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International Air Space
Airspace is the portion of the atmosphere controlled by a country above its territory, including its territorial waters or, more generally, any specific three-dimensional portion of the atmosphere. It is not the same as outer space which is the expanse or space outside the Earth and aerospace which is the general term for Earth's atmosphere and the outer space within the planet's vicinity. Horizontal boundary By international law, a state "has complete and exclusive sovereignty over the airspace above its territory", which corresponds with the maritime definition of territorial waters as being 12 nautical miles (22.2 km) out from a nation's coastline. Airspace not within any country's territorial limit is considered international, analogous to the "high seas" in maritime law. However, a country may, by international agreement, assume responsibility for controlling parts of international airspace, such as those over the oceans. Such airspace in respect of which a countr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Country
A country is a distinct part of the world, such as a state, nation, or other political entity. When referring to a specific polity, the term "country" may refer to a sovereign state, state with limited recognition, constituent country, or dependent territory. Most sovereign states, but not all countries, are members of the United Nations. There is no universal agreement on the number of "countries" in the world, since several states have disputed sovereignty status or limited recognition, and a number of non-sovereign entities are commonly considered countries. The definition and usage of the word "country" are flexible and have changed over time. '' The Economist'' wrote in 2010 that "any attempt to find a clear definition of a country soon runs into a thicket of exceptions and anomalies." Areas much smaller than a political entity may be referred to as a "country", such as the West Country in England, "big sky country" (used in various contexts of the American We ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth's Atmosphere
The atmosphere of Earth is composed of a layer of gas mixture that surrounds the Earth's planetary surface (both lands and oceans), known collectively as air, with variable quantities of suspended aerosols and particulates (which create weather features such as clouds and hazes), all retained by Earth's gravity. The atmosphere serves as a protective buffer between the Earth's surface and outer space, shields the surface from most meteoroids and ultraviolet solar radiation, keeps it warm and reduces diurnal temperature variation (temperature extremes between day and night) through heat retention (greenhouse effect), redistributes heat and moisture among different regions via air currents, and provides the chemical and climate conditions allowing life to exist and evolve on Earth. By mole fraction (i.e., by quantity of molecules), dry air contains 78.08% nitrogen, 20.95% oxygen, 0.93% argon, 0.04% carbon dioxide, and small amounts of other trace gases (see Composition below ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Camp David
Camp David is a country retreat for the president of the United States. It lies in the wooded hills of Catoctin Mountain Park, in Frederick County, Maryland, near the towns of Thurmont, Maryland, Thurmont and Emmitsburg, Maryland, Emmitsburg, about north-northwest of the national capital city, Washington, D.C.Frequently Asked Questions . Catoctin Mountain Park, Retrieved on February 4, 2011. "10. Where is Camp David? The Presidential Retreat is within the park however, it is not open to the public and its location is not shown on our park maps for both security and privacy. If you're interested in historical information, visit our Presidential Retreat webpage." It is code-named Naval Support Facility Thurmont. Technically a military installation, it is staffed primarily by the Seabees, the Civil Engineer Corps (CEC), the United Stat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Federal Register
The ''Federal Register'' (FR or sometimes Fed. Reg.) is the government gazette, official journal of the federal government of the United States that contains government agency rules, proposed rules, and public notices. It is published every weekday, except on Federal holidays in the United States, federal holidays. The final rules promulgated by a federal agency and published in the ''Federal Register'' are ultimately reorganized by topic or subject matter and Codification (law), codified in the ''Code of Federal Regulations'' (CFR), which is updated quarterly. The ''Federal Register'' is compiled by the Office of the Federal Register (within the National Archives and Records Administration) and is printed by the United States Government Publishing Office, Government Publishing Office. There are no copyright restrictions on the ''Federal Register''; as a Copyright status of work by the U.S. government, work of the U.S. government, it is in the public domain. Contents The ''Fede ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nautical Mile
A nautical mile is a unit of length used in air, marine, and space navigation, and for the definition of territorial waters. Historically, it was defined as the meridian arc length corresponding to one minute ( of a degree) of latitude at the equator, so that Earth's polar circumference is very near to 21,600 nautical miles (that is 60 minutes × 360 degrees). Today the international nautical mile is defined as exactly . The derived unit of speed is the knot, one nautical mile per hour. Unit symbol There is no single internationally agreed symbol, with several symbols in use. * NM is used by the International Civil Aviation Organization. * nmi is used by the Institute of Electrical and Electronics Engineers and the United States Government Publishing Office. * M is used as the abbreviation for the nautical mile by the International Hydrographic Organization. * nm is a non-standard abbreviation used in many maritime applications and texts, including U.S. Government Coa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flight Level
In aviation, a flight level (FL) is an aircraft's altitude as determined by a pressure altimeter using the International Standard Atmosphere. It is expressed in hundreds of feet or metres. The altimeter setting used is the ISA sea level pressure of 1013 hPa or 29.92 inHg. The actual surface pressure will vary from this at different locations and times. Therefore, by using a standard pressure setting, every aircraft has the same altimeter setting, and vertical clearance can be maintained during cruise flight. Background Flight levels are used to ensure safe vertical separation between aircraft. Historically, altitude has been measured using an altimeter, essentially a calibrated barometer. An altimeter measures ambient air pressure, which decreases with increasing altitude following the barometric formula. It displays the corresponding altitude. If aircraft altimeters were not calibrated consistently, then two aircraft could be flying at the same altitude even thou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mean Sea Level
A mean is a quantity representing the "center" of a collection of numbers and is intermediate to the extreme values of the set of numbers. There are several kinds of means (or "measures of central tendency") in mathematics, especially in statistics. Each attempts to summarize or typify a given group of data, illustrating the magnitude and sign of the data set. Which of these measures is most illuminating depends on what is being measured, and on context and purpose. The ''arithmetic mean'', also known as "arithmetic average", is the sum of the values divided by the number of values. The arithmetic mean of a set of numbers ''x''1, ''x''2, ..., x''n'' is typically denoted using an overhead bar, \bar. If the numbers are from observing a sample of a larger group, the arithmetic mean is termed the '' sample mean'' (\bar) to distinguish it from the group mean (or expected value) of the underlying distribution, denoted \mu or \mu_x. Outside probability and statistics, a wide rang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Airspace Classes (United States)
Airspace class is a category used to divide the sky into different zones, defined by both geographical boundaries and altitude levels. The International Civil Aviation Organization (ICAO) provides standardized airspace classifications that most countries follow. The classification dictates the level of control and services provided to aircraft operating within that airspace. However, nations may choose to implement only certain classes and modify the associated regulations and requirements to suit their needs. Additionally, countries can establish special use airspace (SUA) zones with supplementary regulations to address national security concerns or safety considerations. Abbreviations used in this article ICAO definitions On March 12, 1990, ICAO adopted the current airspace classification scheme. The classes are fundamentally defined in terms of flight rules and interactions between aircraft and air traffic control (ATC). Generally speaking, the ICAO airspaces allocate the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Visual Flight Rules
In aviation, visual flight rules (VFR) is a set of regulations under which a pilot operates an aircraft in weather conditions generally clear enough to allow the pilot to see where the aircraft is going. Specifically, the weather must be better than basic VFR weather minima, i.e., in visual meteorological conditions (VMC), as specified in the rules of the relevant aviation authority. The pilot must be able to operate the aircraft with visual reference to the ground, and by visually avoiding obstructions and other aircraft. If the weather is less than VMC, pilots are required to use instrument flight rules, and operation of the aircraft will be primarily through referencing the instruments rather than visual reference. In a control zone, a VFR flight may obtain a clearance from air traffic control to operate as Special VFR. Requirements VFR requires a pilot to be able to see outside the cockpit to control the aircraft's altitude, navigate, and avoid obstacles and other aircra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Traffic Control
Air traffic control (ATC) is a service provided by ground-based air traffic controllers who direct aircraft on the ground and through a given section of controlled airspace, and can provide advisory services to aircraft in non-controlled airspace. The primary purpose of ATC is to prevent collisions, organise and expedite the flow of traffic in the air, and provide information and other support for pilots. Personnel of air traffic control monitor aircraft location in their assigned airspace by radar and communicate with the pilots by radio. To prevent collisions, ATC enforces Separation (air traffic control), traffic separation rules, which ensure each aircraft maintains a minimum amount of 'empty space' around it at all times. It is also common for ATC to provide services to all General aviation, private, Military aviation, military, and commercial aircraft operating within its airspace; not just civilian aircraft. Depending on the type of flight and the class of airspace, AT ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Controlled Airspace
Controlled airspace is airspace of defined dimensions within which air traffic control (ATC) services are provided. The level of control varies with different airspace class, classes of airspace. Controlled airspace usually imposes higher weather minimums than are applicable in uncontrolled airspace. It is the opposite of uncontrolled airspace. Controlled airspace is established mainly for three different reasons: * high-volume air traffic areas, e.g. near airports * Instrument flight rules traffic under ATC guidance * security, e.g. within an air defense identification zone Controlled airspace usually exists in the immediate vicinity of busier airports, where aircraft used in commercial air transport flights are climbing out from or making an approach to the airport, or at higher Above Ground Level, levels where air transport flights would tend to cruise. Some countries also provide controlled airspace almost generally, however in most countries it is common to provide uncon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Commerce Act Of 1926
The Air Commerce Act of 1926 created an Aeronautic Branch of the United States Department of Commerce. Its functions included testing and licensing of pilots, certification of aircraft and investigation of accidents. In 1934, the Aeronautics Branch was renamed the Bureau of Air Commerce, to reflect the growing importance of commercial flying. It was subsequently divided into two authorities: the Civil Aeronautics Administration (United States), Civil Aeronautics Administration (CAA), concerned with air traffic control, and the Civil Aeronautics Board (CAB), concerned with safety regulations and accident investigation. Under the Federal Aviation Act of 1958, the CAA's powers were transferred to a new independent body, the Federal Aviation Administration (FAA). In the same year, the NASA, National Aeronautics and Space Administration (NASA) was created after the Soviet Union’s launch of the first artificial satellite. The accident investigation powers of the CAB were transferred to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
