The Douglas TBD Devastator was a torpedo bomber of the United States Navy, ordered in 1934, first flying in 1935 and entering service in 1937. At that point, it was the most advanced aircraft flying for the USN and possibly for any navy in the world. However, the fast pace of aircraft development caught up with it, and by the time of the Japanese attack on Pearl Harbor the TBD was already outdated. It performed well in some early battles, but in the Battle of Midway the Devastators launched against the Japanese fleet were almost totally wiped out. The type was immediately withdrawn from front line service, replaced by the Grumman TBF Avenger.

Design and development

The XTBD Devastator, which flew for the first time on 15 April 1935, marked a large number of "firsts" for the U.S. Navy. It was the first widely-used carrier-based monoplane as well as the first all-metal naval aircraft, the first with a totally-enclosed cockpit, the first with power-actuated (hydraulically) folding wings; it is fair to say that the TBD was revolutionary. A semi-retractable undercarriage was fitted, with the wheels designed to protrude below the wings to permit a "wheels-up " landing with only minimal damage. A crew of three was normally carried beneath a large "greenhouse" canopy almost half the length of the aircraft. The pilot sat up front; a rear gunner/radio operator took the rearmost seat, while the bombardier occupied the middle seat. During a bombing run, the bombardier lay prone, sliding into position under the pilot to sight through a window in the bottom of the fuselage, using the Norden Bombsight.

The normal TBD offensive armament consisted of either a Bliss-Leavitt Mark 13 aerial torpedo or a bomb. Alternately, three general-purpose bombs: one under each wing and one under the fuselage, or 12 fragmentation bombs: six under each wing, could be carried. This weapons load was often used when attacking Japanese targets on the Gilbert and Marshall Islands in 1942.Defensive armament consisted of a abbr=on}} machine gun for the rear gunner. Fitted in the starboard side of the cowling was either a or abbr=on}} machine gun.

The powerplant was a Pratt & Whitney R-1830-64 Twin Wasp radial engine, an outgrowth of the prototype's Pratt & Whitney XR-1830-60/R-1830-1. Other changes from the 1935 prototype included a revised engine cowling and raising the cockpit canopy to improve visibility.

The XTBD had a flat canopy that was replaced on production models by a higher, domed canopy over a roll over bar. Other than requests by test pilots to improve pilot visibility, the prototype easily passed its acceptance trials that took place from 24 April-24 November 1935 at NAS Anacostia and Norfolk bases. After successfully completing torpedo drop tests, the prototype was transferred for carrier certification. The extended service trials continued until 1937 with the first two production aircraft retained by the company exclusively for testing.

A total of 129 of the type were purchased by the U.S. Navy's Bureau of Aeronautics (BuAer), and starting from 1937, began to equip the carrieers. In pre-war use, TBD units were engaged in training and other operational activities and were gradually approaching the end of their useful service life with at least one aircraft being converted to target tug duty. By 1940, the U.S. Navy was aware that the TBD had become outclassed by the fighters and bombers of other nations and a replacement was in the works, but it was not yet in service when the U.S. entered World War II. By then, attrition had reduced their numbers to just over 100 aircraft. The U.S. Navy assigned popular names to its aircraft in late 1941, and the TBD became the Devastator, although its nickname "torpecker" was commonly used.

Operational history

In the early days of the Pacific war, the TBD acquitted itself well during February and March 1942 and in the Battle of the Coral Sea, in which Devastators helped sink the Shoho.

Problems were discovered with the Mark 13 torpedo at this point. Many were seen to hit the target yet fail to explode; there was also a tendency to run deeper than the set depth. It took over a year for the problems to be corrected. These problems were not fixed by the time of the Battle of Midway on 4 June 1942.

At Midway, a total of 41 Devastators, a majority of the type still operational, were launched from ''Hornet'', ''Enterprise'' and ''Yorktown'' to attack the Japanese fleet. The sorties were not well coordinated, in part because Rear Admiral Raymond A. Spruance ordered a strike on the enemy carriers immediately after they were discovered, rather than spend the time to assemble a well-ordered attack among the different types of aircraft: fighters, bombers, torpedo planes, reasoning that attacking the Japanese would prevent a counterstrike against the US carriers. The TBDs lost contact with their fighter escort and started their attacks without fighter protection.

The Devastator proved to be a death trap for its crews: slow and scarcely maneuverable, with light defensive weaponry and poor armor relative to the weapons of the time; its speed on a glide-bombing approach was a mere 200 mph, making it easy prey for fighters and defensive guns alike. The aerial torpedo could not even be released at speeds above 115 mph.Torpedo delivery requires a long, straight-line attack run, making the aircraft vulnerable, and the slow speed of the aircraft made them easy targets for the Mitsubishi A6M Zero s. Only four TBDs made it back to ''Enterprise'', none to ''Hornet'' and two to ''Yorktown'', without scoring a torpedo hit.

Nonetheless, their sacrifice was not completely in vain, as several TBDs managed to get within a few ship-lengths range of their targets before dropping their torpedoes, being close enough to be able to strafe the enemy ships and force the Japanese carriers to make sharp evasive maneuvers. As the carriers were in the midst of refueling and rearming operations with planes on the deck ready to take off, they were unable to launch these armed and fueled planes due to the TBD attacks, so this left the carriers in an even more vulnerable position. Furthermore, the heroic actions of the Devastator aircrews that day drew the Japanese air cover out of position. This window of opportunity was exploited by the late-arriving Douglas SBD Dauntless dive bombers led by Lieutenant Commander C. Wade McClusky and Max Leslie, and three of the four Japanese carriers were fatally damaged shortly afterwards.

The Navy immediately withdrew the TBD from front-line units after Midway; in any case, there were only 39 aircraft left. They remained in service briefly in the Atlantic and in training squadrons until 1944. The original prototype finished its career at NAS Norman, Oklahoma, and the last TBD in the U.S. Navy was used by the Commander of Fleet Air Activities-West Coast. When his TBD was scrapped in November 1944, there were no more. None survived the war and there are none known to exist on dry land today.

After the debacle at Midway, the surviving TBD Devastators in VT-4 and VT-7 remained in service for a short time before being shipped back to the United States where the aircraft were relegated to training duties for pilots and mechanics or were destroyed following use as instructional airframes for fire-fighting training. By late 1944, no TBD Devastators were left in the US Navy inventory.

Variants

XTBD-1

Prototype powered by a XR-1830-60, one built.

TBD-1

Production variant powered by a R-1830-64, 129 built.

TBD-1A

One TBD-1 modified with twin floats.

Survivors

There are no Devastators in any collection or museum. Several wrecks are known and are being investigated for possible salvage and restoration:

Notable appearance in media

''Dive Bomber'' (1941) was a American propaganda film directed by Michael Curtiz. It is notable for both its Technicolor photography of pre-World War II United States Navy aircraft featuring the TBD Devastator, and scenes on the aircraft carrier as well as the NAS North Island in San Diego.