Commonwealth Numbered Regulations

1988 NO. 158 CIVIL AVIATION REGULATIONS - REG 193

193. (1) The following signals, used either together or separately, shall be
used by an aircraft for the purpose of giving notice of difficulties which
compel it to land without requiring immediate assistance:

   (a)  the repeated switching on and off of the landing lights;

   (b)  the repeated switching on and off of the navigation lights, in such a
        manner as to be distinctive from the flashing lights described in
        subregulation 196 (2);

   (c)  a succession of white pyrotechnical lights.

(2) The following signals, used either together or separately, shall be used
by an aircraft for the purpose of giving notice that the aircraft has a very
urgent message to transmit concerning the safety of a ship, aircraft or
vehicle, or of some person on board or within sight:

   (a)  in radiotelegraphy, 3 repetitions of the group XXX (- . . - - . . - -
        . . -), sent with the letters of each group, and the successive groups
        clearly separated from each other, and sent before the transmission of
        the message;

   (b)  in radiotelephony, 3 repetitions of the words PAN, PAN, sent before
        the transmission of the message;

   (c)  a succession of green pyrotechnical lights;

   (d)  a succession of green flashes with signal apparatus.