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HMNZS Matai (T01)
HMNZS ''Matai'' (T01) was a Marine Department (New Zealand), Marine Department lighthouse tender which was requisitioned by the Royal New Zealand Navy (RNZN) and converted into a Minesweeper (ship), minesweeper. Operational history ''Matai'' was the government's lighthouse tender servicing the marine lights around New Zealand and offshore islands, and had been used for cable laying in the 1930s. She was named after a native Prumnopitys taxifolia, tree. She was requisitioned on 3 March 1941 and handed over to a dockyard for conversion. After commissioning on 1 April 1941, ''Matai'' took over as the flotilla leader of the Minesweepers of the Royal New Zealand Navy#The 25th Minesweeping Flotilla, 25th Minesweeping Flotilla from ''Muritai'' and the flotilla began clearing a German minefield in the Hauraki Gulf. See also *Minesweepers of the Royal New Zealand Navy References * McDougall, R J (1989) ''New Zealand Naval Vessels.'' Page 69–78. Government Printing Office. Further r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island country by area, covering . New Zealand is about east of Australia across the Tasman Sea and south of the islands of New Caledonia, Fiji, and Tonga. The country's varied topography and sharp mountain peaks, including the Southern Alps, owe much to tectonic uplift and volcanic eruptions. New Zealand's capital city is Wellington, and its most populous city is Auckland. The islands of New Zealand were the last large habitable land to be settled by humans. Between about 1280 and 1350, Polynesians began to settle in the islands and then developed a distinctive Māori culture. In 1642, the Dutch explorer Abel Tasman became the first European to sight and record New Zealand. In 1840, representatives of the United Kingdom and Māori chiefs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sonar
Sonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigation, navigate, measure distances (ranging), communicate with or detect objects on or under the surface of the water, such as other vessels. "Sonar" can refer to one of two types of technology: ''passive'' sonar means listening for the sound made by vessels; ''active'' sonar means emitting pulses of sounds and listening for echoes. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. Acoustic location in air was used before the introduction of radar. Sonar may also be used for robot navigation, and SODAR (an upward-looking in-air sonar) is used for atmospheric investigations. The term ''sonar'' is also used for the equipment used to generate and receive the sound. The acoustic frequencies used in sonar systems vary from very low (infrasonic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oerlikon 20 Mm Cannon
The Oerlikon 20 mm cannon is a series of autocannons, based on an original German Becker Type M2 20 mm cannon design that appeared very early in World War I. It was widely produced by Oerlikon Contraves and others, with various models employed by both Allied and Axis forces during World War II. Many versions of the cannon are still used today. Blowback-operated models History Origins During World War I, the German industrialist Reinhold Becker developed a 20 mm caliber cannon, known now as the 20 mm Becker using the advanced primer ignition blowback (API blowback) method of operation. This used a 20×70mmRB cartridge and had a cyclic rate of fire of 300 rpm. It was used on a limited scale as an aircraft gun on ''Luftstreitkräfte'' warplanes, and an anti-aircraft gun towards the end of that war. Because the Treaty of Versailles banned further production of such weapons in Germany, the patents and design works were transferred in 1919 to the Swiss firm SEMAG (''Seeba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Department (New Zealand)
The New Zealand Marine Department was a government department in New Zealand that managed the administration of marine law. History The New Zealand Marine Department was created in late 1866, initially holding responsibility for the administration of the country's lighthouses. It grew in scope to cover many other responsibilities including overseeing mercantile marine activities and harbour duties, regulating the fisheries industry and the administration of the Ross Dependency. The Marine Department was initially under the ministerial control of the Postmaster-General, until 1870 when it instead became a part of the New Zealand Customs Department. The Marine Department remained a part the Customs Department until 1903 (apart from a minor interlude between 1878 and 1881) when it was made a stand-alone government department. The Shipping and Seamen's Act of 1877 gave the Marine Department statutory recognition and authorised the Governor to appoint both a Minister and a Secretary t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal New Zealand Navy
The Royal New Zealand Navy (RNZN; mi, Te Taua Moana o Aotearoa, , Sea Warriors of New Zealand) is the maritime arm of the New Zealand Defence Force. The fleet currently consists of nine ships. The Navy had its origins in the Naval Defence Act 1913, and the subsequent purchase of the cruiser , which by 1921 had been moored in Auckland as a training ship. A slow buildup occurred during the Interwar period, and then perhaps the infant Navy's finest hour occurred soon after the beginning of World War II when fought alongside two other Royal Navy cruisers at the Battle of the River Plate in December 1939. History Pre–World War I The first recorded maritime combat activity in New Zealand occurred when Māori in war waka attacked Dutch explorer Abel Tasman off the northern tip of the South Island in December 1642. The New Zealand Navy did not exist as a separate military force until 1941. The association of the Royal Navy with New Zealand began with the arrival of Lieutenant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minesweeper (ship)
A minesweeper is a small warship designed to remove or detonate naval mines. Using various mechanisms intended to counter the threat posed by naval mines, minesweepers keep waterways clear for safe shipping. History The earliest known usage of the naval mine dates to the Ming dynasty.Needham, Volume 5, Part 7, 203–205. Dedicated minesweepers, however, only appeared many centuries later during the Crimean War, where they were deployed by the British. The Crimean War minesweepers were rowboats trailing grapnels to snag mines. Minesweeping technology picked up in the Russo-Japanese War, using aging torpedo boats as minesweepers. In Britain, naval leaders recognized before the outbreak of World War I that the development of sea mines was a threat to the nation's shipping and began efforts to counter the threat. Sir Arthur Wilson noted the real threat of the time was blockade aided by mines and not invasion. The function of the fishing fleet's trawlers with their trawl gear was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prumnopitys Taxifolia
''Prumnopitys taxifolia'', the mataī ( mi, mataī) or black pine, is an endemic New Zealand coniferous tree that grows on the North Island and South Island. It also occurs on Stewart Island/Rakiura (47 °S) but is uncommon there. It grows up to 40 m high, with a trunk up to 2 m diameter. The leaves are linear to sickle-shaped, 10–15 mm long and 1.5–2 mm broad. The seed cones are highly modified, reduced to a central stem 3–4 cm long bearing 1-6 scales, each scale maturing berry-like, 10–15 mm long, violet-purple with a soft edible pulp covering the single seed. The seeds are dispersed by the New Zealand pigeon (kererū), which eats the 'berries' and passes the seeds in its droppings. Classification The scientific name ''taxifolia'' derives from the resemblance of the leaves to those of the yew (''Taxus''). In the past the species, like the other species of ''Prumnopitys'', was often included in ''Podocarpus''; in this species under the name ''Podo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minesweepers Of The Royal New Zealand Navy
Commissioned minesweepers and danlayers of the Royal New Zealand Navy (RNZN) from its formation on 1 October 1941 to the present. The RNZN was created two years into World War II. For coherence this article covers the war years from the start, and thus includes also the New Zealand minesweepers operating from the beginning of the war. World War II minesweepers During World War II the RNZN operated 39 minesweepers and danlayers. This included 20 naval trawlers (13 , three and four ), five converted trawlers, 10 converted merchant boats, and four danlayers. Naval trawlers Naval trawlers were trawlers purpose built to Admiralty specification to operate as minesweepers and/or anti-submarine boats. Castle class Thirteen naval trawlers were commissioned. Apart from ''James Cosgrove'' and ''Wakakura'', all were built in New Zealand by government directive, circa 1942. They were long, displaced 540 tons standard or 612 tons loaded, and were designed for a complement of 27. The three ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hauraki Gulf
The Hauraki Gulf / Tīkapa Moana is a coastal feature of the North Island of New Zealand. It has an area of 4000 km2, Zeldisl, J. R. et al. (1995) Salp grazing: effects on phytoplankton abundance, vertical distribution and taxonomic composition in a coastal habitat. Marine Ecology Progress Series, Vol. 126, p 267-283 and lies between, in anticlockwise order, the , the Hauraki Plains, the , and [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lighthouse Tenders Of New Zealand
A lighthouse is a tower, building, or other type of physical structure designed to emit light from a system of lamps and lenses and to serve as a beacon for navigational aid, for maritime pilots at sea or on inland waterways. Lighthouses mark dangerous coastlines, hazardous shoals, reefs, rocks, and safe entries to harbors; they also assist in aerial navigation. Once widely used, the number of operational lighthouses has declined due to the expense of maintenance and has become uneconomical since the advent of much cheaper, more sophisticated and effective electronic navigational systems. History Ancient lighthouses Before the development of clearly defined ports, mariners were guided by fires built on hilltops. Since elevating the fire would improve the visibility, placing the fire on a platform became a practice that led to the development of the lighthouse. In antiquity, the lighthouse functioned more as an entrance marker to ports than as a warning signal for reefs and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
