Douglas TBD Devastator


It seems to me that the reputation of the Douglas TBD Devastator has been somewhat blackened by circumstance. It was a very early monoplane design with ludicrously inadequate power. While its performance was still better than that of the Swordfish, it faced much tougher defenses. Moreover, USN doctrine for its employment was inadequate, in that it did not sufficiently stress delivery of a massed, coordinated attack by dive bombers and torpedo bombers. Finally, it was lumbered with a torpedo which, while fundamentally adequate, was not very effective in 1942 due to several problems.

Parshall and Tully say that Japanese CAP discipline was poor at Midway, and that the IJN system was faulty. The CAP fighters did not have radios. The ships communicated with them by firing main-battery guns in the direction of any USN planes they saw. The CAP fighters then flew off that way to intercept. In more than one instance, they kept chasing attackers after they were no longer a threat–rather than return to the carriers and return to their original formation, which stacked them at various altitudes. These were the factors, the authors say, that made it possible for the dive bombers to get through. Kido Butai, lacking radar, did not see them. The CAP pilots chased retreating TBDs instead of reforming over the carriers. The torpedo attack did play a role, but it was not as simple as the traditional American histories describe it.

The Japanese Navy was disappointed with the B2M design so it turned to its own resources in designing a replacement. The First Naval Air Technical Arsenal’s engineers, led by Suzuki Tamefumi, designed the three-seater biplane Type 92 Carrier Attack Bomber (also known as the B3Y1) that entered service in 1933. Wing structure was of wood and the fuselage structure of welded steel tube. Powered by a 750-horespower Type 91 water-cooled engine, the B3Y1 had a top speed of 136 miles per hour and a range of 500 miles. This model’s engine also proved unreliable and the performance, especially in range, was unsatisfactory, so a new design was prepared by Kawasaki Sanae at the First Naval Air Technical Arsenal that entered service in early 1937 as the Type 96 Carrier Attack Bomber (or B4Y1). The new design married the wings of the successful E7K1 shipboard floatplane to a new fuselage and tail unit to produce a three-seater biplane with all-metal structure. Powered by an 840-horsepower Nakajima Hikari radial engine, it had a maximum speed of 173 miles per hour and a range of 978 miles, both markedly superior to any of its precursors or any similar machine in service, although this superiority was cut short by the introduction of Douglas’s monoplane TBD-1 later in 1937.

Torpedo-bomber development for carrier deployment in the United States Navy generally followed a similar pattern as in other fleets, although a small number of very large Douglas T2D twin-engine aircraft briefly operated from the Langley in 1927 before they were fitted with floats and redesignated patrol types to avoid political conflict with the Army Air Corps. American carriers used essentially a single design from 1925 until 1937. The initial version, the Martin T3M-2, was a three-seater biplane powered by a 770-horsepower Packard 3A-2500 water-cooled engine that gave it a maximum speed of 109 miles per hour and a range of 630 miles. Subsequent versions, introduced from 1928, used radial engines, either the 525-horsepower Pratt & Whitney Hornet or the 620-horsepower Wright Cyclone, which gave the final version, the Great Lakes TG- 2, a maximum performance of 127 miles per hour and a range of 330 miles. The Douglas TBD-1 re-equipped the fleet’s torpedo squadrons in 1937 and 1938, marking a great advance in capabilities. This all-metal low-wing monoplane of stressed-skin construction also introduced flaps to aid slow-speed handling, a retractable undercarriage, and power-operated wing folding. Powered by a 900- horsepower Pratt & Whitney Twin Wasp radial engine driving a variable- pitch propeller, the TBD-1 had a maximum speed of 206 miles per hour and a range of 716 miles, both vastly superior to the performance of its precursors.