Flying boat in the context of "Air-sea rescue"

Ascension Island is an isolated volcanic island, 7°56′ south of the Equator in the South Atlantic Ocean. It is about 960 miles (1,540 km) from the coast of Africa and 1,400 miles (2,300 km) from the coast of South America. It is governed as part of the British Overseas Territory of Saint Helena, Ascension and Tristan da Cunha, of which the main island, Saint Helena, is around 800 miles (1,300 km) to the southeast. The territory also includes the sparsely populated Tristan da Cunha archipelago, 2,000 miles (3,200 km) to the south, about halfway to the Antarctic Circle.

Ascension Island was possibly discovered by the Portuguese seafarer João da Nova in 1501, before being named Ascension by Afonso de Albuquerque in 1503 on Ascension Day. Ascension Island was garrisoned by the British Admiralty from 22 October 1815 to 1922 and was an important refuelling stop for ships and commercial airliners in the days of international air travel by flying boats. During World War II, it was an important naval and air station, especially providing antisubmarine warfare bases in the Battle of the Atlantic.

A hull is the watertight body of a ship, boat, submarine, or flying boat. The hull may open at the top (such as a dinghy), or it may be fully or partially covered with a deck. Atop the deck may be a deckhouse and other superstructures, such as a funnel, derrick, or mast. The line where the hull meets the water surface is called the waterline.

A seaplane is a powered fixed-wing aircraft capable of taking off and landing (alighting) on water. Seaplanes are usually divided into two categories based on their technological characteristics: floatplanes and flying boats; the latter are generally far larger and can carry far more. Seaplanes that can also take off and land on airfields are in a subclass called amphibious aircraft, or amphibians. Seaplanes were sometimes called hydroplanes, but currently this term applies instead to motor-powered watercraft that use the technique of hydrodynamic lift to skim the surface of water when running at speed.

The use of seaplanes gradually tapered off after World War II, partially because of the investments in airports during the war but mainly because landplanes were less constrained by weather conditions that could result in sea states being too high to operate seaplanes while landplanes could continue to operate. In the 21st century, seaplanes maintain a few niche uses, such as for aerial firefighting, air transport around archipelagos, and access to undeveloped or roadless areas, some of which have numerous lakes. In British English, seaplane is sometimes used specifically to refer to a floatplane, rather than a flying boat.

A reconnaissance aircraft (colloquially, a spy plane) is a military aircraft designed or adapted to perform aerial reconnaissance with roles including collection of imagery intelligence (including using photography), signals intelligence, as well as measurement and signature intelligence. Modern technology has also enabled some aircraft and UAVs to carry out real-time surveillance in addition to general intelligence gathering.

Before the development of devices such as radar, military forces relied on reconnaissance aircraft for visual observation and scouting of enemy movement. An example is the PBY Catalina maritime patrol flying boat used by the Allies in World War II: a flight of U.S. Navy Catalinas spotted part of the Japanese fleet approaching Midway Island, beginning the Battle of Midway.

The Grumman HU-16 Albatross is a large, twin-radial engined amphibious flying boat that was used by the United States Air Force (USAF), the U.S. Navy (USN), the U.S. Coast Guard (USCG), and the Royal Canadian Air Force primarily as a search and rescue (SAR) aircraft. Originally designated as the SA-16 for the USAF and the JR2F-1 and UF-1 for the USN and USCG, it was redesignated as the HU-16 in 1962.

In aviation, a water landing is, in the broadest sense, an aircraft landing on a body of water. Seaplanes, such as floatplanes and flying boats, land on water as a normal operation. Ditching is a controlled emergency landing on the water surface in an aircraft not designed for the purpose, and it is a very rare occurrence. Controlled flight into the surface and uncontrolled flight ending in a body of water (including a runway excursion into water) are generally not considered water landings or ditching, but are considered accidents. Most times, ditching results in aircraft structural failure.