Control zone - Wikipedia

In aviation, a control zone (CTR) is a volume of controlled airspace, usually situated below a control area, 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 them after receiving a specific clearance from air traffic control. This means that air traffic control 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In the USA the term control zone is no longer used^[1] and has been replaced by airspace class D. Typically it extends 5 miles in diameter with a height of 2500 ft AGL (above ground level) around small commercial airports. Aircraft are required to establish radio contact^[2] 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 and usually extend from the surface to 2000 ft 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 is a minimum required cloud ceiling of 1500 ft AGL.^[3]

References

[edit]

^ FAA: [1]
^ FAA: [2]
^ Deutsche Flugsicherung: Airspace Structure/Visual Flight Rules in the Federal Republic of Germany – Example Archived 2018-12-24 at the Wayback Machine

v t e Commercial aviation
Airlines	Airline codes Airline holding companies Cargo airline Charter airlines Flag carriers Low-cost airlines Non-scheduled airline Passenger airlines Regional airlines
Alliances	Oneworld SkyTeam Star Alliance Value Alliance Vanilla Alliance U-FLY Alliance
Trade groups	International ACO ATAG IATA IATAN IFALPA ISTAT United States A4A RAA Europe A4E ASD ECA EBAA ERA ETWF Other regions AACO AAPA AFRAA RAAA
Aircrew	Pilot in command (Captain) First officer Second officer Third officer Relief crew Flight attendant Flight engineer Loadmaster Aircraft pilot Purser Dead mileage
Airliner	Travel class First class Business class Premium economy class Economy class Basic economy class Aircraft cabin Aircraft lavatory Aircraft seat map Airline meal Airline seat Buy on board Crew rest compartment In-flight entertainment Inflight smoking Galley Sickness bag
Airport	Aerodrome Airline hub Airport check-in Airport lounge Airport rail link Airport terminal Airside pass Airstair Boarding Domestic airport Gate International airport Jet bridge Low-cost carrier terminal Runway Transit hotel
Customs / Immigration	Arrival card Border control (internal) Departure card Passport Timatic Travel document Travel visa (Electronic)
Environmental effects	Hypermobility Environmental effects of aviation
Law	Air transport agreement Air route authority between the United States and China Bermuda Agreement (UK–US, 1946–1978) Bermuda II Agreement (UK–US, 1978–2008) Cross-strait charter Beijing Convention Cape Town Treaty Chicago Convention Convention on the Marking of Plastic Explosives European Common Aviation Area Flight permit Freedoms of the air EU–US Open Skies Agreement Hague Hijacking Convention Hague Protocol Montreal Convention Paris Convention of 1919 Rome Convention Sabotage Convention Tokyo Convention Warsaw Convention
Intergovernmental organizations	ICAO ECAC Eurocontrol EASA ENCASIA
Baggage	Bag tag Baggage allowance Baggage carousel Baggage cart Baggage reclaim Baggage handler Baggage handling system Baggage sizer Checked baggage Hand luggage Lost luggage (WorldTracer) Luggage lock
Aviation safety	Air rage Air traffic control Air traffic service Aircraft safety card Airport authority Airport crash tender Airport police Airport security Airspace class Area control center Brace position Civil aviation authority Control area Control zone Controlled airspace Evacuation slide Flight information region Flight information service Flight recorder Instrument flight rules Overwing exits Pre-flight safety demonstration Sky marshal Special use airspace Special visual flight rules Terminal control area Terminal control center Uncontrolled airspace Upper information region Visual flight rules
Airline tickets	Airline booking ploys Airline reservations system Airline ticket Airline timetable Bereavement flight Boarding pass Codeshare agreement Continent pass Electronic ticket Fare basis code Flight cancellation and delay Frequent-flyer program Government contract flight One-way travel Open-jaw ticket Overbooking (Overselling) Passenger name record Red-eye flight Round-the-world ticket Standby Tracking Travel agency Travel website
Ground crew	Aircraft maintenance technician Aircraft ground handling Baggage handler Flight dispatcher
Miscellaneous	Air cargo Air travel Aviation taxation and subsidies Mile high club

See also

References