USS Balch — the eighth and final Porter-class destroyer — on 23 September 1936
Class overview
Name	Porter class
Builders	New York Shipbuilding, NJ (4) Bethlehem Fore River, MA (4)
Operators	United States Navy
Preceded by	Farragut class
Succeeded by	Mahan class
Built	1933–1937
In commission	1936–1950
Completed	8
Lost	1
Retired	7
General characteristics
Type	Destroyer
Displacement	1,850 tons standard, 2,663 tons full load
Length	381 ft (116 m)
Beam	36 ft 2 in (11.02 m)
Draft	10 ft 5 in (3.18 m)
Installed power	4 Babcock & Wilcox boilers, 2 geared steam turbines, 50,000 shaft horsepower (37,000 kW)
Propulsion	2 shafts
Speed	37 kn (69 km/h; 43 mph)
Range	6,380 nautical miles (11,820 km; 7,340 mi) at 12 kn (22 km/h; 14 mph)
Complement	13 officers, 193 enlisted (peacetime) 290 (wartime)
Sensors and processing systems	as built: 2 × Mk35 GFCS[1] typical: single Mk35 or Mk37 GFCS. 1 × SC radar
Armament	As Built: 8 × 5-inch/38 caliber guns (127 mm) (4 × 2) 8 × 1.1-inch/75 caliber guns (28 mm) (2 × 4) 2 × .50 caliber machine guns (12.7 mm) 8 × 21-inch (533 mm) torpedo tubes (2 × 4), 16 torpedoes 2 × Depth charge stern racks c. 1942: 8 × 5-inch/38 caliber guns (4 × 2) 2 × Bofors 40 mm guns (1 × 2) 6 × 20 mm Oerlikon cannons 8 × 21 inch torpedo tubes (2 × 4), 16 torpedoes 2 × Depth charge stern racks
Notes	Armament varied greatly from ship to ship during World War II.

The Porter-class destroyers were a class of eight 1,850-ton large destroyers in the United States Navy. Like the preceding Farragut-class, their construction was authorized by Congress on 26 April 1916, but funding was delayed considerably. They were designed based on a 1,850-ton standard displacement limit imposed by the London Naval Treaty; the treaty's tonnage limit allowed 13 ships of this size, and the similar Somers class was built later to meet the limit. The first four Porters were laid down in 1933 by New York Shipbuilding in Camden, New Jersey, and the next four in 1934 at Bethlehem Steel Corporation in Quincy, Massachusetts. All were commissioned in 1936 except Winslow, which was commissioned in 1937. They were built in response to the large Fubuki-class destroyers that the Imperial Japanese Navy was building at the time and were initially designated as flotilla leaders. They served extensively in World War II, in the Pacific War, the Atlantic, and in the Americas. Porter was the class' only loss, in the Battle of the Santa Cruz Islands on 26 October 1942.

The larger destroyer leader type had been under active consideration since 1921. Indeed, the General Board recommended the construction of five of the type in that year. One factor in favor of leaders was the Navy's total lack of modern light cruisers, only partly alleviated by the ten Omaha-class ships built in the 1920s. Naval historian Norman Friedman believed that the great number of Wickes and Clemson-class destroyers hindered the U.S. Congress from purchasing new leaders. The General Board was very interested in equipping such a type with the new higher pressure and higher temperature steam propulsion equipment also proposed for the Farragut-class destroyers; this would extend the ships' range.^[2] The London Naval Treaty and large French destroyers (France did not sign the treaty and built ships well in excess of its limits) seem to have become the tipping points, with the 1930 recommendations beginning the cycle to actually build ships.^[3] The Geneva proposals for destroyers also seem to have influence the design, as the Destroyer Leader proposals limited themselves to 1,850 tons per the proposals; these tonnage limits were eventually included in the London treaty.^[3]

The Porters had the same propulsion technology as the immediately preceding Farraguts, with 400 psi (2,800 kPa) steam superheated to 645 °F (341 °C). The plant was somewhat larger than in the Farraguts, with designed horsepower increased from 42,800 shaft horsepower (31,900 kW) to 50,000 shaft horsepower (37,000 kW), resulting in a speed of 37 kn (69 km/h; 43 mph).^[4] Along with the improved fuel efficiency resulting from superheated steam, the four boilers included economizers to further extend the ships' range by preheating incoming feedwater. The main steam turbines were manufactured by New York Shipbuilding in the case of the ships built by that yard. However, as in the Farraguts, the main turbines had single-reduction gearing and no cruising turbines, limiting their efficiency.^[5]

There were extensive discussions about the armament, the 5-inch (127 mm)/25-caliber anti-aircraft (AA) gun being favored as being easy to work and train in a fast-moving and lively type of ship. The other candidate was the 5-inch/51-caliber surface type, being very powerful but all but useless against aircraft. It was a discussion made more interesting as the 5-inch/38-caliber dual-purpose gun became available in the early 1930s and the Ordnance Department favored it rather strongly. The 5-inch/38-caliber gun was simply a 5-inch/25-caliber gun with the same projectiles and a longer barrel, but significantly increased range against both air and surface targets.^[6][3] The class was originally built with eight Mk 12 guns in four Mark 22 single-purpose (surface action only) twin enclosed mounts; the single-purpose mounts were adopted to save weight.^[6] Anti-aircraft protection was provided by two quadruple 1.1-inch (28 mm) mounts; in the 1930s this was considered sufficient. Although the Porters had the same eight 21-inch (533 mm) torpedo tubes as the Farraguts, a full set of reloads was carried. The class was initially equipped with the Mark 11 or Mark 12 torpedo, which were replaced by the Mark 15 beginning in 1938.^[7] The heavy armament proved top-heavy, and aircraft were becoming a greater threat, so during World War II on most of the class, mounts 51 and 54^{[clarification needed]} were replaced with dual-purpose (surface action and air action) twin mounts,^[6] and the original 1.1-inch guns were replaced with 40 mm Bofors and 20 mm Oerlikons. In some ships, mount 52 was replaced by a quadruple 40 mm mount, and mount 53 became a single 5 in/38 cal dual-purpose mount. Additional 40 mm guns were added amidships along with 20 mm weapons. In most ships, four K-gun depth charge throwers were added to augment the as-built pair of depth charge racks. In some cases (DD-357, DD-359, DD-360) late in the war, the torpedo tubes, two K-guns, and one depth charge rack were landed, to accommodate additional light AA armament, for a total of sixteen 40 mm in three quadruple and two twin mounts and four 20 mm in two twin mounts.^[8][9][10]

McDougal, Winslow, and Moffett were among the ships that supported the Roosevelt-Churchill conference at Placentia Bay near Argentia, Newfoundland that resulted in the Atlantic Charter in August 1941. Selfridge and Phelps were in port during the attack on Pearl Harbor on 7 December 1941 and engaged enemy aircraft. The class served in the Battle of the Atlantic, in the Pacific War, and escorted convoys in the Americas. Phelps was at the Battle of the Coral Sea and the Battle of Midway, scuttling the disabled aircraft carrier Lexington with torpedoes at the former battle. Balch rescued survivors of the aircraft carrier Yorktown at Midway. While operating out of Trinidad in the Caribbean, Moffett assisted in sinking two U-boats, U-128 and U-604. Notable engagements for other ships of the class included the invasion of Guadalcanal and the Marianas campaign. By September 1944 the class was concentrated in the Atlantic. Porter was the class's only loss, in the Battle of the Santa Cruz Islands on 26 October 1942. Selfridge lost her bow to a torpedo in the Naval Battle of Vella Lavella on 6 October 1943, but was repaired. McDougal and Winslow were reclassified as AG-126 and AG-127 in September 1945 and modified for anti-kamikaze research in a similar configuration to Gearing-class radar picket destroyers. All except Winslow were scrapped shortly after the war; Winslow remained in service as a training ship until 1950 and was scrapped in 1959. Winslow was the longest serving by far of all destroyers commissioned in the 1930s and the last by far to go to the ship breakers.^[8]

• Somers-class destroyer

 This article incorporates text from the public domain Dictionary of American Naval Fighting Ships.

• Bauer, K. Jack; Roberts, Stephen S. (1991). Register of Ships of the U.S. Navy, 1775-1990: Major Combatants. Westport, Connecticut: Greenwood Press. ISBN 0-313-26202-0.
• Friedman, Norman (2004). US Destroyers: An Illustrated Design History (Revised ed.). Annapolis: Naval Institute Press. ISBN 1-55750-442-3.
• Gardiner, Robert; Chesneau, Roger (1980). Conway's All the World's Fighting Ships 1922-1946. London: Conway Maritime Press. ISBN 0-83170-303-2.
• Silverstone, Paul H. (1965). U.S. Warships of World War II. London: Ian Allan Ltd.
•  This article incorporates text from the public domain Dictionary of American Naval Fighting Ships.

Wikimedia Commons has media related to Porter class destroyers.

• Porter-class destroyers at Destroyer History Foundation
• USS Porter, USS Selfridge, USS McDougal, and USS Winslow General Information Book with as-built data at Destroyer History Foundation
• "Goldplater" destroyers at Destroyer History Foundation
• 1850-ton leader classes at Destroyer History Foundation
• Tin Can Sailors @ Destroyers.org - Porter class destroyer Archived 2015-11-24 at the Wayback Machine
• NavSource Destroyer Photo Index Page