JP 3-50 National Search and Rescue Manual Vol I - US Navy

extended time, a Notice to Mariners should be issued in a
coastal area and a Navy Hydro message for ocean areas.
C. En route aircraft on IFR flight plans can be informed of
emergency situations in their vicinity by ARTCC, which is aware of and
able to communicate with aircraft available to assist. Under some
circumstances en route aircraft might be alerted by aircraft towers or
approach control facilities, usually when incidents occur in the
vicinity of these facilities. Alerting of aircraft should be done
during the Alert or Distress phases, when en route aircraft may
intercept and escort distressed craft, locate survivors transmitting on
aeronautical emergency frequencies, or sight the incident. SAR
coordinators should consult with aeronautical authorities in advance to
determine the best method of alerting en route aircraft in their area.
345 Medico Messages
A. Maritime and overseas SAR coordinators often become involved
with medical emergencies at sea. Medico messages request or transmit
medical advice from and to a ship.
B. Each medico message is a potential SAR mission. Medico
messages may be addressed to SAR coordinators from ships at sea.
Replies to such messages must indicate the medical facility which
provided the advice, to avoid the impression that the SAR Coordinator is
prescribing medical treatment.
C. Medico messages should be prefixed "DHMEDICO" to tell
communications personnel to handle them as medico messages. However,
fishing vessels and small craft will probably not know about this
procedure. Personnel who might be involved with such traffic should be
alert for incoming medico messages that can be identified as medico only
by the text.
D. Further information on radio medical advice to ships at sea is
contained in Defense Mapping Agency Hydrographic Topographic Center
publications 117A and 117B, Radio Navigational Aids.
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