Distress, Urgency & Safety Communications:
Distress, Urgency & Safety Communications:
Sending a Distress Alert
What is usually the first step for a GMDSS Radio Operator to take when initiating a Distress priority message via Inmarsat?
What is usually the first step for a GMDSS Radio Operator to take when initiating a Distress priority message via Inmarsat?
(A) By pressing a "Distress Button" or "Distress Hot Key(s)" on the equipment.
It is the actual step to execute. The Distress call before this system was in place, was to transmit the SOS signal on 500 kHz, by a trained radio operator in the Morse Code.
For more information, please see Furuno's pdf GMDSS Guide
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Which of the following statements is true regarding Distress alerting under GMDSS?
Which of the following statements is true regarding Distress alerting under GMDSS?
(B). The Distress alert should identify the station in Distress and its position & time of position update. Also, the alert may include the nature of the Distress, the type of assistance required, or the course and speed of the mobile unit.
§ 80.314 Distress communications.
47 CFR 80.314(c) The radiotelephone distress call consists of:
(1) The distress signal MAYDAY spoken three times;
(2) The words THIS IS;
(3) The call sign (or name, if no call sign assigned) of the mobile station in distress, spoken three times;
(4) Particulars of the station's position;
(5) The nature of the distress;
(6) The kind of assistance desired; and
(7) Any other information which might facilitate rescue, for example, the length, color, and type of vessel, or number of persons on board.
For more information, please see Code of Federal Regulations Title 47 Chapter I Subchapter D Part 80 Distress communications.
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If a GMDSS Radio Operator initiates a DSC Distress transmission but does not insert a message, what happens?
If a GMDSS Radio Operator initiates a DSC Distress transmission but does not insert a message, what happens?
(C). The transmission will be made with "default" information provided automatically.
From RECOMMENDATION ITU-R M.541-9 titled Operational procedures for the use of digital selective-calling equipment in the maritime mobile service
3.1 Transmission by a mobile unit in distress
3.1.2 If the position of the ship cannot be entered, then the position information signals shall be transmitted automatically as the digit 9 repeated ten times.
From Code of Federal Regulations Title 47 Chapter I Subchapter D Part 80 Subpart W Operating Procedures for Distress and Safety Communications:
47 CFR 80.5 “Automatic Identification Systems (AIS)”
A maritime navigation safety communications system standardized by the International Telecommunication Union (ITU) and adopted by the International Maritime Organization (IMO) that provides vessel information, including the vessel's identity, type, position, course, speed, navigational status and other safety-related information automatically to appropriately equipped shore stations, other ships, and aircraft; receives automatically such information from similarly fitted ships; monitors and tracks ships; and exchanges data with shore-based facilities.
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Repetition of a DSC Distress alert is normally automatic if not acknowledged after a delay of:
Repetition of a DSC Distress call is normally automatic if not acknowledged after a delay of:
(D) 3.5 - 4.5 minutes
3.1.3.1 Single frequency call attempt A distress alert attempt should be transmitted as 5 consecutive calls on one frequency. To avoid call collision and the loss of acknowledgements, this call attempt may be transmitted on the same frequency again after a random delay of between 3½ and 4½ min from the beginning of the initial call.
For more details, please see RECOMMENDATION ITU-R M.541-9 titled Operational procedures for the use of digital selective-calling equipment in the maritime mobile service
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For a MF/HF DSC Distress alert which statement is FALSE?
For a MF/HF DSC Distress call which statement is FALSE?
(A). It always requests J3E Voice follow-on communications so other vessels can hear the Mayday.
T R U E :
MF/HF DSC Distress call:
will send the minimal necessary information using the "Distress Button" or "Distress Hot Key."
will send a more detailed Distress format if time permits and operator data entries are correctly performed.
does NOT contain all the information normally of interest in on-scene Distress communications.
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Which statement regarding an MF/HF DSC Distress alert is true:
Which statement regarding an MF/HF DSC Distress call is TRUE:
(B). Follow on communications should be presumed to take place on the voice frequency associated with the specific DSC frequency used.
3.1.3 Distress alert attempt
At MF and HF a distress alert attempt may be transmitted as a single frequency or a multi-frequency call attempt. At VHF only single frequency call attempts are used.
For more details, please see RECOMMENDATION ITU-R M.541-9 titled Operational procedures for the use of digital selective-calling equipment in the maritime mobile service
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