Aeronautical radio is divided into two main functions – aircraft and ground stations (including both voice and radionavigation).
Ofcom issues licences to authorise these uses of radio.
Aircraft radio licences
The aircraft radio licence is available in two forms:
This licence covers the aircraft for all aeronautical radio equipment it carries. The licence fee is linked to the maximum take-off weight of the aircraft.
This licence covers the use of one handheld portable VHF radio, which is not tied to a single aircraft. It has a flat fee. The equipment is not for use on the ground, other than as part of an aircraft station.
This licence provides the spectrum authorisation to use variety of radio equipment on a drone. The licence covers equipment for command and control, including mobile and satellite terminals, as well as other safety systems. This will allow UAS operators to have access to a range of technologies that could enable them to operate a wider range of services and over longer distances.
Most drones use spectrum designated for Wi-Fi or model aircraft. Drones that only use this equipment do not need to obtain a licence as they are already exempted from the need to obtain a licence under our regulations.
Aircraft equipment types
The aircraft radio licence lists and permits the main equipment types that are used on aircraft. These are selectable in the application form. Please see below for a brief description of each type:
Satellite-facing terminals and complimentary ground component-facing terminals forming part of a 2 GHz mobile satellite service.
The following equipment type is not listed on the aircraft application form but can be requested by writing to Ofcom and is only for genuine search and rescue aircraft with the approval of the Maritime and Coastal Agency.
Air Traffic Control Transponder - Used on aircraft to automatically respond to ground-based ATC secondary surveillance radar interrogations. It provides altitude information, and surveillance data to aid in the tracking of aircraft by air traffic controllers. Surveillance data is also used by the airborne collision avoidance system (ACAS) to identify threat aircraft and co-ordinate evasive manoeuvres.
Airborne radar operating between 13250 to 13400 MHz.
Area Navigation (AKA: RNAV) - Navigation from point to point. The system will receive sensor inputs and compute the best track between points.
Automatic Direction Finder - Determines the relative bearing from the aircraft to a ground-based transmitter.
Distance Measuring Equipment - Used to determine the distance from a VORTAC, VORDME or localizer ground station. Accurate to within half a mile or three percent, aircraft distance to the station is typically displayed to the pilot and can be used in conjunction with other DME distances or other navigation data to determine aircraft position in RNAV systems.
When operating in the emergency frequency (121.5 MHz) the equipment may operate on 25 kHz channel spacing.
When operating on the auxiliary frequency for search and rescue operations (123.1 MHz) or the airport fire service frequency (121.6 MHz), the equipment may operate 25 kHz channel spacing.
The dedicated radio device used by public safety bodies for voice and data communications over the Emergency Services Network (ESN). Use of these frequency bands requires authorisation from HM Home Office.
Sending and receiving Earth Station(s) on Mobile Platforms (“ESOMPs”) on board an aircraft for the purpose of providing wireless telegraphy links between the ESOMP and Satellite(s).
Global Positioning System - Uses radio signals transmitted by satellites to determine accurate aircraft location.
High Frequency Communication - Radio transmissions at frequencies between 2 and 30 MHz are widely used for long distance communications.
Installing and operating maritime and other radio apparatus. Addition of MMSI station identifier. Use of these frequency bands and allocation of MMSI station identifier requires authorisation from the Maritime and Coastguard Agency (MCA).
By means of a transmitter, marker beacons serve to identify a particular location in the space along an airway or on the approach to an instrument runway.
Establishment, installation and use of the radio equipment for the purposes of mobile communication services on board aircraft.
The Obstacle Detection Radar is a viable solution that can detect both moving and stationary objects in its field of view, providing range and bearing information for collision avoidance.
Indicates the aircraft's height over water or terrain by means of radio signal.
Equipment that provides telephone and data link solutions to aircraft via a communications satellite.
Traffic Alert and Collision Avoidance System/ Airborne Collision Avoidance System - Determines the relative altitude and proximity of surrounding aircraft and provides warning if the risk of mid-air collision is present. ACAS can issue advisories to the crew so that they may instigate evasive manoeuvres.
UHF radio equipment operating between 453.0125 to 462.4875 MHz.
Very High Frequency Communication and Navigation – Equipment installed onto aircraft for these purposes.
Very High Frequency Navigation - Capable of receiving and processing ILS Localizer, Glideslope, Marker Beacon and VOR (VHF Omni-directional radio) signals.
Portable VHF radios for use in aircraft.
Wireless access system on the standard 2 GHz and 5 GHz WiFi bands and Ku Satellite band on board the aircraft.
Equipment capable of detecting precipitation via the reflection of microwaves.
Aeronautical ground station licences
These licences authorise the installation and use of a radio installations which provide ground to air communication.
We do not normally issue a ground station licence, until we are satisfied that the ground station has been assessed as fit for purpose by the CAA.
Licences normally cover a single site. A separate fee is payable for each assigned working frequency.
There are several types of ground station radio licences to cover the main types of ground to air service. These are as follows:
| Service types | Description |
|---|---|
Microlight Balloon Glider Parachute Hang/Para Glider | Common air to ground frequencies which have been assigned to general aviation operations and sporting use such as the common glider frequency. |
| Service types | Description |
|---|---|
Air/Ground | A two-way communication between an aircraft and a ground station in which the ground operator may only pass advisory information regarding the situation local to the aerodrome. |
AFIS Aerodrome Flight Information Service | A two-way communication between an aircraft and a ground station, in which the ground operator may only pass advisory information regarding the airborne situation local to the aerodrome but can pass instructions to aircraft on the ground at the aerodrome. |
TWR Aerodrome Control Service | Tower (TWR) - A two way communication between an aircraft and a ground station, in which the ground operator controls the aircraft in the vicinity of an aerodrome traffic zone when the aircraft is flying with visual reference to the aerodrome. |
| Service types | Description |
|---|---|
APP Approach Control Service | A two way communication between an aircraft and a ground station, in which the ground operator controls the aircraft in the vicinity of an aerodrome traffic zone when the aircraft is not flying by visual reference to the aerodrome. |
| Service types | Description |
|---|---|
ACC Area Control Centre Service | A two way communication between an aircraft and a ground station, in which the ground operator provides control instructions to the aircraft within a defined geographical region or sector. |
FIS Flight Information Service | Flight Information Service (FIS) - A two way communication between an aircraft and a ground station, in which the ground operator may only pass advisory information as requested by the pilot. This information may include situation awareness and weather information. |
| Service types | Description |
|---|---|
VOLMET | A broadcast transmission from a ground station to one or more aircraft in which meteorological information relating to a number of aerodromes as defined in the UK AIP. Within the UK this service is regarded as an air traffic control service. |
ATIS Arrival Automatic Terminal Information Service | Automatic Terminal Information Service (ATIS) - A broadcast transmission from a ground station to one or more aircraft in which information relating to the aerodrome from which the transmission is being made is conveyed. Within the UK this service is regarded as an air traffic control service and may only be provided by an aerodrome which also provides a tower and/or an approach service. |
| Service types | Description |
|---|---|
ACARS Aircraft Communications Addressing and Reporting System | Slow speed data communication known for operational control. |
| Service types | Description |
|---|---|
VDL VHF Air-Ground Digital Link | Very High Frequency Data Link. |
| Service types | Description |
|---|---|
OPC Operational Control | A two way communication between an aircraft and a ground station for the purposes stated below: "Operational Control. The exercise of authority over the initiation, continuation, diversion or termination of a flight in the interest of safety of the aircraft and the regularity and efficiency of the flight." Currently OPC services are either provided by voice communications or a slow speed data communication known as ACARS. Operations Control licences can only be issued to radio stations set up to communicate with company aircraft, or aircraft for which the licensee is the operating agency. |
| Service types | Description |
|---|---|
AS Aerodrome Surface | Either a two way communication between an aircraft and a ground station, in which the ground operator provides either control to or information for an aircraft on the ground. |
GMC Ground Movement Control DATIS Departure ATIS | This category includes Ground movement Control (GMC) & Fire. An automated broadcast service passing aerodrome information from a ground station to an aircraft on the ground at that aerodrome. This category covers departure ATIS (DATIS). |
| Service types | Description |
|---|---|
EMERG | Emergency Frequency - 121.5 MHz Auxiliary Frequency Search & Rescue (SAR) 123.1 MHz Aerodrome Fire Vehicle 121.6 MHz |
| Service types | Description |
|---|---|
Aeronautical Ground Station: HF | Aeronautical ground stations where an HF assignment is required. |
| Service types | Description |
|---|---|
Offshore Fixed/Mobile Installations and Vessels – Traffic/Logistics (A/G) {Can also cover mobiles} | Offshore platforms operating in UK territorial waters that are assigned a Traffic Frequency (A/G) and/or a Logistics Frequency (OPC), or, a single frequency to be used for both traffic and logistic services. The licence also covers mobile platforms where the Radio Frequency allocation is carried out using an area system based on block on sub blocks. Details of this are published in the UK AIP (CAP 32). |
This licence authorises the installation and use of aeronautical navigation aids.
The licence fee is charged by the number of frequencies used by each individual navigation aid at a declared location.
The main types of navigation aid covered by the licence are as follows:
- The Non-directional radio Beacon (NDB) service is used for short and medium range navigation. When used with automatic direction finder (ADF) equipment in aircraft the NDB provides a bearing with moderate accuracy. The NDB is used by larger aircraft over sea or over land routes and is extensively deployed at general aviation aerodromes where it provides a cost effective and easily installed facility.
- The Instrument Landing System (ILS) is one of the International Civil Aviation Organization (ICAO) standard approach and landing systems. The ILS localizer is coupled with glide path frequencies and with Microwave Landing System (MLS) and or Distance Measuring Equipment (DME). MLS is a newer system, which operates in a similar manner to ILS.
- The VHF omnidirectional radio range (VOR) is a short/medium range navigation aid. VOR is normally associated with Distance Measuring Equipment (DME).
- Distance Measuring System (DME) is the ICAO standard system for the determination of ranges within radio line of sight using pulse techniques and time measurement. DME is the standard system used for en route and terminal navigation.
A licence is available to cover Aeronautical Primary radar and Secondary Surveillance Radar (SSR). SSR is an ICAO standard system employing secondary radar principles used either by itself or co-located and synchronized with primary radar. All SSR installations have a frequency for ground-air interrogation and a frequency for the air-ground reply.
Radio equipment
Ground radio equipment designed for 25 kHz channel spacing must be able to operate on any channel between 118.000 MHz and 136.975 MHz in 25 kHz steps. Equipment designed for 8.33 kHz channel spacing must be able to operate on any channel between 118.000 MHz and 136.475 in 8.33 kHz steps. Under EU legislation, most aeronautical ground station radio equipment must operate on 8.33 kHz channel spacing.
Equipment and systems intended for analogue voice and ACARS data link communications must comply with the Minimum Performance Specification published by the CAA.
Frequencies may only be authorised for use within the United Kingdom Flight Information Region, including the UK Continental Shelf.
Use of the equipment
Aeronautical radio messages must be limited to those concerning flight safety or flight regularity. Public correspondence and messages relating to air carrier/company business communications and passenger service/convenience are not permitted.