13-2-4. CONTROLLER PILOT DATA LINK COMMUNICATIONS (CPDLC)
Means of communication.
When CPDLC is available and CPDLC connected aircraft are operating outside of VHF coverage, CPDLC must be used as the primary means of communication.
Voice communications may be utilized for CPDLC aircraft when it will provide an operational advantage and/or when workload or equipment capabilities demand.
When CPDLC is being utilized, a voice backup must exist (e.g., HF, SATCOM, Third party).
When a pilot communicates via CPDLC, the response should be via CPDLC.
To the extent possible, the CPDLC message set should be used in lieu of free text messages.
NOTE: The use of the CPDLC message set ensures the proper “closure” of CPDLC exchanges.
Transfer of Communications to the Next Facility.
When the receiving facility is capable of CPDLC communications, the data link transfer is automatic and is accomplished within facility adapted parameters.
When a receiving facility is not CPDLC capable, the transfer of communications must be made in accordance with local directives and Letters of Agreement (LOAs).
If any portion of the automated transfer fails, the controller should attempt to initiate the transfer manually. If unable to complete the data link transfer, the controller should advise the pilot to log on to the next facility and send an End Service (EOS) message.
If CPDLC fails, voice communications must be utilized until CPDLC connections can be reestablished.
If the CPDLC connection is lost on a specific aircraft, the controller should send a connection request message (CR1) or advise the pilot via backup communications to log on again.
If CPDLC service is to be canceled, the controller must advise the pilot as early as possible to facilitate a smooth transition to voice communications. Workload permitting, the controller should also advise the pilot of the reason for the termination of data link.
When there is uncertainty that a clearance was delivered to an aircraft via CPDLC, the controller must continue to protect the airspace associated with the clearance until an appropriate operational response is received from the flight crew. If an expected operational response to a clearance is not received, the controller will initiate appropriate action to ensure that the clearance was received by the flight crew. On initial voice contact with aircraft preface the message with the following: