Douglas TBD Devastator

The Douglas TBD Devastator was a torpedo bomber of the United States Navy, ordered in 1934, it first flew in 1935 and entered 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of aircraft development caught up with it, and by the time of the Japanese attack on Pearl Harbor the TBD was already outdated.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 The type was immediately withdrawn from front line service, replaced by the Grumman TBF Avenger.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


Ordered on 30 June 1934, and entered into a US Navy competition for new bomber aircraft to operate from its aircraft carriers, the Douglas entry was one of the winners of the competition. Other aircraft ordered for production as a result of the competition included the Northrop BT-1 which would evolve into the SBD Dauntless, the Brewster SBA and the Vought SB2U Vindicator.

The XTBD Devastator, which flew for the first time on 15 April 1935, marked a large number of "firsts" for the US 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 10 in below the wings to permit a "wheels-up" landing which might limit any damage to the aircraft. 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 position, 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 1200 lb Bliss-Leavitt Mark 13 aerial torpedo or a 1000 lb bomb, to be carried semi-recessed into a bomb bay. Alternatively, three 500 lb general-purpose bombs: one under each wing root and one inside the bomb bay, or 12 100 lb fragmentation bombs: six under each wing root, 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 .30 in Browning machine gun for the rear gunner. Fitted in the starboard side of the cowling was either a .30 in or .50 in M2 Browning machine gun.

The powerplant was a Pratt & Whitney R-1830-64 Twin Wasp radial engine of 850 hp, an outgrowth of the prototype's Pratt & Whitney XR-1830-60/R-1830-1 of 800 hp. 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 (Naval Air Station) Anacostia and Norfolk bases. After successfully completing torpedo drop tests, the prototype was transferred to the USS Lexington 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 US Navy's Bureau of Aeronautics (BuAer), and starting from 1937, began to equip the carriers USS USS Saratoga (CV-3), USS Enterprise (CV-6), Lexington, USS Wasp (CV-7), USS Hornet (CV-8), USS Yorktown (CV-5) and USS Ranger (CV-4). 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 US 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 US entered World War II. By then, attrition had reduced their numbers to just over 100 aircraft. The US 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, with TBDs from Enterprise and Yorktown attacking targets in the Marshall and Gilbert Islands, Wake and Marcus Islands, while TBDs from Yorktown and Lexington struck Japanese shipping off New Guinea on 10 March. In the Battle of the Coral Sea Devastators helped sink the Japanese aircraft carrier JAPANESE AIRCRAFT CARRIER Shōhō on 7 May, but failed to hit another carrier, the JAPANESE AIRCRAFT CARRIER Shōkaku, the next day.

Faults 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 defects 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, the 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 spending time assembling a well-coordinated attack involving the different types of aircraft - fighters, bombers, torpedo planes - reasoning that attacking the Japanese would prevent a counterstrike against the US carriers. The TBDs from Hornet and Enterprise lost contact with their escort and started their attacks without fighter protection.

The Devastator proved to be a death trap for its crews: slow and hardly 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 Zeros. 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 take sharp evasive maneuvers. By obliging the Japanese to keep their flight decks clear and to continually cycle and reinforce their combat air patrols, they prevented any Japanese counter-attack against the American carriers, just as Spruance had anticipated. 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, which dive-bombed and fatally damaged three of the four Japanese carriers about one hour after the first TBD torpedo attacks had developed.

Obsolescence
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; the last TBD in the US 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.

In fairness to the Devastator, the newer TBF Avengers were similarly ineffective in 1942, losing five out of six aircraft without scoring a hit at Midway. The Avengers' only successes in 1942 would be against the light carrier JAPANESE AIRCRAFT CARRIER Ryūjō and the battleship JAPANESE BATTLESHIP Hiei In the initial part of the Pacific War, the poor performances of US torpedo bombers was due to the vulnerability of that type in general against the fire from AAA and defending fighters, plus the inexperience of American pilots and lack of coordinated fighter cover, as well as serious defects in US torpedoes which were not discovered and corrected until the fall of 1943. It took growing American air superiority, improved attack coordination, and more experienced pilots, before the Avengers were able to successfully accomplish their roles in subsequent battles against Japanese surface forces.

After the debacle at Midway, the surviving TBD Devastators in VT-4 and VT-7 (approximately three dozen survivors) 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 800 hp XR-1830-60, one built.


 * TBD-1
 * Production variant powered by a 850 hp R-1830-64, 129 built.


 * TBD-1A
 * One TBD-1 modified with twin floats.

Operators



 * 🇺🇸 United States
 * United States Navy
 * VT-2 used 58 Devastators between December 1937 and May 1942.
 * VT-3 used 71 Devastators between October 1937 and June 1942. They starred in the 1941 movie Dive Bomber.
 * VT-4 used nine Devastators between December 1941 and September 1942.
 * VT-5 used 57 Devastators between February 1938 and June 1942.
 * VT-6 used 62 Devastators between April 1938 and June 1942.
 * VT-7 used 5 Devastators between January 1942 and July 1942.
 * VT-8 used 23 Devastators between September 1941 and June 1942.
 * VB-4 used three Devastators between December 1941 and January 1942.
 * VS-42 used three Devastators between December 1940 and December 1941.
 * VS-71 used eight Devastators between December 1940 and June 1942.
 * VS-72 used two Devastators in June 1941.
 * VU-3 used a single Devastator from January until May 1940.
 * United States Marine Corps
 * VMS-2 used a single Devastator, BuNo. 1518, from 26 March 1941 till 5 June 1941, loaned from VT-3.

Survivors
There are no surviving aircraft in museums or private collections, nor are there any currently under restoration. However, below are four crashed aircraft that are known to exist and are the closest to a complete airframe in the world. It is not known if anyone is going to recover and restore these aircraft, as there has been no news on the recovery off San Diego since 2011.


 * TBD-1, BuNo.0298
 * Ex-VT-5 / USS Yorktown (CV-5) "5-T-7", Jaluit Lagoon, Marshall Islands.


 * TBD-1 BuNo.0353
 * Ex-NAS Miami, Atlantic Ocean, Miami, Florida.


 * TBD-1 BuNo.1515
 * Ex VT-5 / USS Yorktown (CV-5) "5-T-6", Jaluit Lagoon, Marshall Islands.


 * TBD-1 BuNo.0377
 * Ex-VT-2 / USS Lexington (CV-2) "6-T-7", Pacific Ocean, Mission Beach, California.

Notable appearance in media
Dive Bomber (1941) was an American 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 USS Enterprise (CV-6) as well as the NAS North Island in San Diego.