How Warships Communicate During Unplanned Encounters
    2014-04-24 19:05:29       Web Editor: Min

Standard chart of "International Flags and Pennants" of the International Code of Signals which the Code of Conduct for Unplanned Encounters at Sea (CUES) used to indicate the source of signals. [Photo: Agencies]

Naval chiefs from 25 Asia-Pacific countries have adopted an agreement to avoid miscommunication between naval vessels and thus prevent possible conflict.

The Code of Conduct for Unplanned Encounters at Sea, or CUES was passed during the 14th Western Pacific Naval Symposium (WPNS) in east China's Qingdao on Tuesday.

The CUES provides standard procedures in relation to the use of sound, lights, flag signals, radio communications, call signs, voice procedures and the exchange of key information for unplanned encounters between naval ships of the WPNS countries.

According to the CUES, when using flag signals from the International Code of Signals (ICS) for communications between warships, the code pennant should be used to indicate the source of those signals.

CUES also requires all voice communications be conducted in English unless otherwise agreed upon, and all messages should include addressee(s), originator, text, over, out.

The CUES document is not legally binding for the participating nations but represents an agreement of standardized protocols designed to minimize communication failure between naval ships and aircraft during unplanned encounters at sea, according to the official website of China's Defense Ministry.

The Western Pacific Naval Symposium comprises 21 member countries and three observers within the region. Pakistan is currently applying for observer status.

The 15th Western Pacific Naval Symposium will be held in Indonesia.

Communication procedures are listed as below:

Applicability to Naval Aircraft

Naval aircraft should comply with the communications procedures set out in this document to the extent that they are able. Naval aircraft will not normally use the signal groups provided but, instead, will comply with international protocols applicable to air navigation.

Sound, Light and Flag Signals

When naval ships are operating in sight of one another or in restricted visibility, such signals (flag, light, sound) as are prescribed in the International Regulations for Preventing Collisions at Sea should be used to signal intentions related to manoeuvres being undertaken in accordance with those Regulations.

When using flag signals from the International Code of Signals (ICS) for communications between warships, the CODE pennant should be used to indicate the source of those signals.

Radio Communications

So that communications between naval ships and naval aircraft during unplanned encounters at sea are established in a timely manner and for reasons of efficiency, radio communications are the preferred method of communicating information contained in CUES.

Call Signs

Individual ship call signs will be ship NAME, or HULL NUMBER, or INTERNATIONAL RADIO SIGNAL CALLSIGN. Aircraft call signs will be the aircraft INTERNATIONAL RADIO SIGNAL CALLSIGN. Ships and aircraft should also identify their nationality.

Where the call sign of the platform being called is unknown, it should be addressed as UNKNOWN STATION with sufficient supplementary information, for example position course and speed, to alert the station that it is being called. Units called as UNKNOWN STATION should answer using their INTERNATIONAL RADIO SIGNAL CALLSIGN.

Voice Procedures

All voice communications should be conducted in ENGLISH unless otherwise agreed upon.

All messages are to include:
a) Addressee(s). The command or commands for whom the message is intened.
b) Originator Standard terminology THIS IS followed by the INTERNATIONAL RADIO SIGNAL CALLSIGN is to be used to indicate the message originator¡¯s identity.
c) Text. The message being sent, using the Selected Signals Vocabulary where possible.
d) Over. An invitation to transmit.
e) Out. When no reply is required.

Exchange of Key Information

In the interest of safety, on making initial contact, and after exchanging identities, Commanding Officers or Masters (as applicable) may elect to deconflict movement and operations by exchanging key elements of information between forces. This information may include unit position and current manoeuvring intentions, when appropriate. The decision to exchange data is left to the Commanding Officer or Master (as applicable) and nothing in this code is meant to imply that information exchange is required.

Tack Line

The tack line is transmitted and spoken as TACK and written as a dash. It is used:
a) To avoid ambiguity by separating signals or groups of numbers which if not separated could convey a different meaning to that intended, for example G Corpen 000-10.
b) When required by a particular signal, for example AV 26-3

Execution of Voice and Flag Signals

Signals may be executed by time or by the delayed executive method.

When not using the delayed executive method, a time group inserted after the text indicates that the action is to be taken upon receipt, for example TA 89 TACK Time 2120 ZULU.

When action is to be commenced or completed at a future time and without further orders, a ¡°T¡± group is to be included in the text, for example TA 89 TACK TANGO 2145 ZULU TACK Time 2120 ZULU.

Delayed Executive Method of Signalling

When using tactical signal groups from the Selected Signals Vocabulary and it is intended that they be carried out by executive order, the delayed executive method is to be used, leaving sufficient time available for decode to occur in receiving stations. The text is to be repeated during each transmission.

Preliminary. The text of the first transmission of a tactical signal group is to be prefixed with the words EXECUTE TO FOLLOW which is to be followed by the tactical group. For example: Execute to follow TURN PORT 270 I say again TURN PORT 270.

Executive. The text of the executive transmission of a tactical signal group is to be followed by the words STANDBY EXECUTE. For example: TURN PORT 270 Standby Execute I say again TURN PORT 270 Standby Execute.

Designation (DESIG) Signal

The DESIG signal is used to describe own or other forces or to indicate that the information that follows is not a signal group and is to be interpreted as spoken.



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