ATS.OR.405 Use and availability of the VHF emergency frequency

(a)As laid down in Article 3d, the VHF emergency frequency (121,500 MHz) shall be used for genuine emergency purposes, including any of the following:

(1)to provide a clear channel between aircraft in distress or emergency and a ground station when the normal channels are being utilised for other aircraft;

(2)to provide a VHF communication channel between aircraft and aerodromes, not normally used by international air services, in case of an emergency condition arising;

(3)to provide a common VHF communication channel between aircraft, either civil or military, and between such aircraft and surface services, involved in common search and rescue operations, prior to changing when necessary to the appropriate frequency;

(4)to provide air-ground communication with aircraft when airborne equipment failure prevents the use of the regular channels;

(5)to provide a channel for the operation of emergency locator transmitters (ELTs), and for communication between survival craft and aircraft engaged in search and rescue operations;

(6)to provide a common VHF channel for communication between civil aircraft and intercepting aircraft or intercept control units and between civil or intercepting aircraft and air traffic services units in the event of interception of the civil aircraft.

(b)An air traffic services provider shall provide the frequency 121.500 MHz at:

(1)all area control centres and flight information centres;

(2)aerodrome control towers and approach control units serving international aerodromes and international alternate aerodromes;

(3)any additional location designated by the competent authority, where the provision of that frequency is considered necessary to ensure immediate reception of distress calls or to serve the purposes specified in point (a).