Introduction

As shown above a maritime VHF conversation consists of three obligatory exchanges:

I. MAKING CONTACT

II. EXCHANGE OF MESSAGES (central part of any VHF communication in which a station asks for or gives information, reaches agreement with another station, settles a request, etc.)

III. TERMINATION / END OF CONVERSATION

Here is a nine-step diagram showing a complete maritime conversation (cf. also SEASPEAK 1988):

CALLING STATIONRESPONDING STATION

		5. SWITCH OVER PROCEDURE

Steps 1 – 5 represent the MAKING CONTACT stage of conversation,

Steps 6 – 7 are the central part of a VHF conversation, i.e. MESSAGE EXCHANGE, and

Steps 8 – 9 are the final stage.

Here is an example of a complete standard maritime VHF communication:

Example:

Setting: Approaching pilot station – three miles from Elbe Lightvessel

Speakers: MV MARLIN, Elbe Pilot (EP)

Topic(s): Fourth notice of arrival – exchange with the pilot station;

		MARLIN: Elbe Pilot, Elbe Pilot. Elbe Pilot. This is Marlin, Marlin. Good evening. Over. Elbe Pilot: Marlin. This is Elbe Pilot. Switch to VHF Channel 2-2. Over. MARLIN: Elbe Pilot. This is Marlin, Agree: Switching to VHF Channel 2- 2. Over   …… switch-over procedure …..   Elbe Pilot: Marlin. This is Elbe Pilot. Question: What is your position. Over. MARLIN: Elbe Pilot, This Is Marlin. Answer: Position: Three miles from Elbe Lightvessel. Elbe Pilot: Marlin. This Is Elbe Pilot.Understood. Your position: Three miles from Elbe Lightvessel. Instruction: Rig pilot ladder on the port side, one foot above the water. Information: my position is close to Buoy No. 1. Over. MARLIN: Elbe Pilot. This is Marlin. Understood: I shall rig pilot ladder on the port side one foot above the water. Your position is close to Buoy No. 1. Thank you. Over. Elbe Pilot: Thank you very much indeed, Captain. Stand by on channel 1-6. Over. MARLIN: Elbe Pilot. Thank you. Standing by on VHF channel one - six. Out.
	C O N TATC

The above conversation is a combination of IMO SMCP recommended format, content and form of a VHF communication. Real conversation, however, may differ very much from the standard concerning their overall format, details of exchange, structure and wording used in the turns, wording of moves or acts, and sometimes even terminology. For transcripts of real VHF communications see end of Section II. (TRANSCRIPTS OF REAL VHF COMMUNICATIONS).

The above diagram therefore shows that a VHF conversation generally consist of three parts:

A. making contact (the call + reply + establishing contact on a working channel),

B. the message / exchange of messages (objective, purpose or focus of conversation)

C. termination or ending the conversation (with thanking)

A. MAKING CONTACT

Making a call (Calling)

Before transmitting, listen for a period long enough to ensure that harmful interference to transmissions already in progress is not likely to occur. If such interference seems likely, wait until the transmissions in progress are completed before making your call.

A station having a distress, urgency or safety message to transmit is entitled to interrupt a transmission of lower priority.

In making an initial call you may call:

- a single / specific ship or station (whose name and/or call sign you know) or

- a station whose name you do not know or when referring to all stations in a sea area.

Contact making includes the following steps:

1. initial call

2. response to initial call

3. indicating the working channel

4. agreeing/disagreeing with the working channel

5. switch-over procedure

Initial call consists of the following:

a) address the station you are calling (two or three times)

b) identify your own station

c) state the VHF channel on which you are calling

d) Turn-giving signal: Over.

Single Station Call

When establishing communications with a specific station, transmit the call sign of the station being called, followed by the call sign of the station making the call, as shown in the following example.

Example 1.: Single station call, name of the ship being called is known:

Example 2.: the name and call sign of the ship/station is known:

General Call (ALL SHIPS, ALL SHIPS, ALL SHIPS)

If the name of the station/ship is unknown:

When an operator wishes to establish communication with any station within range or in a certain area, the call should be made to ALL STATIONS or ALL SHIPS, using the same procedure as a single station call.

Example:

Coastal Radio Traffic Lists

At scheduled times, coastal or coast guard radio stations broadcast a list of telegrams and telephone calls they have on hand. An announcement, made on the calling frequencies and addressed to all stations, states that the traffic list will follow on a working frequency. However, these radio stations will transmit ONLY when they have traffic on hand.

Example on Channel 16:

Responding to initial call

When you hear a call directed to your station, reply as soon as possible. In your response you should (a) address the station, (b) identify your own station), and (c) finish your turn by saying OVER. You can advise the calling station to proceed with the message by means of the words GO AHEAD, or, if you are occupied, by saying STAND BY followed by the estimated number of minutes until your reply. Do not ignore the call. This may result in unnecessary calling, which uses up valuable air time in a crowded environment.

Example:

Replying to Calls when Information Is Missing

When you hear a call, but are uncertain the call is intended for your station, do not reply until the call is repeated and understood.

When your station is called but the identity of the calling station is uncertain, you should reply immediately, using the words:

Switching to a Working Channel

Switching to a working channel is normally carried out under the guidance of the Controlling Station (coast station, pilot station, port control, VTS, etc.), which is also responsible for establishing contact on the working channel. It follows immediately after contact has been established on the calling channel 16 or any watchkeeping channel. The phrase recommended by IMO SMCP is:

SWITCH TO (VHF CHANNEL) …

Other phrases commonly used are:

CHANGE TO …

GO TO …

Examples:

Calling Station

Responding Station

or

If the suggested channel is not available use the phrase:

VHF CHANNEL … UNABLE.

and then suggest another channel:

VHF CHANNELS AVAILABLE: …

or

VHF CHANNELS AVAILABLE: … THROUGH …

Example:

or

If the VHF channel has not been specified by the Controlling Station, the other station may ask the following:

QUESTION: WHICH VHF CHANNEL?

B. MESSAGE (EXCHANGE OF MESSAGES)

This is the central and most important part of any marine VHF communication or conversation. After establishing contact on the calling channel (16) and switching to and establishing contact on a working channel (indicated by the Controlling Station) the two stations (Calling Station and Responding Station) convey their communicative intention by exchanging their turns in one or more exchanges.

This may be any one or, more usually, a combination of the following:

- asking for information (e.g. on arrival at a port or VTS, strait, etc.)

- answering a question (e.g. on berthing arrangements)

- giving / providing information (e.g. on weather or traffic in a sea area)

- making a request (e.g. request for tugs)

- giving instructions and advice (e.g. where to anchor; keep clear)

- warning (e.g. heavy tow ahead)

- communicating intention (e.g. an intended manoeuvre)

- agreeing / disagreeing on a topic, etc. (e.g. on the number of tugs)

In the above cases ITU radio regulations and IMO SMCP recommend the use of message markers such as: QUESTION, ANSWER, INFORMATION, INSTRUCTION, ADVICE, REQUEST, INTENTION, WARNING. For more phrases consult Procedural (Standard) Words and Phrases above and examples of real (recorded) communication below.

In the message stage of the maritime VHF or and other radiotelephone conversation two stations (ship-to ship, ship-to-shore, shore-to-ship exchanges) ask for or give information, make requests, express intentions, give advice, give instructions, transmit warnings, etc. concerning the various topics, subjects and situations in navigation, navigation safety, manoeuvring, ship handling, avoiding collisions, environment protection, ship’s business, port regulations such as:

- distress, urgency and safety

- search and rescue

- requesting medical assistance

- meteorological information

- navigational warnings

- environmental protection

- helicopter operations

- ice-breaker operations

- vessel traffic services (VTS)

- traffic information

- route information

- navigational warnings

- navigational assistance

- vessel identification (+ position, course)

- traffic organisation service

- arrival, berthing and departure

- pilotage,

- towage

- anchoring

- port (inward/outward) clearance

- avoiding dangerous situations

- canal and lock operations, etc.

- cargo operations, etc.

For the phrases to be used in such situations see SMCP 2001, AI. EXTERNAL COMMUNICATIONS and SEASPEAK, Section V.

C. TERMINATION OF COMMUNICATIONS

When ending a conversation use the following format:

1. address

2. identify

3. respond to previous turn

4. expression of gratitude

5. Out.

To terminate communications, simply conclude your transmission with the

command OUT (which means " conversation is ended and no response is

expected).

Examples:

or