ANNEX IVU.K.COMMERCIAL AIR TRANSPORT OPERATIONS[PART-CAT]
SUBPART BOPERATING PROCEDURESU.K.
SECTION 1U.K.Motor-powered aircraft
CAT.OP.MPA.215Use of headset — aeroplanesU.K.
(a)Each flight crew member required to be on duty in the flight crew compartment shall wear a headset with boom microphone or equivalent. The headset shall be used as the primary device for voice communications with ATS:U.K.
(1)
when on the ground:
(i)
when receiving the ATC departure clearance via voice communication; and
(ii)
when engines are running;
(2)
when in flight:
(i)
below transition altitude; or
(ii)
10 000 ft, whichever is higher;
and
(3)
whenever deemed necessary by the commander.
(b)In the conditions of (a), the boom microphone or equivalent shall be in a position that permits its use for two-way radio communications.U.K.