17.1 Communication failure (ICAO)
If all attempts to establish contact fail, transmit message twice on
designated channel, proceeded by the phrase “Transmitting
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
If in imc or unlikely to be able to maintain vmc:
17.2 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 220.127.116.11 ]