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Airspace Structures & Restrictions

Understand the main airspace structures and special restrictions for UK drone operators: FRZs, Prohibited Areas, RA(T)s, Danger Areas, Temporary Segregated and Reserved Areas, MATZ, TMZ, RMZ, and Military Low Flying Areas.

Contents

Flight Restriction Zones (FRZ / RPZ)

  • What is it? Statutory protection around aerodromes and heliports that restricts unmanned aircraft without permission.
  • Typical shape and vertical limits:
    • Aerodromes: ATZ cylinder roughly 2 to 2.5 NM to 2,000 ft AAL, plus Runway Protection Zones about 5 km by 1 km to 2,000 ft.
    • Heliports: Typically a 2 NM cylinder to 2,000 ft with no RPZs.
    • Spaceports: Often around 5 km to 2,000 ft AAL.
    • Always check the local AIP for exact geometry.
  • Permissions Needed to Enter: Explicit permission from the aerodrome operator or ATC is required to fly inside the FRZ or RPZ.
  • How to Check: Use Drone Assist, AIP ENR, and local aerodrome information.

Prohibited Areas and Restricted Areas

  • What is it? Airspace permanently protected for safety or security. Common examples include nuclear sites, prisons, and government installations.
  • Permissions Needed to Enter: You must have approval from the controlling authority before flight within the boundary.
  • How to Check: Consult the UK AIP ENR and Drone Assist for current published boundaries and contact details. Activity and vertical limits vary by location and may have set hours or be permanent.

Restricted Area (Temporary) (RA(T))

  • What is it? A temporary restriction that creates a restricted area for a defined period, often for large events, air displays, emergency response, or aerial work.
  • Activation: Typically notified by AIP Supplement and NOTAM. May activate at short notice.
  • Permissions Needed to Enter: Entry requires explicit permission from the controlling authority and compliance with conditions.
  • How to Check: Review the NOTAM and AIP Supplement for coordinates, times, and contact details.

Danger Areas and Temporary Danger Areas (TDA)

  • What is it? Airspace where activities dangerous to flight may take place, such as live firing, explosives, or missile testing.
  • Activation: Permanent, scheduled, or by NOTAM for TDA. Status can change within the day.
  • Permissions Needed to Enter: Do not enter an active Danger Area without explicit clearance from the controlling authority.
  • How to Check: Confirm status and active times via NOTAM, AIP, or the controlling unit.

Temporary Segregated Areas (TSA) and Temporary Reserved Areas (TRA)

  • What is it? Airspace temporarily set aside for exclusive use to segregate specific activities from other traffic. Often used for high-risk UAS trials or military activity. When active, only the authorised users may enter, all other aircraft are excluded.
  • Activation: By schedule or NOTAM. Details are published in AIP Supplements or relevant ENR sections.
  • Permissions Needed to Enter: Your Operational Authorisation must explicitly cover the TSA or TRA or you must be named in the approval.
  • How to Check: Review the AIP ENR, any AIP Supplements, and current NOTAM for activation, boundaries, and conditions.

Military Aerodrome Traffic Zone (MATZ)

  • What is it? A military traffic zone around MOD aerodromes intended to protect military aircraft during take off, approach, and circuit.
  • Typical shape and vertical limits: Usually a 5 NM radius from surface to 3,000 ft AAL, often with stubs from 1,000 to 3,000 ft AAL extending 5 NM from runway ends. Local variations exist.
  • Permissions Needed to Enter: Remains Class G (Uncontrolled) airspace for civil users, however coordination with ATC is strongly recommended.
  • How to Check: AIP aerodrome and ENR entries. Contact the unit or the Low Flying Booking Cell for coordination advice.

Transponder Mandatory Zone (TMZ)

  • What is it? Defined airspace where aircraft must carry and operate a functioning transponder, usually Mode S, to enhance surveillance.
  • Where and when it appears: May overlay Class G or controlled airspace in complex terminal or lower airspace environments.
  • Permissions Needed to Enter: Typical small drones cannot meet transponder requirements. Permission is rarely applicable to Open Category or standard Specific Category operations.
  • How to Check: AIP ENR and aeronautical charts list TMZ boundaries, vertical limits, and associated requirements.

Radio Mandatory Zone (RMZ)

  • What is it? Airspace where aircraft must make and maintain two way radio contact with the controlling ATSU before and during entry.
  • Where and when it appears: Common in busy or complex Class G around aerodromes or routes. Activity may be limited to published hours.
  • Permissions Needed to Enter: UAS generally cannot comply without certified radio equipment and explicit prior coordination or authorisation.
  • How to Check: Review AIP ENR and NOTAM for operating hours, frequencies, and procedures.

Military Low Flying Areas (MLFA)

  • What is it? Designated zones used by military aircraft for low level training, including fast jets, helicopters, and transports, often as low as 250 ft AGL and sometimes to surface.
  • Activation: Can be active without NOTAM. Activity varies by day and route and can include night operations at high speed.
  • Permissions Needed to Enter: Not restricted airspace, but operational coordination is strongly advised due to collision risk.
  • How to Check: Contact the Military Low Flying Booking Cell for free on 0800 515544 for current activity and coordination advice. Cross check with NOTAM and local units if available.