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Destroyers (DD)


Photograph of Fletcher-class destroyer

National Archive # 19-N-31243

The destroyer of World War II was a fast unarmored warship of 1000 to 3000 tons displacement. It was typically armed with four- to five-inch (10 to 13 cm) guns, torpedoes, antisubmarine weapons, and light antiaircraft weapons for point defense.

Destroyers were originally developed to protect capital ships from torpedo boats. This required rapid-firing weapons and enough speed, range, and sea keeping ability to accompany and screen the larger ships. With the advent of the submarine, the destroyer became the principal antisubmarine screening ship, and depth charges and sound gear were added to its inventory. During the First World War, the sound gear took the form of sensitive hydrophones, which could detect noises from a nearby submerged submarine. Most of the major powers had independently developed sonar, which uses an active signal to more precisely locate submarines, by the start of the Second World War.

The antisubmarine mission continued through World War II, but destroyers proved to be the workhorses of the fleet. Their main gun armament shifted to dual-purpose weapons useful against aircraft (of which the best was the U.S. 5”/38 gun) and Allied destroyers acquired sophisticated radars. This gave them a significant antiaircraft escort capability. Because of their shallow draft, destroyers were useful for shore bombardment, because they could get in close to shore for accurate gunnery.

The proper role of destroyers was debated vigorously between the world wars. In the U.S. Navy, the younger officers commanding the destroyers favored smaller, faster ships with heavy torpedo armament suitable for an offensive role, while the older officers favored ships that sacrificed some speed for good sea keeping and endurance, making them more suitable for screening the battle line. Destroyers were also needed to act as scouts for the battle fleet, since Congress had provided almost no funding for the light cruisers that usually filled the scouting role in other navies. The British were even more aware of the conflicting requirements for their destroyer forces, since their destroyers were seen both as offensive torpedo craft to wreck an enemy battle line, as screening vessels to protect their  own battle line, and as escort vessels for Britain's vast overseas trade.

American destroyers built before the war were almost universally top heavy and very uncomfortable for their crews. Friedman (2004) attributes this to poor coordination between the Bureau of Construction and Repair and the Bureau of Engineering, which shared responsibility for ship design. The two were merged in 1940 into the Bureau of Ships, which seems to have resolved the problem: The Fletchers, built during the war, were stable and very capable ships. Japanese destroyers were also very capable and did not suffer from stability problems, largely because the Japanese had learned this lesson from the Tomozuru Incident, in which a torpedo boat capsized in a typhoon in the 1930s. (Two pre-war American destroyers would capsize in a typhoon late in the war.) American destroyers had powerful antiaircraft armament but miserable torpedoes, while Japanese destroyers were almost the opposite, with poor antiaircraft and the best torpedo in the world — the Long Lance. British destroyers started the war with even worse antiaircraft defenses than the Japanese, but better torpedoes than the Americans, and they excelled at antisubmarine warfare.

Much of the difference between American and Japanese destroyers was a reflection of different naval doctrine. Whereas the Americans had settled on balanced designs, suitable for defensive screening roles as well as torpedo attacks against the enemy, the Japanese clung to torpedo attack as the primary mission of the destroyer for much longer. Their role in Decisive Battle Doctrine was to throw the American battle line into as much confusion as possible prior to the decisive gun duel with the Japanese battle line.

American destroyers were designed to have a cruising radius of 5,500 nautical miles (10,200 km) with operations in the Pacific in mind. However, when steaming at their maximum speed of better than 30 knots, destroyers consumed fuel prodigiously. American practice was to maintain an equally lavish fleet train with enough tanker support to keep the destroyers going. The Japanese, with fewer tankers, often refueled their destroyers from the larger warships in the task force, a practice occasionally used by the Americans as well.

The British, faced with both tight naval budgets and the constraints imposed by the naval disarmament treaties between the wars, settled on a strategy of constructing both powerful destroyers to operate with the fleet and less expensive ships that could be mass produced in the great numbers needed for commerce protection. The latter were often rated as corvettes, sloops, or frigates rather than destroyers. The treaty limits on cruiser construction led to greater reliance on powerful destroyers to replace cruisers as protection from enemy surface raiders. Anticipating that their fleets might have to sail great distances to the theater of operations (the British already had Japan in mind), the screening role of destroyers received greater emphasis, and by 1932 all new British destroyers were being equipped with ASDIC (sonar). British destroyers were also designed so that they could be equipped at short notice with Two-Speed Destroyer Sweep (TSDS), a form of minesweeping gear usable at high speed by destroyers escorting a task force. However, the British were slow to adopt a main destroyer battery with significant antiaircraft capability, persuading themselves first that this was incompatible with good antisurface capability and then that a maximum gun elevation of less than 40 degrees was adequate for guns meant to fire at approaching aircraft that were still some distance away. However, by the time war broke out in the Pacific, the British were constructing destroyers with meaningful antiaircraft capability.

The Japanese began the war with 110 destroyers while the Americans had 68 destroyers in the Pacific, the British had just 8 in the Far East, the Dutch had 7, and the Australians had 2. However, while the Japanese constructed an additional 33 destroyers during the war, the Americans alone deployed an additional 302 destroyers to the Pacific before the surrender. Japanese destroyer losses were relatively heavy during the Solomons campaign, and Allied intelligence was quick to appreciate that the Japanese were suffering from a serious destroyer shortage in early 1943. This prompted Nimitz to issue an order on 13 April that destroyers be given higher target priority by submarines (second only to capital ships) in order to aggravate the Japanese destroyer shortage.

Destroyer Missions. American destroyers found themselves employed in four main roles during the war. As anticipated in prewar planning, they screened task forces, but primarily in an antiaircraft role rather than against light surface forces. They played a major role in shore bombardment, a mission also anticipated in prewar planning, but not nearly to the extent that actually took place. Antisubmarine operations were also far more important than anticipated. Finally, destroyers were a major part of what we would now call surface action groups in the Solomons and elsewhere, employing their torpedoes, not against the enemy battle line, but against enemy light surface forces. This mission was almost completely unanticipated.

One aspect of antiaircraft screening that became increasingly prominent under the kamikaze threat was radar picket duty. Fighter director teams had begun working from destroyers as early as late 1943. During the battle of Okinawa, destroyers were stationed 75 miles (120 km) from the fleet and close enough to each other to allow fighter directors to "hand off" control of fighters to neighboring destroyers as needed. However, the destroyers were not close enough for mutual support against either air or surface attack, and, as casualties mounted, picket destroyers began to be paired and to be supported by landing craft armed with antiaircraft weapons. Eventually each picket group was assigned a section of 12 fighters for local combat air patrol. Even this could not always prevent casualties, and consideration was given to converting submarines to radar pickets that could submerge after reporting incoming strikes. A better idea was Cadillac, a sophisticated (for its day) airborne early warning radar, which was not deployed in time to see combat operations, but was part of the plan for an invasion of Kyushu.

American destroyers were somewhat weak on antisubmarine armament prior to the war. The standard QC sonar could not be produced in sufficient quantity to equip the destroyers with two sets, as originally planned, and most had a single QC set throughout the war. The standard antisubmarine armament in 1941 was just two depth charge tracks with five Mark 7 depth charges each. As war approached and the need for a stronger antisubmarine armament became clearer, many of the older destroyers gave up a bank of torpedo tubes or a 5" gun mount (or both) in order to ship up to eight depth charge throwers and many more depth charges. Atlantic destroyers had priority, and few of the prewar Pacific destroyers shipped more than four depth charge throwers.

By the time the Pacific War was underway, most U.S. Navy officers had concluded from British experience in the Mediterranean that "... as carriers of torpedoes, destroyers now were secondary to submarines and torpedo planes" (Friedman 2004). As a result, dual-purpose gun armament was given higher priority than torpedo armament on the Allen M. Sumners and subsequent classes. By the time units of these classes were deployed, the Japanese Navy had been so whittled down that aircraft and submarines were indeed the major threat; but, in the meanwhile, there had been numerous torpedo actions in the Solomons and elsewhere. This played a role in the decision to continue arming destroyers with torpedoes in the postwar era.

The rule of thumb at the start of the Pacific War was that destroyers should have a top speed about 70 percent greater than the battle line. By the time the war ended, the fast battleships and carriers making up the core of the fleet were capable of better than 30 knots, and destroyers were barely keeping a 5-knot speed advantage. Cruising range was also a serious concern. One solution was nuclear propulsion, but it was the helicopter that would restore tactical mobility to the screen of surface groups.

Japanese destroyer classes

Akatsuki class

Akizuki class

Asashio class

Fubuki class

Hatsuharu class

Kagero class

Kamikaze class

Minekaze class

Momi class

Mutsuki class

Shimakaze

Shiratsuyu class

Wakatake class

Yugumo class

U.S. destroyer classes

Allen M. Sumner class

Bagley class

Benham class

Benson class

Caldwell class

Clemson class

Farragut class

Fletcher class

Gearing class

Gridley class

Mahan class

Porter class

Sampson class

Sims class

Somers class

Wickes class

British destroyer classes

"A" class

"Battle" class

"D" class

"E" class

"F" class

"G" class

"H" class

"J" class

"P" class

"Q" class

Saber class

"S" class

"Tribal" class

"U" class

Dutch destroyer classes

Tjerk Hiddes class

Van Galen class

Van Ghent class

Australian destroyer classes

Napier class

Stuart

"Tribal" class

Vampire class

French destroyer classes

2610 Tonnes class

Russian destroyer classes

Artem class

Leningrad class


References

Friedman (2004, 2006)

Morison (1953)

Roscoe (1953)
Wildenberg (1996)
Worth (2001)



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