1.   Introduction

The current crew and radio operator voice communications procedures for initial voice contact with the Aeronautical Stations for flights using CPDLC in the NAT Region are published in the ICAO Doc 10037 GOLD Manual, Appendix B, and are applied without changes in the Santa Maria FIR.

In summary, it is required that “Prior to or upon entering each NAT oceanic CTA, the flight crew should contact the appropriate aeronautical radio station” (B.4.3.1.1.2).

If this procedure fails, the radio operators in Santa Maria RADIO are automatically advised by the ground ATM system when an aircraft is inside the FIR but with no voice contact established. Santa Maria RADIO intends to explore the possibility of implementing a new procedure for flights using CPDLC and entering Santa Maria FIR.For this purpose, following a safety assessment of the change, it was decided to implement a 12-month trial to evaluate if the expected benefits are achieved.

At any time, if the crew chooses to apply the current procedures instead of those proposed for the trial period, the radio operator will respond accordingly.

The proposed change is expected to:

2.   Purpose of the circular

The purpose of this circular is to advise pilots and operators of the planned trial changing the crew and radio operator procedures regarding the initial voice contact with Santa Maria RADIO on HF for flights using CPDLC.

3.   Procedures

3.1 Flight crew – Contact with aeronautical radio station

1) Upon entering Santa Maria FIR, if LPPO is established as CDA and CPDLC communications is operational, the flight crew shall:

1. Not initiate a voice contact on HF and, if applicable, tune the onboard radio(s) according to last information received from the previous Radio Station or in the ACARS FSM message received in reply to an RCL;
2. Wait to receive the Santa Maria RADIO HF frequency assignment via CPDLC (either an uplink to monitor or to contact on HF primary and secondary frequencies);
3. If applicable, update the frequencies, tune the onboard radio(s) accordingly;
4. Expect to receive a SELCAL call from Santa Maria RADIO.

2) 6 minutes after crossing the FIR boundary, if no uplink HF frequency assignment message is received nor a SELCAL call, advise ATC via CPDLC.

3) After receiving the frequency assignment via CPDLC, if the SELCAL is not received within 6 minutes, try to established voice contact (HF/VHF/SATVOICE) or advise ATC via CPDLC.

3.2 Radio operator – Establishment of initial voice contact with flight using CPDLC

1) Upon the system alert regarding a flight inside Santa Maria FIR without voice communications established:

1. Verify the HF frequencies uplinked to the flight;
2. Send the SELCAL on the primary frequency;
3. If no reply from the crew, send the SELCAL on the secondary frequency;
4. If still no reply from the crew, uplink a new message with other frequency assignment considered appropriate and try again to send SELCAL;
5. If no reply from the crew, apply the existing procedures for voice communications failure (e.g., SATVOICE, VHF, other radio station, etc.).

4.   Implementation plan

The trial is planned to start on 16-May-2024.

5.   Points of contact

For further Information, please contact:

Luis Tojais Head of Air Traffic Services, Santa Maria FIR NAV Portugal E.P.E. Phone:+351 296 820 539 Email: [email protected]