When, in the early 1930s, the Americans began modernizing their navy, they considered the replacement of old destroyers from the Great War as one of the most urgent tasks
However, the new projects, disappointed and dissatisfied the sailors. Some of these vessels were heavily overloaded (e.g. Sims class and early Benson ships), as a result some of the weaponry had to be removed. By proceeding with the design of subsequent series of destroyers, efforts were made to respect the Treaty restrictions (London, 1936). The originally formulated requirements envisaged a destroyer with a displacement of 1,600 tons and armament consisting of not less than 4.5-inch (127 mm) guns and 10 x 533mm torpedo tubes and a speed of 36 knots. There were six variants of vessels slightly different from earlier Benson and Sims classes. It soon became apparent that additional requirements could not be met within the limits of this displacement. This mainly concerned making space for a 28-mm quadruple automatic cannon and more powerful ASuW weapons
The constructors were spared the problems by the outbreak of war in Europe, removing all restrictions on the construction of new ships. The new project was initiated only one month after the outbreak of the global conflict. Messrs Gibbs and Cox from New York dealt with its development. The project of the destroyer Fletcher was approved as early as on 27 January 1940. The displacement of the new ship increased to 2,100 t. This additional displacement of 400 tons compared to its predecessor allowed the installation of 5.5-inch (127 mm) cannons, two 5-tube 533 mm torpedo assemblies, and a 4-barrel 1.1-inch (28 mm) AA gunn as well as 4 x 0.5-inch (12.7 mm) machine guns. Increased displacement was also used for the installation of anti-splinter armour for the broadsides and the deck above the engine rooms.
It is important that at the Fletcher’s, already design stage, a displacement reserve was planned for future upgrades, while in earlier types of destroyers more powerful armament was isntalled at the expense of deterioration of stability and sea worthiness.
After a 20-year break, the concept of a flush deck destroyer returned. This solution saved weight and increased structural strength, but unfortunately resulted in a reduction in the hull’s internal volume. Therefore, some of the rooms had to be moved to deck superstructures, which in this way grew to the size not often found on destroyers. The output of the of the engine increased to 60,000 HP to give the ship a maximum speed of 38 knots. The ships were mainly intended to provide AA defence for the battleships and according to the prevailing views a destroyer should have exceeded the speed of the vessels she escorted by at least 5 knots. Unfortunately, with displacement close to full, the 34 knots barrier was rarely overcome.
At the turn of 1941/1942 not a very effective 1.1-inch (28 mm) gun called „Chicago Piano” was replaced with one double 40-mm Bofors mount, and the projected 0.5-inch (12.7 mm) machine guns with single-mount 20 mm Oerlikon cannons. However, both Fletcher and several early ships of this class entered service with the 1.1 inchers. All these ships were delivered without radars: SC aerial observation and SG surface observation.
The core of the Fletcher gun armament consisted of five 5-inch (127 mm) multi-purpose guns with a barrel length of 38 calibres in tower-like closed single mounts. The gun itself, thanks to numerous advantages, has gained the opinion of one of the best used in the wartime. The semi-automatic lock allowed to achieve a high rate of fire. On average, an average trained crew achieved 12-15 shots/min, but the best even achieved 22 shots/min. Fletcher also received a modern Mk. 37 fire control system with the Mk. 4 multi-purpose radar. For the first time, instead of on the bridge, the fire control compartment was located in a special room in the hull below the waterline. To fight against submarines, the ship was equipped with two aft tracks with a supply of 28 depth charges and six depth-charge launchers, the so-called K-guns, three on each side of the stern deck.
The ship had a typical two-shaft propulsion system. It consisted of: two sets of steam turbines with a double reduction gear, one set per shaft with 30,000 HP (22,682 kW) and 2 water-tube boilers with natural circulation generating 50 t steam/h and working pressure 42 Bars and temperature 250° C. The boilers were arranged in an unusual way - across the hull. The shafts rotated by 3-blade propellers with a diameter of 3.50 m. The ship was equipped with a single rudder blade.
The Fletcher family
Initially, it was planned to build a series of 188 ships, but eventually 175 were built. After the programme was accepted, the very first 24 destroyers were ordered. The contract for the basic group of destroyers, numbering over 100 vessels, was concluded on 19 July 1940. Another 56 ships were ordered when the US entered the war. Nine American shipyards received orders for the construction of the series. Most of the destroyers were commissioned between 1942 and early 1944, but some were completed at the turn of 1944/45. The average construction time for one destroyer did not exceed 6 months. With such a large series built in many shipyards, it is understandable that the design parametres of the ships differed in individual lots. There were differences in dimensions (just several inches) and displacement. The Fletchers were divided into two groups, although the differences between them were not significant. Group One had Mk. 37 rangefinders placed on a round mount, while on the vessels of Group Two, the Mk.37 were installed directly on the top of the wheelhouse. The difference in the shape of the wheelhouse was more noticeable - the eraly destroyers (56 ships) had a rounded „high” wheelhouse, while the others had an angular, quadrangular „lower” wheelhouse. The latter was more spacious, provided better visibility and was simpler to build. The Royal Navy’s war experience prompted Americans to redesign the combat bridge. Until now, American destroyers had closed bridges, unlike the British open ones, which provided better observation and more effective defence against air attack. The first open bridge was applied on the DD 518 Brownson (commissioned on 24 September 1942).
Six ships (DD 476 – DD 481) were planned to be equipped with a catapult for reconnaissance floatplane. They were to be mounted on the superstructure behind the second funnel in place of the dismantled aft torpedo tube assembly and No. 3 127 mm gun. The AA armament at the same time was reduced to one twin 40 mm Bofors mount and 8 single 20 mm Oerlikons. However, only three ships were built this way: DD-476 Pringle, DD-477 Stevens and DD-480 Helford. The three remaining vessels were completed in the standard version. Aviation equipment proved to be inefficient and was dismantled in the second half of 1944.
It is also worth mentioning two other ships of this class built as experimental vessels for testing new propulsion solutions. DD 482 Watson was planned to be equipped with a 24 diesel engines, while DD-452 Percival was to receive special high-pressure steam boilers. With the outbreak of war, their construction was suspended and in 1946 the order was cancelled.
During the war, the Fletchers were constantly modified to adapt their capabilities to the growing threat from the air. They dealt exclusively with the development of the AA weapons and ships’ electronics. The first changes occurred in the late 1941 when the 28-mm automatic machine was replaced with a double 40-mm Bofors and six 20-mm Oerlikons. The increase in weight was compensated by removing parts of the armour and lowering the base of the Mk. 37 rangefinder. In June 1943, the AA weaponry already included five twin Bofors guns. Such a set was installed on the ships freshly commissioned, while on ships already operational additional equipment was installed during repairs. By the end of 1944, 157 of the 160 Fletchers in sevice had five twin 40 mm Bofors’ and seven 20 mm Oerlikons. In 1945, after the massacre of the American destroyers near Okinawa made by the kamikaze pilots, the armament was further strengthened.
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