Japanese destroyer Nowaki (1940)

The Asashio-class destroyers were a class of ten destroyers of the Imperial Japanese Navy in service before and during World War II. The overall layout of the class proved successful in service and created a powerful ship that served as the basis for the design of the following two classes of destroyers.

Length overall is the maximum length of a vessel's hull measured parallel to the waterline. This length is important while docking the ship. It is the most commonly used way of expressing the size of a ship, and is also used for calculating the cost of a marina berth.

The beam of a ship is its width at its widest point. The maximum beam (BMAX) is the distance between planes passing through the outer extremities of the ship, beam of the hull (BH) only includes permanently fixed parts of the hull, and beam at waterline (BWL) is the maximum width where the hull intersects the surface of the water.

A steam turbine is a machine that extracts thermal energy from pressurized steam and uses it to do mechanical work on a rotating output shaft. Its modern manifestation was invented by Charles Parsons in 1884. Fabrication of a modern steam turbine involves advanced metalwork to form high-grade steel alloys into precision parts using technologies that first became available in the 20th century; continued advances in durability and efficiency of steam turbines remains central to the energy economics of the 21st century.

The knot is a unit of speed equal to one nautical mile per hour, exactly 1.852 km/h. The ISO standard symbol for the knot is kn. The same symbol is preferred by the Institute of Electrical and Electronics Engineers (IEEE), while kt is also common, especially in aviation, where it is the form recommended by the International Civil Aviation Organization (ICAO). The knot is a non-SI unit. The knot is used in meteorology, and in maritime and air navigation. A vessel travelling at 1 knot along a meridian travels approximately one minute of geographic latitude in one hour.

The 12.7 cm/50 Type 3 naval gun was a medium-caliber naval gun of the Imperial Japanese Navy used during World War II. It was the standard weapon for Japanese destroyers between 1928 and 1944. It has been credited as a true dual-purpose gun, but this was more a nominal capability than real, as its bag propellant and need for hand ramming required the gun to be loaded at elevation angles of 5–10°. This dropped its rate of fire to a relatively slow 5–10 rounds per minute, and its training speed of only 6° per second meant that it had a great deal of difficulty engaging enemy aircraft with any chance of success. After the end of World War II the gun remained in service on the two Japanese destroyers ceded to the Soviet Union and the Republic of China as war reparations.

A gun turret is a mounting platform from which weapons can be fired that affords protection, visibility and ability to turn and aim. A modern gun turret is generally a rotatable weapon mount that houses the crew or mechanism of a projectile-firing weapon and at the same time lets the weapon be aimed and fired in some degree of azimuth and elevation.

Superfiring armament is a naval military building technique in which two turrets are located in a line, one behind the other, with the second turret located above ("super") the one in front so that the second turret can fire over the first. This configuration meant that both forward or aft turrets could fire at any target within their sector, even when the target was in the same vertical plane as the turrets.

A superstructure is an upward extension of an existing structure above a baseline. This term is applied to various kinds of physical structures such as buildings, bridges, or ships.

A depth charge is an anti-submarine warfare (ASW) weapon. It is intended to destroy a submarine by being dropped into the water nearby and detonating, subjecting the target to a powerful and destructive hydraulic shock. Most depth charges use high explosive charges and a fuze set to detonate the charge, typically at a specific depth. Depth charges can be dropped by ships, patrol aircraft, and helicopters.

The term "British Malaya" loosely describes a set of states on the Malay Peninsula and the island of Singapore that were brought under British hegemony or control between the late 18th and the mid-20th century. Unlike the term "British India", which excludes the Indian princely states, British Malaya is often used to refer to the Federated and the Unfederated Malay States, which were British protectorates with their own local rulers, as well as the Straits Settlements, which were under the sovereignty and direct rule of the British Crown, after a period of control by the East India Company.

A cruiser is a type of warship. Modern cruisers are generally the largest ships in a fleet after aircraft carriers and amphibious assault ships, and can usually perform several roles.

Maya (摩耶) was one of four Takao-class heavy cruisers, active in World War II with the Imperial Japanese Navy (IJN). These were the largest and most modern cruisers in the Japanese fleet, and were intended to form the backbone of a multipurpose long-range strike force. These ships were fast, powerful and heavily armed, with enough firepower to hold their own against any cruiser in any other navy in the world. Her sister ships were Takao, Atago and Chōkai.

Atago (愛宕) was the second vessel in the Takao-class heavy cruisers, active in World War II with the Imperial Japanese Navy (IJN). These were among the largest and most modern cruisers in the Japanese fleet, designed with the intention to form the backbone of a multipurpose long-range strike force. Her sister ships were Takao, Maya and Chōkai.

Takao (高雄) was the lead vessel in the Takao-class heavy cruisers, active in World War II with the Imperial Japanese Navy. These were the largest cruisers in the Japanese fleet, and were intended to form the backbone of a multipurpose long-range strike force. Her sister ships were Atago, Maya and Chōkai.

Arashi (嵐, "Storm") was a Kagerō-class destroyer of the Imperial Japanese Navy.

The Allies, formally referred to as the United Nations from 1942, were an international military coalition formed during the Second World War (1939–1945) to oppose the Axis powers, led by Nazi Germany, Imperial Japan, and Fascist Italy. Its principal members by the end of 1941 were the United Kingdom, United States, Soviet Union, and China.

HMS Stronghold was an S-class destroyer, which served with the Royal Navy during the Second World War. The ship was one of the first vehicles to deploy an unmanned aircraft. Launched on 6 May 1919, the destroyer was fitted with a simple catapult in 1924, which used a bag of sand as a weight, and launched the RAE 1921 Target, an early form of unmanned aircraft. A more sophisticated cordite catapult was fitted in 1927 and used to launch the more advanced RAE Larynx. In total, more than twenty test flights were undertaken before the catapult was removed. The destroyer was subsequently fitted out as a minelayer. At the start of the Second World War, the destroyer was based in Singapore. Stronghold helped to rescue the Supermarine Walrus from the battlecruiser Repulse, which had been sunk by the Japanese, in 1941 and, the following year, towed the destroyer Vendetta on the first part of the Royal Australian Navy vessel's journey to Fremantle. On 2 March 1942, the vessel was spotted by a Japanese reconnaissance seaplane and attacked by the heavy cruiser Maya, along with the two escorting destroyers Arashi and Nowaki. Heavily outgunned, the destroyer was sunk with the loss of nine officers and sixty-one ratings.

HMAS Yarra (U77), named for the Yarra River, was a Grimsby-class sloop of the Royal Australian Navy (RAN) that served during World War II. Commissioned in 1936, Yarra spent the early part of the war in Australian waters, then was transferred to the East Indies Station in 1940. The sloop operated in the Red Sea, then was involved in the Anglo-Iraqi War and the Anglo-Soviet invasion of Iran. After operating as part of the Tobruk Ferry Service in the Mediterranean during November, Yarra was reassigned to Southeast Asia in response to Japanese attacks. On 4 March 1942, Yarra was attacked and sunk by a force of Japanese cruisers and destroyers while attempting to protect ships withdrawing to Australia.

An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and facilities for carrying, arming, deploying, and recovering aircraft. Typically, it is the capital ship of a fleet, as it allows a naval force to project air power worldwide without depending on local bases for staging aircraft operations. Carriers have evolved since their inception in the early twentieth century from wooden vessels used to deploy balloons to nuclear-powered warships that carry numerous fighters, strike aircraft, helicopters, and other types of aircraft. While heavier aircraft such as fixed-wing gunships and bombers have been launched from aircraft carriers, these aircraft have not landed on a carrier. By its diplomatic and tactical power, its mobility, its autonomy and the variety of its means, the aircraft carrier is often the centerpiece of modern combat fleets. Tactically or even strategically, it replaced the battleship in the role of flagship of a fleet. One of its great advantages is that, by sailing in international waters, it does not interfere with any territorial sovereignty and thus obviates the need for overflight authorizations from third-party countries, reduces the times and transit distances of aircraft and therefore significantly increase the time of availability on the combat zone.

Akagi was an aircraft carrier built for the Imperial Japanese Navy (IJN), named after Mount Akagi in present-day Gunma Prefecture. Though she was laid down as an Amagi-class battlecruiser, Akagi was converted to an aircraft carrier while still under construction to comply with the terms of the Washington Naval Treaty. The ship was rebuilt from 1935 to 1938 with her original three flight decks consolidated into a single enlarged flight deck and an island superstructure. The second Japanese aircraft carrier to enter service, and the first large or "fleet" carrier, Akagi and the related Kaga figured prominently in the development of the IJN's new carrier striking force doctrine that grouped carriers together, concentrating their air power. This doctrine enabled Japan to attain its strategic goals during the early stages of the Pacific War from December 1941 until mid-1942.

Chuuk Lagoon, previously Truk Atoll, is an atoll in the central Pacific. It lies about 1,800 kilometres northeast of New Guinea, and is part of Chuuk State within the Federated States of Micronesia (FSM). A protective reef, 225 kilometres (140 mi) around, encloses a natural harbour 79 by 50 km, with an area of 2,130 km2 (820 sq mi). It has a land area of 93.07 square kilometres, with a population of 36,158 people and a maximal elevation of 443 metres (1,453 ft). Weno city on Moen Island functions as both the atoll's capital and the state capital, and is the largest city in the FSM with its 13,700 people.