Network Status
Datalink implementation
The map below depicts the implementation of the different datalink technologies per European centre:
- Bulleted list item ATN Baseline 1 enables structured air/ground data communications using ICAO-standard protocols over VDL Mode 2 or L-Band SATCOM in continental airspace for CM, CPDLC and ADS-C services.
- Bulleted list item ATS Baseline 2 enhances ATN B1 with additional services and performance improvements, supporting time-critical operations such as trajectory-based clearances in high-density, high-complexity airspace.
- Bulleted list item FANS 1/A is a legacy datalink system using ACARS over SATCOM and HF/VHF to provide CPDLC and ADS-C services mainly in oceanic and remote airspace. It is noted that the use of ATN is recommended over FANS in the European airspace in line with the regulation.
Per EU Regulation (EU) No 2023/1770, the use of air-ground datalink services is mandatory for aircraft operating above Flight Level (FL285) within European airspace, unless exempted. Some European centers provide datalink services starting at lower FL.
Logon implementation
For the ATN datalink, the aircraft needs to initiate the datalink connection by connecting to the appropriate ground ATS centre (ATSU). Each ATSU implementing datalink is assigned a unique logon code matching the ICAO 4-letter code of the Flight Information Region (FIR). These codes, also called Ground Facility Designators, are specified and maintained in the ICAO EUR Doc 028 (EUR NSAP Address Registry) document.
The following logon codes are currently active:
| Logon code | Facility name | Logon code | Facility name | Logon code | Facility name |
|---|---|---|---|---|---|
| EDUU | RHEIN RADAR | GCCC | ATC UNIT CANARIAS | LIMM | MILANO |
| EDYY | MAASTRICHT | LBSR | SOFIA | LIPP | PADOVA |
| EFIN | HELSINKI | LCCC | NICOSIA | LIRR | ROMA |
| EETT | TALLINN | LDZO | ZAGREB | LJLA | LJUBLJANA |
| EGPX | SCOTTISH | LECB | ATC UNIT BARCELONA | LKAA | PRAHA |
| EGTT | LONDON | LECM | ATC UNIT MADRID | LMMM | MALTA |
| EISN | SHANNON | LFBB | BORDEAUX | LOVV | WIEN |
| EKDK | COPENHAGEN | LFEE | REIMS | LPPC | LISBOA |
| EPWW | WARSZAWA | LFFF | PARIS | LRBB | BUCURESTI |
| ESMM | SWEDEN | LFMM | MARSEILLE | LSAG | GENEVA |
| ESOS | SWEDEN | LFRR | BREST | LSAZ | ZURICH |
| EVRR | RIGA ACC | LHCC | BUDAPEST | LYBA | BEOGRAD |
| EYVC | VILNIUS ACC | LIBB | BRINDISI | LZBB | BRATISLAVA |
Datalink logon requirements are specified in each country’s AIP (Aeronautical Information Publication) under the relevant FIRs. Some ATSUs mandate equipped aircraft to log on to datalink.
The Logon list is a performance-based access system used by several European ANSPs to restrict datalink connectivity to aircraft with proven, reliable ATN avionics, aiming to reduce operational disruptions caused by poorly performing systems. Operators must register their aircraft with up-to-date avionics data to be eligible to log on these centers.
LOF/NAN (Logon Forwarding / Next Applicable Notification) is an OLDI specification mechanism that allows the transferring ATSU to forward a logon request to the downstream ATSU along the flight-s route, reducing pilot workload and ensuring a seamless transition of datalink services between ATSUs that support this function.
COF/MAS (Change Of Frequency/Manual Assumption of communications) is an OLDI specification mechanism that allows the transferring and receiving ATSU to coordinate establishment of radio communication with the receiving ATSU. Implementation of COF/MAS is highly recommended between pairs of ATSUs providing datalink, in order to avoid incidents where ATCOs send CPDLC messages to aircraft not yet assumed.
VDL Mode 2 radio coverage
VDL Mode 2 is the primary air-ground communication technology for ATN datalink services in continental airspace, increasingly being complemented by L-band SATCOM (IRIS service).
The currently available VDL Mode 2 radio frequencies are:
| Fréquence | Désignation |
|---|---|
| 136.675 MHz | Collins Alternate #3 (R) |
| 136.725 MHz | Collins Alternate #1 (W) |
| 136.775 MHz | SITA Alternate #2 |
| 136.825 MHz | Collins Alternate #2 (T) |
| 136.850 MHz | Collins Alternate #4 |
| 136.875 MHz | SITA Alternate #1 |
| 136.900 MHz | SITA Alternate #3 |
| 136.975 MHz | Common Signalling Channel (CSC) |
Collins Alternate #3 (R)
Collins Alternate #1 (W)
Collins Alternate #2 (T)
Common Signalling Channel (CSC)
FANS Accommodation
In addition to ATN/VDL2 datalink, 5 European centres (EGTT, EGPX, EISN, GCCC and LRBB) also accommodate FANS datalink. It is noted that the use of ATN is recommended over FANS in the European airspace in line with the regulation mandating the ATN/VDL2 service only.
Information about deployment is also provided in the NM CNS dashboard.