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Chapter 16. Communications

Table of Contents

16.1. Communication failure (ICAO)
16.2. Communication failure (UK airspace)

16.1. Communication failure (ICAO)

If all attempts to establish contact fail, transmit message twice on designated channel, proceeded by the phrase “Transmitting Blind.”

Set Mode A Transponder Code to 7600.

If in VMC, continue in VMC to the nearest suitable airfield and land, reporting arrival to appropriate ATS by the most expeditious means.

If in IMC or unlikely to be able to maintain VMC:

  • If in airspace where a procedural separation service is being applied, maintain speed and level, or minimum flight altitude if higher, for a period of 20 minutes following failure to report over a compulsory reporting point, then adjust level and speed in accordance with flight plan.

  • If in airspace where an ATS surveillance system is in use, maintain speed and level, or minimum flight altitude if higher, for 7 minutes after Code 7600 is set, then adjust level and speed in accordance with flight plan.

  • If being radar vectored or having been directed to proceed offset using RNAV without specified limit, rejoin the flight plan route no later than the next significant point.

  • On reaching the appropriate NAVAID or fix serving the destination aerodrome, hold if necessary, then at EAT, or if no EAT has been received and acknowledged, computed flight plan ETA, commence an appropriate instrument approach procedure. If possible land within 30 minutes of this time.

  • Watch for visual signals from the tower:

    • Red Pyro: Permission to land cancelled

    • Flashing Red Light: Land elsewhere

    • Continuous Red: Give way to other aircraft, continue circling

    • Flashing Green: Return to circuit, await landing clearance

    • Continuous Green: Permission to land

16.2. Communication failure (UK airspace)

The UK procedures expand on the ICAO procedures:

  • If following a SID fly the published lateral and vertical profiles, including any step climb, until the last waypoint of the procedure is reached. Maintain current speed and last assigned level (or minimum flight altitude if this is higher) until 7 minutes have elapsed since setting 7600. Then adjust speed and level in accordance with current flight plan. This procedure also applies to RNP-1 (PRNAV) departures.

  • If following a STAR, follow the lateral profile but maintain current speed and last assigned level (or minimum flight altitude if this is higher) until 7 minutes have elapsed since setting 7600. Subsequently, arrange descent to be as close as possible to published planning profile. If no profile is published, arrange to be at the IAF at minimum published level. This procedure also applies to RNP-1 (PRNAV) arrivals.

  • If under radar vectors from Approach Control Radar, comply with instructions on radar vectoring chart. If under radar vectors without specified limit from other ATS unit, continue in accordance with last instructions until 3 minutes have elapsed since setting 7600, then proceed in most direct manner to rejoin current flight plan route. If necessary, climb to minimum flight altitude.

  • If performing an SRA, continue visually or by using an alternate approach aid. If this is not possible, carry out a missed approach and continue to the holding position of a suitable aerodrome with a notified instrument approach and carry out that procedure.

[ICAO Annex 10, ICAO DOC 4444, UKAIP ENR 1.1.3.4]