HMCS Gatineau (DDE 236)

The St. Laurent-class destroyer was a class of destroyer escorts that served the Royal Canadian Navy and later the Canadian Forces from the mid-1950s to the mid-1990s.

The displacement or displacement tonnage of a ship is its weight. As the term indicates, it is measured indirectly, using Archimedes' principle, by first calculating the volume of water displaced by the ship, then converting that value into weight. Traditionally, various measurement rules have been in use, giving various measures in long tons. Today, tonnes are more commonly used.

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.

The draft or draught of a ship's hull is the vertical distance between the waterline and the bottom of the hull (keel). The draught of the vessel is the maximum depth of any part of the vessel, including appendages such as rudders, propellers and drop keels if deployed. Draft determines the minimum depth of water a ship or boat can safely navigate. The related term air draft is the maximum height of any part of the vessel above the water.

Babcock & Wilcox is an American energy technology and service provider that is active and has operations in many international markets across the globe with its headquarters in Akron, Ohio, USA. Historically, the company is best known for their steam boilers.

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.

Limbo, or Anti Submarine Mortar Mark 10, was the final development of the forward-throwing anti-submarine weapon Squid, designed during the Second World War and was developed by the Admiralty Underwater Weapons Establishment in the 1950s.

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 RUR-5 ASROC is an all-weather, all sea-conditions anti-submarine missile system. Developed by the United States Navy in the 1950s, it was deployed in the 1960s, updated in the 1990s, and eventually installed on over 200 USN surface ships, specifically cruisers, destroyers, and frigates. The ASROC has been deployed on scores of warships of many other navies, including Canada, Germany, Italy, Japan, the Republic of China, Greece, Pakistan and others.

The Mark 44 torpedo is a now-obsolete air-launched and ship-launched lightweight torpedo manufactured in the United States, and under licence in Canada, France, Italy, Japan and the United Kingdom, with 10,500 being produced for U.S. service. It was superseded by the Mark 46 torpedo, beginning in the late 1960s. The Royal Australian Navy, however, continued to use it alongside its successor for a number of years, because the Mark 44 was thought to have superior performance in certain shallow-water conditions.

The Mark 46 torpedo is the backbone of the United States Navy's lightweight anti-submarine warfare torpedo inventory and is the NATO standard. These aerial torpedoes are designed to attack high-performance submarines. In 1989, an improvement program for the Mod 5 to the Mod 5A and Mod 5A(S) increased its shallow-water performance. The Mark 46 was initially developed as Research Torpedo Concept I, one of several weapons recommended for implementation by Project Nobska, a 1956 summer study on submarine warfare.

The Gatineau River is a river in western Quebec, Canada, which rises in lakes north of the Baskatong Reservoir and flows south to join the Ottawa River at the city of Gatineau, Quebec. The river is 386 kilometres (240 mi) long and drains an area of 23,700 square kilometres (9,200 sq mi).

Quebec is one of the thirteen provinces and territories of Canada. It is the largest province by area and the second-largest by population. Much of the population lives in urban areas along the St. Lawrence River, between the most populous city, Montreal, and the provincial capital, Quebec City. Quebec is the home of the Québécois nation. Located in Central Canada, the province shares land borders with Ontario to the west, Newfoundland and Labrador to the northeast, New Brunswick to the southeast, and a coastal border with Nunavut; in the south it borders Maine, New Hampshire, Vermont, and New York in the United States.

Laying the keel or laying down is the formal recognition of the start of a ship's construction. It is often marked with a ceremony attended by dignitaries from the shipbuilding company and the ultimate owners of the ship.

Davie Shipbuilding is a historic shipbuilding company located in Lauzon, Quebec, Canada. The facility is now operating as Chantier Davie Canada Inc. and is the oldest continually operating shipbuilder in North America.

Halifax is the capital and largest municipality of the Canadian province of Nova Scotia, and the largest municipality in Atlantic Canada. Halifax is one of Canada's fastest growing municipalities, and as of 2022, it is estimated that the CMA population of Halifax was 480,582, with 348,634 people in its urban area. The regional municipality consists of four former municipalities that were amalgamated in 1996: Halifax, Dartmouth, Bedford, and Halifax County.

HMCS St. Croix was a Restigouche-class destroyer that served in the Royal Canadian Navy and later the Canadian Forces from 1958 to 1974. The fourth ship commissioned in the class, she was the second ship to bear the name. Following her decommissioning, the ship was used as a training ship at Halifax, Nova Scotia until 1991, when St. Croix was sold for scrapping.

HMCS Kootenay was a Restigouche-class destroyer escort that served in the Royal Canadian Navy and Canadian Forces from 1959 until 1996. She was the fifth ship in her class and the second vessel to carry the designation HMCS Kootenay. The ship suffered two serious incidents in her career: a 1969 explosion and ensuing fire that killed nine, and a 1989 collision that required the complete replacement of her bow. Following her service, the ship was sunk as an artificial reef.

Dom Henrique of Portugal, Duke of Viseu, better known as Prince Henry the Navigator, was a central figure in the early days of the Portuguese Empire and in the 15th-century European maritime discoveries and maritime expansion. Through his administrative direction, he is regarded as the main initiator of what would be known as the Age of Discovery. Henry was the fourth child of King Dom John I of Portugal, who founded the House of Aviz.

Lisbon is the capital and largest city of Portugal, with an estimated population of 544,851 within its administrative limits in an area of 100.05 km2. Lisbon's urban area extends beyond the city's administrative limits with a population of around 2.7 million people, being the 11th-most populous urban area in the European Union. About 3 million people live in the Lisbon metropolitan area, making it the third largest metropolitan area in the Iberian Peninsula, after Madrid and Barcelona. It represents approximately 27% of the country's population. It is mainland Europe's westernmost capital city and the only one along the Atlantic coast. Lisbon lies in the western Iberian Peninsula on the Atlantic Ocean and the River Tagus. The westernmost portions of its metro area, the Portuguese Riviera, form the westernmost point of Continental Europe, culminating at Cabo da Roca.

The Canadair CP-107 Argus is a maritime patrol aircraft designed and manufactured by Canadair for the Royal Canadian Air Force (RCAF). In its early years, the Argus was reputedly the finest anti-submarine patrol bomber in the world. The Argus served throughout the Cold War in the RCAF's Maritime Air Command and later the Canadian Force's Maritime Air Group and Air Command.