aviation Aviation includes the activities surrounding mechanical flight and the aircraft industry. ''Aircraft'' includes fixed-wing and rotary-wing types, morphable wings, wing-less lifting bodies, as well as lighter-than-air craft such as hot ...

, an intersection is a virtual

navigation Navigation is a field of study that focuses on the process of monitoring and controlling the movement of a craft or vehicle from one place to another.Bowditch, 2003:799. The field of navigation includes four general categories: land navigation, ...

al fix that helps

aircraft An aircraft is a vehicle that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engine ...

maintain their

flight plan Flight plans are documents filed by a pilot or flight dispatcher with the local Air Navigation Service Provider (e.g. the FAA in the United States) prior to departure which indicate the plane's planned route or flight path. Flight plan format ...

. It is usually defined as the

intersection In mathematics, the intersection of two or more objects is another object consisting of everything that is contained in all of the objects simultaneously. For example, in Euclidean geometry, when two lines in a plane are not parallel, their ...

(in the

geometrical Geometry (; ) is, with arithmetic, one of the oldest branches of mathematics. It is concerned with properties of space such as the distance, shape, size, and relative position of figures. A mathematician who works in the field of geometry is ca ...

sense) of two VOR radials. They are usually identified as major airway intersections where aircraft, operating under

instrument flight rules In aviation, instrument flight rules (IFR) is one of two sets of regulations governing all aspects of civil aviation aircraft operations; the other is visual flight rules (VFR). The U.S. Federal Aviation Administration's (FAA) ''Instrument Fl ...

, often change direction of

flight Flight or flying is the process by which an object moves through a space without contacting any planetary surface, either within an atmosphere (i.e. air flight or aviation) or through the vacuum of outer space (i.e. spaceflight). This can ...

while en route. According to the

Federal Aviation Regulations The Federal Aviation Regulations (FARs) are rules prescribed by the Federal Aviation Administration (FAA) governing all aviation activities in the United States. The FARs comprise Title 14 of the Code of Federal Regulations (CFR). A wide variety o ...

, some intersections are designated as mandatory reporting points for pilots who are not in radar contact with

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 airs ...

. Intersections also play an important role in departure and approach procedures. All intersections have an

alphabet An alphabet is a standardized set of basic written graphemes (called letters) that represent the phonemes of certain spoken languages. Not all writing systems represent language in this way; in a syllabary, each character represents a sy ...

ical or

alphanumeric Alphanumericals or alphanumeric characters are a combination of alphabetical and numerical characters. More specifically, they are the collection of Latin letters and Arabic digits. An alphanumeric code is an identifier made of alphanumeric ...

designation. Near major

airport An airport is an aerodrome with extended facilities, mostly for commercial air transport. Airports usually consists of a landing area, which comprises an aerially accessible open space including at least one operationally active surfac ...

s, the intersection designation code typically consists of three letters followed by the

runway According to the International Civil Aviation Organization (ICAO), a runway is a "defined rectangular area on a land aerodrome prepared for the landing and takeoff of aircraft". Runways may be a man-made surface (often asphalt, concrete, ...

number. Most other intersection designations consist of five-letter combinations that are either pronounceable or chosen for their

mnemonic A mnemonic ( ) device, or memory device, is any learning technique that aids information retention or retrieval (remembering) in the human memory for better understanding. Mnemonics make use of elaborative encoding, retrieval cues, and imager ...

value, since either

or the flight plan may require the

pilot An aircraft pilot or aviator is a person who controls the flight of an aircraft by operating its directional flight controls. Some other aircrew members, such as navigators or flight engineers, are also considered aviators, because they ar ...

to announce the designation. In the terminal procedure or approach plate example to the right, note that two of the intersections are called DONUT and KOFFE. Many intersections are named because of local points of interest. In the case of Carroll County Airport, there is a popular diner located on the field to which many pilots fly.

References

''Instrument Procedures Handbook''
Federal Aviation Administration, 2007. FAA-H-8261-1A. Retrieved 2010-12-04. Air navigation {{Aviation-stub

See also

References