EASA SIB 2014-14: Controller Pilot Data Link Communications over Very High Frequency Data Link Mode 2 (CPDLC over VDL Mode 2)

What to do

Operators should update their operational procedures and training to include reversion to voice communication during CPDLC over VDL Mode 2 interruptions and delay reconnection until the next planned session, often the next flight. They should base these procedures on the ICAO GOLD 2nd Edition dated 26 April 2013. All occurrences of CPDLC session interruptions must be reported through established occurrence reporting channels. No specific compliance deadline is stated.

Summary

EASA Safety Information Bulletin SIB No. 2014-14 addresses Controller Pilot Data Link Communications over Very High Frequency Data Link Mode 2 (CPDLC over VDL Mode 2) applicable to all aircraft operators equipped with this system in European airspace. The bulletin highlights issues with frequent interruptions, known as provider aborts, in CPDLC sessions since the service began in some European Flight Information Regions in early 2013. It provides guidance on operational procedures and reporting to mitigate these interruptions and ensure safe communication.

What changed

EASA SIB No. 2014-14 introduces awareness of the higher-than-expected frequency of CPDLC over VDL Mode 2 session interruptions and recommends operational procedures to manage these provider aborts. It emphasizes reverting to voice communications during interruptions and advises reconnection only at the next planned session. The bulletin also directs operators to follow ICAO GOLD guidance for CPDLC VDL Mode 2 operations.

Why it matters

This bulletin is important for aviation professionals because frequent CPDLC session interruptions can increase aircrew workload and contribute to VDL Mode 2 signal congestion, potentially affecting communication reliability and flight safety. Operators and flight crews need to understand and implement recommended procedures to maintain effective communication and reduce operational disruptions. Proper reporting of occurrences supports ongoing investigation and improvement of CPDLC services.