Control zone
Encyclopedia
A control zone is an aviation
term that describes a volume of controlled airspace
, normally around an airport, which extends from the surface to a specified upper limit, established to protect air traffic operating to and from that airport. Because CTRs are, by definition, controlled airspace, aircraft can only fly in it after receiving a specific clearance from air traffic control. This means that ATC at the airport know exactly which aircraft are in that airspace, and can take steps to ensure aircraft are aware of each other, either using separation or by passing traffic information.
In the USA the term control zone is no longer used and has been replaced by airspace class D. Typically it extends 5 miles in diameter with a high of 2500ft AGL (above ground level) around small commercial airports. Aircraft are required to establish radio contact with the control tower before entering and to maintain in contact while in class D airspace. This implies that an aircraft must be equipped with at least a portable radio to fly in Class D airspace.
In the UK, control zones are normally class D airspace (but also class A at Heathrow and Jersey) and usually extend from the surface to 2000ft AGL. They can be observed to be usually rectangular, extending along the axis of the main runway, although irregular shapes may be used where more complex airspace dictates this (see Liverpool and East Midlands). A control area
(CTA) is often placed between a CTR and nearby airways to give uninterrupted controlled airspace to airways arrivals and departures.
In Germany, control zones are a special type of class D airspace, called D (CTR). The main difference to the regular German class D airspace is, that within a CTR there are no minimum-distances for VFR-traffic to keep from clouds (though clouds may not be touched).
Aviation
Aviation is the design, development, production, operation, and use of aircraft, especially heavier-than-air aircraft. Aviation is derived from avis, the Latin word for bird.-History:...
term that describes a volume of controlled airspace
Controlled airspace
Controlled airspace is an aviation term used to describe airspace in which ATChas the authority to control air traffic, the level of which varies with the different classes of airspace. Controlled airspace is established mainly for three different reasons:...
, normally around an airport, which extends from the surface to a specified upper limit, established to protect air traffic operating to and from that airport. Because CTRs are, by definition, controlled airspace, aircraft can only fly in it after receiving a specific clearance from air traffic control. This means that ATC at the airport know exactly which aircraft are in that airspace, and can take steps to ensure aircraft are aware of each other, either using separation or by passing traffic information.
In the USA the term control zone is no longer used and has been replaced by airspace class D. Typically it extends 5 miles in diameter with a high of 2500ft AGL (above ground level) around small commercial airports. Aircraft are required to establish radio contact with the control tower before entering and to maintain in contact while in class D airspace. This implies that an aircraft must be equipped with at least a portable radio to fly in Class D airspace.
In the UK, control zones are normally class D airspace (but also class A at Heathrow and Jersey) and usually extend from the surface to 2000ft AGL. They can be observed to be usually rectangular, extending along the axis of the main runway, although irregular shapes may be used where more complex airspace dictates this (see Liverpool and East Midlands). A control area
Control area
A control area is an aviation term that describes a volume of controlled airspace that exists in the vicinity of an airport. It has a specified lower level and a specified upper level. It usually is situated on top of a control zone and provides protection to aircraft climbing out from the airport...
(CTA) is often placed between a CTR and nearby airways to give uninterrupted controlled airspace to airways arrivals and departures.
In Germany, control zones are a special type of class D airspace, called D (CTR). The main difference to the regular German class D airspace is, that within a CTR there are no minimum-distances for VFR-traffic to keep from clouds (though clouds may not be touched).