Civil Airspace Overlays

Summary: A guide to the civil airspace layers on the map and what each abbreviation means.

The Civil Airspace section shows UK civil airspace, grouped by altitude band so overlapping airspace at different heights doesn’t clutter the map. Each overlay is colour-coded, and clicking any polygon shows a tooltip explaining what it is.

Boundaries

• FIR (Flight Information Region) / Oceanic — the top-level regions UK airspace is divided into for air traffic services.

ACC Sectors

• London / Scottish, High / Medium / Low, plus Western Radar — the en-route air traffic control sectors, split by area and altitude band.

Surface-Level Airspace

• ATZ (Aerodrome Traffic Zone) — protected airspace around an airfield.
• MATZ (Military Aerodrome Traffic Zone) — the military equivalent.
• CTR (Control Zone) — controlled airspace around a busier airport, usually surface to a set altitude.
• LARS (Lower Airspace Radar Service) — a radar advisory service available to aircraft flying outside controlled airspace.
• CTA (Control Area) — controlled airspace that doesn’t extend to the surface.
• Recreational Zones and UAS Zones — areas with specific rules for recreational flying or drones.

Low-Level Airspace

• TMA (Terminal Manoeuvring Area) — controlled airspace around a busy airport or group of airports, above the surface CTRs.
• CTA — as above, at low level.

Upper Airspace

• UIR (Upper Information Region) — the upper-level equivalent of an FIR.
• FRA (Free Route Airspace) — airspace where aircraft can plan direct routes rather than following fixed airways.
• CTA — as above, at upper level.

Each overlay can be switched on or off independently, so you can build up exactly the picture of controlled airspace you want to see.

Reading an airspace popup

Click any area and the popup opens with a sentence saying what that kind of airspace is, then its class with what that means for a flight, the vertical limits in words (From the surface to 22,000 ft above sea level), the hours (the AIP writes hours as winter time with summer time in brackets; the popup says so), and for danger and restricted areas the activity, the service, the contact and the authority with the shorthand spelt out. Each frequency in a popup says what the service does and which band it sits in.