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VOLMET
{{Use dmy dates, date=December 2021 VOLMET (French origin ''vol'' (flight) and ''météo'' (weather report)), or meteorological information for aircraft in flight, is a worldwide network of radio stations that broadcast TAF, SIGMET and METAR reports on shortwave frequencies, and in some countries on VHF too. Reports are sent in upper sideband mode, using automated voice transmissions. Pilots on international routes, such as North Atlantic Tracks, use these transmissions to avoid storms and turbulence, and to determine which procedures to use for descent, approach, and landing. The VOLMET network divides the world into specific regions, and individual VOLMET stations in each region broadcast weather reports for specific groups of air terminals in their region at specific times, coordinating their transmission schedules so as not to interfere with one another. Schedules are determined in intervals of five minutes, with one VOLMET station in each region broadcasting reports ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
VOLMET X25,55 In 6617kHz
{{Use dmy dates, date=December 2021 VOLMET (French origin ''vol'' (flight) and ''météo'' (weather report)), or meteorological information for aircraft in flight, is a worldwide network of radio stations that broadcast TAF, SIGMET and METAR reports on shortwave frequencies, and in some countries on VHF too. Reports are sent in upper sideband mode, using automated voice transmissions. Pilots on international routes, such as North Atlantic Tracks, use these transmissions to avoid storms and turbulence, and to determine which procedures to use for descent, approach, and landing. The VOLMET network divides the world into specific regions, and individual VOLMET stations in each region broadcast weather reports for specific groups of air terminals in their region at specific times, coordinating their transmission schedules so as not to interfere with one another. Schedules are determined in intervals of five minutes, with one VOLMET station in each region broadcasting repor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SIGMET
SIGMET, or Significant Meteorological Information (AIM 7-1-6), is a severe weather advisory that contains meteorological information concerning the safety of all aircraft. Compared to AIRMETs, SIGMETs cover more severe weather. Types There are three main types of internationally recognized SIGMETs per ICAO: * Volcanic ash (VA or WV SIGMET) * Tropical Cyclone (TC SIGMET) * Other En-route weather phenomenon (WS SIGMET), which may consist of ** Thunderstorm types ** Turbulences types ** Mountain waves ** Icing/Sleet/Hail ** Dust or sand storms ** Radioactive Cloud This information is usually broadcast on the ATIS at ATC facilities, as well as over VOLMET stations. They are assigned an alphabetic designator from N through Y (excluding S and T). SIGMETs are issued as needed, and are valid up to four hours. SIGMETS for hurricanes and volcanic ash outside the CONUS are valid up to six hours. Convective SIGMETs For airmen in the U.S., there is an additional category of SIGMET kn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
METAR
METAR is a format for reporting weather information. A METAR weather report is predominantly used by aircraft pilots, and by meteorologists, who use aggregated METAR information to assist in weather forecasting. Raw METAR is the most common format in the world for the transmission of observational weather data. It is highly standardized through the International Civil Aviation Organization (ICAO), which allows it to be understood throughout most of the world. Report names The United States Federal Aviation Administration (FAA) in its publication the Aeronautical Information Manual describes the report as ''aviation routine weather report'' while the international authority for the code form, the World Meteorological Organization (WMO), describes it as the ''aerodrome routine meteorological report.'' The National Oceanic and Atmospheric Administration (part of the United States Department of Commerce) and the United Kingdom's Met Office both employ the definition used by the FAA. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raf Wolmet
The Royal Air Force (RAF) is the United Kingdom's air and space force. It was formed towards the end of the First World War on 1 April 1918, becoming the first independent air force in the world, by regrouping the Royal Flying Corps (RFC) and the Royal Naval Air Service (RNAS). Following the Allied victory over the Central Powers in 1918, the RAF emerged as the largest air force in the world at the time. Since its formation, the RAF has taken a significant role in British military history. In particular, it played a large part in the Second World War where it fought its most famous campaign, the Battle of Britain. The RAF's mission is to support the objectives of the British Ministry of Defence (MOD), which are to "provide the capabilities needed to ensure the security and defence of the United Kingdom and overseas territories, including against terrorism; to support the Government's foreign policy objectives particularly in promoting international peace and security". The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gender Volmet Canada
Gender is the range of characteristics pertaining to femininity and masculinity and differentiating between them. Depending on the context, this may include sex-based social structures (i.e. gender roles) and gender identity. Most cultures use a gender binary, in which gender is divided into two categories, and people are considered part of one or the other (boys/men and girls/women);Kevin L. Nadal, ''The SAGE Encyclopedia of Psychology and Gender'' (2017, ), page 401: "Most cultures currently construct their societies based on the understanding of gender binary—the two gender categorizations (male and female). Such societies divide their population based on biological sex assigned to individuals at birth to begin the process of gender socialization." those who are outside these groups may fall under the umbrella term ''non-binary''. Some societies have specific genders besides "man" and "woman", such as the hijras of South Asia; these are often referred to as ''third gende ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Network
There are two types of radio network currently in use around the world: the one-to-many (simplex communication) broadcast network commonly used for public information and mass-media entertainment, and the two-way radio ( duplex communication) type used more commonly for public safety and public services such as police, fire, taxicabs, and delivery services. Cell phones are able to send and receive simultaneously by using two different frequencies at the same time. Many of the same components and much of the same basic technology applies to all three. The two-way type of radio network shares many of the same technologies and components as the broadcast-type radio network but is generally set up with fixed broadcast points (transmitters) with co-located receivers and mobile receivers/transmitters or transceivers. In this way both the fixed and mobile radio units can communicate with each other over broad geographic regions ranging in size from small single cities to entire states/prov ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shortwave
Shortwave radio is radio transmission using shortwave (SW) radio frequencies. There is no official definition of the band, but the range always includes all of the high frequency band (HF), which extends from 3 to 30 MHz (100 to 10 metres); above the medium frequency band (MF), to the bottom of the VHF band. Radio waves in the shortwave band can be reflected or refracted from a layer of electrically charged atoms in the atmosphere called the ionosphere. Therefore, short waves directed at an angle into the sky can be reflected back to Earth at great distances, beyond the horizon. This is called skywave or "skip" propagation. Thus shortwave radio can be used for communication over very long distances, in contrast to radio waves of higher frequency, which travel in straight lines (line-of-sight propagation) and are limited by the visual horizon, about 64 km (40 miles). Shortwave broadcasts of radio programs played an important role in the early days of radio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Single-sideband Modulation
In radio communications, single-sideband modulation (SSB) or single-sideband suppressed-carrier modulation (SSB-SC) is a type of modulation used to transmit information, such as an audio signal, by radio waves. A refinement of amplitude modulation, it uses transmitter power and bandwidth more efficiently. Amplitude modulation produces an output signal the bandwidth of which is twice the maximum frequency of the original baseband signal. Single-sideband modulation avoids this bandwidth increase, and the power wasted on a carrier, at the cost of increased device complexity and more difficult tuning at the receiver. Basic concept Radio transmitters work by mixing a radio frequency (RF) signal of a specific frequency, the carrier wave, with the audio signal to be broadcast. In AM transmitters this mixing usually takes place in the final RF amplifier (high level modulation). It is less common and much less efficient to do the mixing at low power and then amplify it in a linear ampl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North Atlantic Tracks
North Atlantic Tracks, officially titled the North Atlantic Organised Track System (NAT-OTS), is a structured set of transatlantic flight routes that stretch from the eastern North America to western Europe across the Atlantic Ocean, within the North Atlantic airspace region. They ensure that aircraft are separated over the ocean, where there is little radar coverage. These heavily travelled routes are used by aircraft flying between North America and Europe, operating between the altitudes of inclusive. Entrance and movement along these tracks is controlled by special oceanic control centres to maintain separation between aircraft. The primary purpose of these routes is to allow air traffic control to effectively separate the aircraft. Because of the volume of NAT traffic, allowing aircraft to choose their own co-ordinates would make the ATC task far more complex. They are aligned in such a way as to minimize any head winds and maximize tail winds impact on the aircraft. This ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Automatic Terminal Information Service
Automatic terminal information service, or ATIS, is a continuous broadcast of recorded aeronautical information in busier terminal areas, i.e. airports and their immediate surroundings. ATIS broadcasts contain essential information, such as current weather information, active runways, available approaches, and any other information required by the pilots, such as important NOTAMs. Pilots usually listen to an available ATIS broadcast before contacting the local control unit, which reduces the controllers' workload and relieves frequency congestion. In the US, ATIS will include (in this order): the airport or facility name; a phonetic letter code; time of the latest weather observation in UTC time; weather information consisting of wind direction and velocity, visibility, obstructions to vision, sky condition, temperature, dew point, altimeter setting, density altitude advisory if appropriate; and other pertinent remarks, including runway in use. If it exists, the weather observatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
