Civil Aviation Act, 2009 (Act No. 13 of 2009)RegulationsCivil Aviation Regulations, 2011Part 121 : Air Transport Operations - Carriage on Aeroplanes of more than 19 Passengers or CargoSubpart 5 : Aeroplane Instruments and Equipment121.05.25 Microphones |
All flight crew members required to be on flight deck duty shall communicate through boom or throat microphones below the transition level/altitude.