An Air/Ground Communication Service (AGCS) provides limited information to pilots at smaller aerodromes. The callsign suffix of these stations is “Radio”. Air/Ground Operators may not issue instructions or clearances to pilots on the ground, and may only pass information to pilots. This information will include weather, traffic and any regional information a pilot may require. All decisions on the ground and in the air remain with the pilot at aerodromes with this level of service.
An Air/Ground Operator must:
Firstly you will need the following information:
Note: AGCS cannot issue squawk codes, IFR/VFR clearances, or give departure instructions to a pilot, this responsibility will be through the next ATS the pilot is in contact with.
When the pilot of an aircraft first makes contact with an AGCS when on the ground, they will often call up requesting a radio check and airfield information. The following information shall be provided:
| Transmitter | Phraseology |
|---|---|
| Pilot | "Caernarfon Radio, G-ERFS request radio check 122.255 and airfield information for a departure flight to Blackpool." |
| AGCS | "G-ERFS, Caernarfon Radio, readability 5, runway 25 right hand circuit, QFE/QNH 1013." |
| Pilot | "Runway 25 right hand QFE/QNH 1013, taxing to holding point charlie runway 25." |
| AGCS | "G-FS, roger." |
| Transmitter | Phraseology |
|---|---|
| Pilot | "G-FS, holding point charlie runway 25, ready for departure" |
| AGCS | "G-FS, roger traffic C42 microlight downwind, surface wind 250, 8 knots." |
| Pilot | "Roger, taking off G-FS ." |
Should no traffic be in the area, the phrase “no reported traffic” will be used.
Note: The phrase “at your discretion” must not be used at any point by an Air/Ground Operator, as this is a phrase associated with AFISO phraseology.
| Transmitter | Phraseology |
|---|---|
| Pilot | "G-FS, departing the circuit to the east, changing to Valley Radar 125.225" |
| AGCS | "G-FS, roger, good-day." |
The procedure for an aircraft joining the circuit is very similar to one calling for taxi, the same information is passed with traffic information this time. Let’s look at an example:
| Transmitter | Phraseology |
|---|---|
| Pilot | "Caernarfon Radio, G-NINC." |
| AGCS | "G-NINC, Caernarfon Radio, pass your message." |
| Pilot | "G-NINC is a PA28 from Sleap, request joining information." |
| AGCS | "G-NC, runway 25 right hand, QFE/QNH 1013 no reported traffic." |
| Pilot | "Runway 25 right hand QFE/QNH 1013, joining overhead G-NC." |
The pilot will then usually perform a standard overhead join, this ensures the pilot has full situational awareness of the circuit he/she is about to enter. This is important as Air/Ground Operators may not issue instructions.
The overhead, descending deadside, crosswind, downwind and base leg calls are acknowledged with “*Callsign* Roger” and any additional traffic information that may prove beneficial to the pilot if applicable.
| Transmitter | Phraseology |
|---|---|
| Pilot | "G-NC Final runway 25 full stop" |
| AGCS | "G-NC, roger, no reported traffic surface wind 260, 10 knots." |
Air/Ground Operators may not issue instructions, including instructing where aircraft may park. This naturally may not be convenient at a busy aerodrome where parking is limited or surfaces may be unsuitable, therefore the following terminology may be used.
| Transmitter | Phraseology |
|---|---|
| Pilot | "G-NC active vacated, request parking information." |
| AGCS | "G-NC, suggest vacate left onto alpha, and stand 6 is available." |
| Pilot | "G-NC taxing to stand 6." |
| AGCS | "G-NC, roger." |
An aircraft transiting the overhead of an Air/Ground aerodrome will usually make a call to let the operator and traffic know his intentions, a pilot may also request weather information from the AGCS. Let’s look at an example of a typical call made by an aircraft transiting the ATZ of an AGCS aerodrome.
| Transmitter | Phraseology |
|---|---|
| Pilot | "Caernarfon Radio, Mallard 208, Jupiter helicopter, 5 miles northeast 1500ft transiting your overhead North to South, request traffic information." |
| AGCS | "Mallard 208, Caernarfon Radio, one Cessna 182 right hand downwind for runway 25, Caernarfon QNH 1020." |
| Pilot | "Visual on the Cessna 182 on downwind, QNH 1020, Mallard 208." |
| Pilot | "Mallard 208 Clear of the ATZ to the south, changing frequency to Valley Radar 125.225 ." |
| AGCS | "Mallard 208, roger, good day." |
Procedures during emergencies are similar for AGCS, AFIS and ATC services and work towards the common cause of assisting the pilot. Let’s look at an example emergency message.
| Transmitter | Phraseology |
|---|---|
| Pilot | "Mayday, Mayday, Mayday. Tatenhill Radio, G-MAYD, Tomahawk, engine failure forced landing runway 08, PPL, 2 POB." |
| AGCS | "G-MAYD, roger mayday, no reported traffic surface wind calm " |
| Pilot | "All stations, Tatenhill Radio, stop transmitting, mayday." |
As you can see, the responsibilities of an AGCS are limited to providing information only to a pilot, the responsibility is with the pilot to ensure safe separation from other traffic is maintained at all times.