Controlled airspace is
airspace of defined dimensions within which
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 air ...
(ATC) services are provided. The level of control varies with different
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
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 ...
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
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 uncontrolled airspace in areas where significant air transport or military activity is not expected.
The
International Civil Aviation Organization
The International Civil Aviation Organization (ICAO ) is a specialized agency of the United Nations that coordinates the principles and techniques of international air navigation, and fosters the planning and development of international sch ...
divides airspace into seven classes, from
A to G, in order of decreasing ATC regulation of flights. Classes A to E are controlled airspace. Flight 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 ...
(IFR) is allowed in all controlled airspace. Some countries also permit IFR in uncontrolled airspace). Flight under
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 tha ...
(VFR) is permitted in all airspace except class A.
See also
*
Airspace class
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 co ...
*
Prohibited airspace
*
Restricted airspace
*
Special use airspace
*
Terminal control area
References
Air traffic control
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