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Navigational Aids
A navigational aid (NAVAID), also known as aid to navigation (ATON), is any sort of signal, markers or guidance equipment which aids the traveler in navigation, usually nautical or aviation travel. Common types of such aids include lighthouses, buoys, fog signals, and day beacons. Definition According to the glossary of terms in the United States Coast Guard Light list, an ''aid to navigation'' (ATON) is any device external to a vessel or aircraft specifically intended to assist navigators in determining their position or safe course, or to warn them of dangers or obstructions to navigation. Lateral marks Lateral marks indicate the edge of the channel. The standards are defined by the International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA). Approaching harbour port a vessel leaves port hand marks to port (left) and starboard hand marks to starboard (right). Port hand marks are cylindrical, starboard marks are conical. If the mark is a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quokka 1, Fremantle, 2020 (06)
The quokka (; ''Setonix brachyurus'') is a small Macropodidae, macropod about the size of a Cat, domestic cat. It is the Monotypic, only member of the genus ''Setonix''. Like other marsupials in the macropod family (such as kangaroos and Wallaby, wallabies), the quokka is herbivorous and mainly nocturnal. The quokka's range is a small area of southwestern Australia. They inhabit some smaller islands off the coast of Western Australia, particularly Rottnest Island just off Perth and Bald Island near Albany, Western Australia, Albany. Isolated, scattered populations also exist in forest and coastal heath between Perth and Albany. A small colony inhabits a protected area of Two Peoples Bay Nature Reserve, where they co-exist with the critically endangered Gilbert's potoroo. Description A quokka weighs and is long with a tail, which is quite short for a macropod. It has a stocky build, well developed hind legs, rounded ears, and a short, broad head. Although looking rather li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Navigational Chart
A nautical chart or hydrographic chart is a graphic representation of a sea region or water body and adjacent coasts or banks. Depending on the scale of the chart, it may show depths of water (bathymetry) and heights of land (topography), natural features of the seabed, details of the coastline, navigational hazards, locations of natural and human-made aids to navigation, information on tides and currents, local details of the Earth's magnetic field, and human-made structures such as harbours, buildings, and bridges. Nautical charts are essential tools for marine navigation; many countries require vessels, especially commercial ships, to carry them. Nautical charting may take the form of charts printed on paper (raster navigational charts) or computerized electronic navigational charts. Recent technologies have made available paper charts which are printed "on demand" with cartographic data that has been downloaded to the commercial printing company as recently as the night ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Landmark
A landmark is a recognizable natural or artificial feature used for navigation, a feature that stands out from its near environment and is often visible from long distances. In modern-day use, the term can also be applied to smaller structures or features that have become local or national symbols. Etymology In Old English, the word ''landmearc'' (from ''land'' + ''mearc'' (mark)) was used to describe a boundary marker, an "object set up to mark the boundaries of a kingdom, estate, etc." Starting around 1560, this interpretation of "landmark" was replaced by a more general one. A landmark became a "conspicuous object in a landscape". A ''landmark'' literally meant a geographic feature used by explorers and others to find their way back to their departure point, or through an area. For example, Table Mountain near Cape Town, South Africa, was used as a landmark to help sailors navigate around the southern tip of Africa during the Age of Exploration. Artificial structures ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Global Positioning System
The Global Positioning System (GPS) is a satellite-based hyperbolic navigation system owned by the United States Space Force and operated by Mission Delta 31. It is one of the global navigation satellite systems (GNSS) that provide geolocation and time information to a GPS receiver anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites. It does not require the user to transmit any data, and operates independently of any telephone or Internet reception, though these technologies can enhance the usefulness of the GPS positioning information. It provides critical positioning capabilities to military, civil, and commercial users around the world. Although the United States government created, controls, and maintains the GPS system, it is freely accessible to anyone with a GPS receiver. Overview The GPS project was started by the U.S. Department of Defense in 1973. The first prototype spacecraft was launched in 1978 an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foghorn
A foghorn or fog signal is a device that uses sound to warn vehicles of navigational hazards such as rocky coastlines, or boats of the presence of other vessels, in foggy conditions. The term is most often used in relation to marine transport. When visual navigation aids such as lighthouses are obscured, foghorns provide an audible warning of rock outcrops, shoals, headlands, or other dangers to shipping. Description All foghorns use a vibrating column of air to create an audible tone, but the method of setting up this vibration differs. Some horns, such as the Daboll trumpet, used vibrating plates or metal reed (music), reeds, a similar principle to a modern electric Vehicle horn, car horn. Others used air forced through holes in a rotating cylinder or disk, in the same manner as a siren (alarm), siren. Semi-automatic operation of foghorns was achieved by using a clockwork mechanism (or "coder") to sequentially open the valves admitting air to the horns; each horn was given its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Distance Measuring Equipment
In aviation, distance measuring equipment (DME) is a radio navigation technology that measures the slant range (distance) between an aircraft and a ground station by timing the propagation delay of radio signals in the frequency band between 960 and 1215 megahertz (MHz). Line-of-visibility between the aircraft and ground station is required. An interrogator (airborne) initiates an exchange by transmitting a pulse pair, on an assigned 'channel', to the transponder ground station. The channel assignment specifies the carrier frequency and the spacing between the pulses. After a known delay, the transponder replies by transmitting a pulse pair on a frequency that is offset from the interrogation frequency by 63 MHz and having specified separation.''Annex 10 to the Convention on International Civil Aviation, Volume I – Radio Navigation Aids''; International Civil Aviation Organization; International Standards and Recommended Practices. DME systems are used worldwide, usi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daymark
A daymark is a navigational aid for sailors and maritime pilot, pilots, distinctively marked to maximize its visibility in daylight. The word is also used in a more specific, technical sense to refer to a signboard or daytime identifier that is attached to a day beacon or other aid to navigation. In that sense, a daymark conveys to the mariner during daylight hours the same significance as the aid's light or reflector does at night. Standard signboard shapes are square, triangular, and rectangular, while the standard colours are red, green, orange, yellow, and black. Notable daymarks * Trinity House Obelisk, UK * Kingswear Daymark, UK * Tasku beacon tower, Finland * Keskiniemi beacon tower, Finland * Hiidenniemi beacon tower, Finland * Laitakari beacon tower, Finland * Herring Tower, Langness, Isle of Man * Le Hocq, Jersey * La Tour Cârrée, Jersey * Scharhörnbake, Germany Symbols used on US charts Chart symbols used by the US National Oceanic and Atmospheric Administrati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buoy
A buoy (; ) is a buoyancy, floating device that can have many purposes. It can be anchored (stationary) or allowed to drift with ocean currents. History The ultimate origin of buoys is unknown, but by 1295 a seaman's manual referred to navigation buoys in the Guadalquivir River in Spain. To the north there are early medieval mentions of the French / Belgian River Meuse, Maas being buoyed. Such early buoys were probably just timber beams or rafts, but in 1358 there is a record of a barrel buoy in the Dutch Maasmond (also known as the Maas Sluis or Maasgat). The simple barrel was difficult to secure to the seabed, and so a conical ''tonne'' was developed. They had a solid plug at the narrow end through which a mooring ring could be attached. By 1790 the older conical tonne was being replaced by a ''nun'' buoy. This had the same conical section below the waterline as the tonne buoy, but at the waterline a barrel shape was used to allow a truncated cone to be above the water. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
USCG Aids To Navigation Boat
The United States Coast Guard maintains roughly 145 Aids to Navigation Boats. These boats were designed primarily to serve within the inland waters of the United States. These vessels include TANB/BUSL/ATON/ANB ranging from 16 to 55 feet in length. Most Aids to Navigation Boats of the United States Coast Guard are stationed with Aids to Navigation Teams (ANT). These are teams of boatswain's mates, machinery technicians, electrician's mates, and non-rated personnel that service small buoys, jetty lights and lighthouses. Boats *65-ft Aids to Navigation Boat (ANB) Similar to the 55 ft ANB, there are 2 boats, one is in Galveston, Texas (65402). The additional ten feet is added to the pilothouse and crew quarters. It has a higher capacity crane, with a longer reach and a large "V" cut into the stern platform to allow the boat to more readily maintain contact with an aid even under wave conditions. It is powered by two 825 hp DD 12V71TA two stroke diesel engines and has a 7.5 kW ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tasmania
Tasmania (; palawa kani: ''Lutruwita'') is an island States and territories of Australia, state of Australia. It is located to the south of the Mainland Australia, Australian mainland, and is separated from it by the Bass Strait. The state encompasses the main island of Tasmania, the List of islands by area#Islands, 26th-largest island in the world, and the List of islands of Tasmania, surrounding 1000 islands. It is Australia's smallest and least populous state, with 573,479 residents . The List of Australian capital cities, state capital and largest city is Hobart, with around 40% of the population living in the Greater Hobart area. Estimated resident population, 30 June 2017. Tasmania is the most decentralised state in Australia, with the lowest proportion of its residents living within its capital city. Tasmania's main island was first inhabited by Aboriginal Australians, Aboriginal peoples, who today generally identify as Palawa or Pakana. It is believed that Abori ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
