lb (907kg) bomb, or up to four 500lb (227kg) bombs. Avengers were primarily completed with the Wright R-2600 Cyclone 14-cylinder radial piston engine series outputting 1,700 to 1,900hp with many forms including a supercharger. Top speed was in the vicinity of 275mph with an operational range out to 1,000 miles. The aircraft could hit service ceilings of 30,000ft with a 2,000ft per minute rate-of-climb. The aircraft had overall ruggedness and stability, and pilots say it flew like a truck, which ideally suited its role.
After hundreds of the original TBF-1 models were built, the TBF-1C began production, but by 1943 Grumman began to slowly phase out production of the Avenger to produce F6F Hellcat fighters, and the Eastern Aircraft Division of General Motors took over production, with these aircraft being designated TBM. Starting in mid-1944, the TBM-3 began production (with a more powerful powerplant and wing hardpoints for drop tanks and rockets). The dash 3 was the most numerous of the Avengers (with about 4,600 produced). However, most of the Avengers in service were dash-1s until near the end of the war in 1945.
Initial combat actions for the TBF Avenger were recorded during the famous Battle of Midway on 4 June 1942, but it proved to be a baptism of fire. Of the six aircraft launched into battle with VT-8, only one returned home and this with a wounded bombardier and dead tail gunner. Later in the war, with growing US air superiority, better attack co-ordination and more experienced pilots, Avengers were able to play vital roles in the subsequent battles against Japanese surface forces.
On 24 August 1942, the next major naval battle occurred at the Eastern Solomons. Based on the carriers Saratoga and Enterprise, the 24 TBFs present were able to sink the Japanese light carrier Ryujo and claim one dive bomber, at the cost of seven aircraft. The first major success for the TBFs was at the battle of Guadalcanal in November 1942, when Marine Corps and Navy Avengers helped sink the battleship Hiei, which had already been crippled the night before.
The Royal Navy’s Fleet Air Arm also used the Avenger, initially calling the type the TBF Tarpon befoe reverting back to its original name. Beginning in 1943, British squadrons began seeing service in the Pacific as well as conducting anti-submarine warfare missions over home waters. The aircraft was also provided to the Royal New Zealand Air Force, which equipped four squadrons with the type during the conflict.
Nicknamed the ‘Turkey’ by its aircrews because of its size, the Avenger remained the US Navy’s primary torpedo bomber for the remainder of the war. While seeing action at key engagements such as the Battles of the Philippine Sea and Leyte Gulf, the Avenger also proved an effective submarine killer. During the course of the war, Avenger squadrons sank around 30 enemy submarines in the Atlantic and Pacific. As the Japanese fleet was reduced later in the war, the TBF/TBM’s primary role began to diminish and the Avenger was evolved into a myriad of other useful roles including that of dedicated reconnaissance platform, target towing, airborne early warning (AEW), anti-submarine warfare (ASW) and light carrier-based transport. Overall, total production of the TBF Avenger series ranged between 9,836 and 9,839 aircraft (sources vary on the exact count).
Grumman TBF/TBM Avenger
Crew: Three: pilot; radioman/bombardier/ventral gunner; and turret gunner
Length: 40ft 11.5in (12.48m)
Wingspan: 54ft 2in (16.51m)
Height: 15ft 5in (4.7m)
Empty weight: 10,545lb (4,783kg)
Loaded weight: 17,893lb (8,115kg)
Powerplant: Wright R-2600-20 radial engine of 1,900hp
Top speed: 275mph
Service ceiling: 30,100ft (9,170m)
Armament: 1× 0.30in (7.62mm) #nose-mounted M1919 Browning machine gun (on early models) or 2× 0.50in (12.7mm) wing- mounted M2 Browning machine guns; 1× 0.50in (12.7mm) dorsal-mounted M2 Browning machine gun; 1× 0.30 in (7.62mm) ventral-mounted M1919 Browning machine gun
Ordnance: Up to 2,000lb (907kg) of bombs or 1× 2,000lb (907kg) Mark 13 torpedo
Rockets: 8× 3.5in forward firing aircraft rockets or high velocity aerial rockets