Paragraph 64 Distress, urgency and safety signals

(1)

The following signals, given either together or separately before the sending of a message, signify that an aircraft is threatened by grave and imminent danger and requests immediate assistance—

(a)

by radiotelephony–

the spoken word ‘MAYDAY’;

(b)

by visual signalling–

(i)

the signal SOS (… --- …);

(ii)

a succession of pyrotechnic lights fired at short intervals each showing a single red light;

(iii)

a parachute flare showing a red light;

(c)

by sound signalling other than radiotelephony–

(i)

the signal SOS (… --- …);

(ii)

a continuous sounding with any sound apparatus.

(2)

The following signals, given either together or separately, before the sending of a message, signify that the pilot-in-command of the aircraft wishes to give notice of difficulties which compel it to land but that he does not require immediate assistance—

(a)

a succession of white pyrotechnic lights;

(b)

the repeated switching on and off of the aircraft landing lights;

(c)

the repeated switching on and off of its navigation lights, in such a manner as to be clearly distinguishable from the flashing navigation lights described in rule 49.

(3)

The following signals, given either together or separately, indicate that the pilot-in-command of the aircraft has an urgent message to transmit concerning the safety of a ship, aircraft, vehicle or other property or of a person on board or within sight of the aircraft from which the signal is given—

(a)

by radiotelephony—

the repeated spoken word, ‘PAN PAN’;

(b)

by visual signalling—

the signal XXX (- .. -- .. -- .. -);

(c)

by sound signalling other than radiotelephony—

the signal XXX (- .. -- .. -- .. -).