The Douglas TBD Devastator was the main US Navy torpedo bomber during the first six months of direct American involvement in the Second World War. Work on the Devastator began in 1934 in response to a Navy Bureau of Aeronautics specification calling for a torpedo bomber to replace the Martin BM-2 and Great Lakes TG-2 biplanes. The new aircraft would equip the new generation of American carriers being built in response to the increasing threat of war.
The prototype XTBD-1 was an all-metal low-wing monoplane. The three-man crew shared a single long cockpit under a greenhouse canopy – pilot at the front, then second pilot/ bombardier and torpedo aimer in the middle and finally the radioman/ gunner at the rear. The aircraft was designed to carry two .30 calibre M2 machine guns, one on a flexible ring mount in the rear cockpit and one fixed in the engine cowling. The torpedo was carried in a semi-recessed bay, sloping downwards towards the front of the aircraft. It could also carry bombs in place of the torpedo. It was the first American carrier based aircraft to be equipped with brakes on the main wheels.
The XTBD-1 first flew on 15 April 1935. Soon afterwards it was delivered to the Navy who subjected the new aircraft to an intensive series of tests. Carrier tests began in December 1935. The aircraft passed with flying colours. It had a top speed of close to 200 mph, a cruising speed of 100 mph when carrying a torpedo and a range of 435 miles. This compared very well to contemporary torpedo bombers such as the Fairey Swordfish, with a top speed of only 139 mph.
On 3 February 1936 the US Navy placed an order for 114 of the new aircraft. The main change between the XTBD-1 and the TBD-1 came in the cockpit. The low level canopy of the prototype was replaced one that peaked just behind the pilot. This allowed the aircraft to be given a roll-over pylon. The 800 hp engine of the prototype was replaced by a 900 hp Pratt & Whitney R-1830-64 model. When it entered service, the TBD-1 was the most advanced aircraft in American service.
One aircraft was modified to use floats, as the TBD-1A. This design never entered mass production, but the single aircraft was used in experiments to improve the performance of the Mk XIII torpedo and then as a general test bed for the TBD-1.
The TBD-1 entered service with VT-3, the Torpedo Squadron allocated to the USS Saratoga (CV-3), on 5 October 1937. Over the next couple of years the TBD gradually replaced the older torpedo bombers on every American carrier, and equipped the USS Hornet and USS Wasp as they entered service. The aircraft received the name Devastator on 1 October 1941, when the US Navy first gave its aircraft official names.
The US Navy’s Pacific carriers were famously away from harbour on 7 December 1941, when the Japanese launched their surprise attack on Pearl Harbor. Their Devastators were thus available to play a role in the earliest American counter attacks, a series of carrier raids on Japanese held islands, starting from February 1942. One thing became clear during these raids – the ultramodern aircraft of 1937 was beginning to show its age. Five years after its introduction it was too slow and did not have long enough range. Worse, the Mk XIII torpedo had not been reliable, tending to miss most of the time and to not explode when it hit. However, losses had been low, and the US Navy was encouraged by these early encounters.
The TBD played its part in the first major encounter between Japanese and American carrier forces, the battle of the Coral Sea. The battle began well for the aircraft. During an attack on the Japanese carrier Shoho, the TBDs scored seven direct hits for the loss of only two aircraft. The Japanese carrier soon sank. A second attack, launched against the Shokaku failed to score any hits on the Japanese carrier. However, losses were once again light.
The front line carrier of the Devastator came to an abrupt end as a result of losses suffered during the battle of Midway. On 4 June three squadrons of TBDs, containing 41 aircraft, made an attack on the Japanese carriers. VT-8 lost all fifteen aircraft launched, with only one pilot surviving. VT-6 lost 10 out of 14 aircraft launched; VT-3 lost 10 of 12. Of the 41 TBDs launched against the Japanese carriers, only 6 survived. No torpedo hits were scored.
The Devastators had been caught by Zero fighters, and slaughtered. The only redeeming feature of the attack was that the Devastators had pulled the Zeros out of place, allowing American dive bombers to launch a virtually unopposed attack on the Japanese fleet, sinking three fleet carriers – the Akagi, Soryu and Kaga.
Soon after Midway the TBD Devastator was withdrawn from front line service. Not only had it proved to be very vulnerable in battle, it was becoming very scarce. The original order of 114 aircraft had been boosted by a second order for 15 aircraft in August 1938, but nearly as many aircraft had been lost in peace time accidents. Training squadrons needed ten aircraft. The squadrons at sea before the battle of Midway thus contained just about every single TBD Devastator available to the US Navy. Almost half of them were lost at Midway. It had always been planned to phase out the TBD in favour of the Grumman TBF Avenger – Midway simply sped up those plans. Over the next two years the Devastator was used by a dwindling number of training establishments, until it was finally retired in 1944.
Engine: Pratt & Whitney R-1830-64 Radial engine
Span: 50 feet
Length: 35 feet
Max Speed: 206 mph
Ceiling: 19,700 feet
Range: 700 miles
Armament: One .30 calibre machine gun in rear cockpit and one .30 or .50 calibre machine gun in the engine cowling.
Bomb load: One Mk XIII Torpedo or 1,200lbs of bombs.