If I use CPDLC via FANS-1/A am I compliant with the DLS IR?
CPDLC via FANS-1/A cannot ensure the performance requirements mandated through the DLS IR, the only system currently capable to achieve this is ATNVDL Mode 2. Additionally, the FANS 1/A versus ATN B1 CPDLC message set may be different (i.e. certain messages not used) within a certain operational context.
Note 1: FANS-1/A are CPDLC capable installation designed in accordance with the relevant interoperability specifications in Eurocae standard ED-100/ED-100A.
Note 2: Aircraft with a first CofA prior to 1 January 2018 and equipped with FANS 1/A data link prior to this date are exempted from compliance.