Jack Ranga,
ahhh no,you are incorrect:
4 Distress and Urgency Messages
4.1 Pilots have been advised that, in the event of an emergency situation, an ATSU can
only provide the necessary priority and handling if the controller is made aware of the
emergency by the crew’s formal declaration on the RTF. Pilots have also been
advised that the extent to which an ATSU will be able to offer assistance will depend
on the amount of information provided and on its being transmitted at the earliest
opportunity. Furthermore, it is preferable that if pilots believe that they are facing an
emergency situation, to declare it as early as possible and cancel it later if they decide
that the situation allows.
4.2 There are two classes of emergency message:
Distress: A condition of being threatened by serious and/or imminent danger and
of requiring immediate assistance.
Urgency: A condition concerning the safety of an aircraft or other vehicle, or of
some person on board or within sight, but which does not require
immediate assistance.
4.3 The message will contain as many as possible of the following items:
MAYDAY, MAYDAY, MAYDAY (for distress messages)
or
PAN PAN, PAN PAN, PAN PAN (for urgency messages)
and
Name of the station addressed (time and circumstances permitting)
Identification of the aircraft
Nature of the emergency
Intention of the person in command
Present position, level and heading
Distress: A condition of being threatened by serious and/or imminent danger and
of requiring immediate assistance.
Urgency: A condition concerning the safety of an aircraft or other vehicle, or of
some person on board or within sight, but which does not require
immediate assistance.
http://www.caa.co.uk/docs/33/CAP493Part1adv.pdf
(from ICAO Annex 12)