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GOC GMDSS Exam study materials
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GOC GMDSS Exam practice questions

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Question 1Distress, urgency and safety communications procedures

Which frequency band is reserved for distress, urgency and safety communications in the Global Maritime Distress and Safety System?

  1. The 27 MHz citizens band
  2. The 9 GHz maritime radar band
  3. The 121.5 MHz aeronautical emergency band
  4. The 156.525 MHz band used for digital selective calling Correct answer.

Explanation

GMDSS reserves specific channels and frequencies, and 156.525 MHz (VHF channel 70) is dedicated to digital selective calling for distress, urgency and safety alerts. Voice distress traffic on VHF is carried on channel 16 at 156.800 MHz. The other bands listed serve different purposes and are not GMDSS distress alerting channels.

Question 2Distress, urgency and safety communications procedures

What does the DSC alert in the distress category automatically include when transmitted from a GMDSS vessel?

  1. The vessel's identity, position and time of the alert Correct answer.
  2. The names of all crew members on board
  3. The vessel's insurance details and port of registry
  4. The master's name and the cargo manifest

Explanation

A distress DSC alert carries the vessel's Maritime Mobile Service Identity, the nature of distress, and where available the position and time of the alert. This allows coast stations and other vessels to identify and locate the casualty immediately. Crew lists, cargo and insurance information are not part of the DSC message format.

Question 3Distress, urgency and safety communications procedures

On which VHF channel is radiotelephony distress, urgency and safety traffic normally conducted?

  1. Channel 06
  2. Channel 70
  3. Channel 13
  4. Channel 16 Correct answer.

Explanation

VHF channel 16 (156.800 MHz) is the international radiotelephony distress, urgency and safety channel. It is used for the initial distress call and for establishing contact before moving to a working channel. Channel 70 is reserved for DSC only and must not carry voice traffic.

Question 4Distress, urgency and safety communications procedures

What is the correct priority order of the three GMDSS message categories, from highest to lowest?

  1. Safety, distress, urgency
  2. Distress, urgency, safety Correct answer.
  3. Distress, safety, urgency
  4. Urgency, distress, safety

Explanation

Distress has the highest priority, followed by urgency, then safety. Distress concerns grave and imminent danger requiring immediate assistance, urgency concerns a serious situation not yet requiring immediate assistance, and safety concerns navigation or weather warnings. This hierarchy governs how traffic is handled on shared frequencies.

Question 5Distress, urgency and safety communications procedures

Which signal word identifies a distress message in radiotelephony?

  1. SILENCE
  2. MAYDAY Correct answer.
  3. PAN PAN
  4. SECURITE

Explanation

The spoken word MAYDAY, derived from the French m'aidez, signals that a vessel is in grave and imminent danger and requires immediate assistance. It is repeated three times at the start of a distress call. PAN PAN is for urgency and SECURITE for safety.

Question 6Distress, urgency and safety communications procedures

What does the spoken urgency signal PAN PAN indicate?

  1. A request to impose radio silence
  2. A vessel actually sinking with persons in the water
  3. A routine weather forecast for the area
  4. A serious situation that does not yet require immediate assistance Correct answer.

Explanation

PAN PAN, repeated three times, announces an urgent message concerning the safety of a vessel or person but without immediate danger of loss. Examples include engine breakdown or a medical case that is serious but not life-threatening. If the situation deteriorates into grave and imminent danger, the signal changes to MAYDAY.

Question 7Distress, urgency and safety communications procedures

What is the purpose of the spoken safety signal SECURITE?

  1. To test the DSC equipment
  2. To announce a message concerning navigation or meteorological safety Correct answer.
  3. To request immediate medical evacuation
  4. To declare that a vessel is abandoning ship

Explanation

SECURITE, repeated three times, precedes a safety message such as a gale warning, navigational hazard or other important notice. It has the lowest priority of the three signal words. It is never used to declare distress or to request urgent assistance.

Question 8Distress, urgency and safety communications procedures

Which device is a GMDSS satellite service used for distress alerting and two-way communications?

  1. Inmarsat Correct answer.
  2. SART
  3. Navtex
  4. EPIRB

Explanation

Inmarsat is the satellite communications system in GMDSS providing distress alerting and two-way voice and data communications. Navtex, SART and EPIRB are separate GMDSS elements with different functions. Inmarsat terminals allow direct contact with rescue coordination centres.

Question 9Distress, urgency and safety communications procedures

A vessel's engine has failed and it is drifting toward a rocky shore, but there is no immediate danger of sinking. Which signal should be used to announce this situation?

  1. MAYDAY
  2. PAN PAN Correct answer.
  3. SILENCE
  4. SECURITE

Explanation

A drifting vessel with engine failure faces a serious situation but is not yet in grave and imminent danger, so urgency applies and PAN PAN is used. If the vessel grounds or begins to sink, the situation escalates to distress and MAYDAY is used. SECURITE is for safety information only.

Question 10Distress, urgency and safety communications procedures

When transmitting a MAYDAY distress call by radiotelephony, which element comes immediately after the MAYDAY signal is repeated three times?

  1. The nature of the distress
  2. The vessel's position in latitude and longitude
  3. The number of persons on board
  4. The words THIS IS followed by the vessel's name and call sign Correct answer.

Explanation

The distress call format begins with MAYDAY repeated three times, then THIS IS, then the vessel's identity such as name and call sign. The distress message that follows then gives position, nature of distress and assistance required. Identity comes before the detailed content of the message.

Question 11Distress, urgency and safety communications procedures

Which of these is included in a complete radiotelephone distress message?

  1. The nature of the distress and the assistance required Correct answer.
  2. The names of the rescue vessels already dispatched
  3. The vessel's next port of call
  4. The vessel's cargo and freight charges

Explanation

A distress message states the vessel's identity, position, nature of distress, assistance required and other useful information such as persons on board. This allows rescue coordination to plan an appropriate response. Commercial voyage details are irrelevant to the emergency.

Question 12Distress, urgency and safety communications procedures

What is the correct response by another vessel that hears a distress alert but is not in a position to assist?

  1. It should immediately transmit its own MAYDAY to attract attention
  2. It should switch off its radio to avoid interference
  3. It should broadcast a SECURITE message about the casualty
  4. It should maintain silence and, if possible, monitor the frequency for further traffic Correct answer.

Explanation

A station unable to assist should not transmit unnecessarily, as this can interfere with the distress traffic. It should keep watch on the distress frequency and stand by for further instructions from the rescue coordination centre or the on-scene coordinator. Silence on the air is itself a form of assistance to the casualty.

Question 13Distress, urgency and safety communications procedures

What does the procedure word SILENCE mean when transmitted three times during distress traffic?

  1. The distress is cancelled and normal working may resume
  2. All stations are to abandon the frequency permanently
  3. All stations are to cease transmissions that interfere with the distress traffic Correct answer.
  4. The sender is requesting a radio check

Explanation

SILENCE repeated three times, usually by the station controlling the distress traffic, orders all other stations to stop transmitting so that the casualty and rescue stations can communicate. It does not cancel the distress or close the frequency. Normal use resumes only when the controlling station says so.

Question 14Distress, urgency and safety communications procedures

How is a distress alert that was transmitted in error properly cancelled?

  1. By sending a routine position report on a working channel
  2. By simply switching off the DSC equipment without any transmission
  3. By transmitting a distress cancellation message on the same frequency identifying the station and stating the alert was a mistake Correct answer.
  4. By waiting for a coast station to notice the error

Explanation

A false distress alert must be cancelled immediately by transmitting a cancellation on the frequency used, identifying the station and stating that the alert was inadvertent. This prevents unnecessary search and rescue action. Failing to cancel is an offence and wastes rescue resources.

Question 15Distress, urgency and safety communications procedures

What is the function of a NAVTEX receiver in the GMDSS?

  1. It automatically receives maritime safety information broadcasts such as navigational and weather warnings Correct answer.
  2. It provides two-way voice communication with coast stations
  3. It transmits the vessel's position to satellites in an emergency
  4. It locates survivors by radar on the scene

Explanation

NAVTEX is a terrestrial automatic direct-printing system that receives maritime safety information, including navigational warnings, meteorological warnings and search and rescue information. It operates on a dedicated medium-frequency channel and prints or displays messages without operator action. It is a receive-only safety service.

Question 16Distress, urgency and safety communications procedures

What is the primary function of a SART in a distress situation?

  1. To receive weather warnings automatically
  2. To help searching vessels locate the survival craft by radar Correct answer.
  3. To provide voice communication with aircraft
  4. To transmit a satellite distress alert with the vessel's identity

Explanation

A search and rescue radar transponder responds to interrogating radar signals by producing a distinctive series of dots on the searching vessel's radar display, allowing the survival craft to be located. It operates in the 9 GHz band and is activated manually when abandoning ship. It does not transmit satellite alerts or carry voice.

Question 17Distress, urgency and safety communications procedures

What is the function of an EPIRB in the GMDSS?

  1. To provide radar location of the survival craft
  2. To enable two-way voice communication with rescue centres
  3. To transmit a distress alert to the satellite system that identifies the vessel and its position Correct answer.
  4. To receive navigational warnings automatically

Explanation

An emergency position-indicating radio beacon transmits a distress alert via the satellite system, providing the vessel's identity and, for float-free beacons, a position derived from the satellite system. It is the primary means of alerting when a vessel sinks suddenly. It does not provide voice communication.

Question 18Distress, urgency and safety communications procedures

Which of these is the correct spoken distress call when transmitted by radiotelephony?

  1. MAYDAY, THIS IS [vessel name], OVER AND OUT
  2. SECURITE SECURITE SECURITE, THIS IS [vessel name]
  3. PAN PAN PAN PAN PAN PAN, THIS IS [vessel name]
  4. MAYDAY MAYDAY MAYDAY, THIS IS [vessel name and call sign] Correct answer.

Explanation

The distress call consists of MAYDAY repeated three times followed by THIS IS and the vessel's identity. The distress message then follows. Using PAN PAN or SECURITE would misclassify the emergency, and the phrase OVER AND OUT is not part of the distress call.

Question 19Distress, urgency and safety communications procedures

During a distress situation, a vessel hears another station transmitting on the distress frequency and blocking the casualty. What procedure can the controlling station use?

  1. Change to a working channel and ignore the interference
  2. Transmit a SECURITE message to warn all stations
  3. Transmit the word SILENCE three times to impose radio silence Correct answer.
  4. Transmit a PAN PAN to request priority

Explanation

The station controlling the distress traffic may transmit SILENCE three times to order all other stations to stop transmitting. This clears the frequency so the casualty and rescue stations can communicate. The order remains in force until the controlling station lifts it.

Question 20Distress, urgency and safety communications procedures

A vessel sends a MAYDAY alert but the situation is resolved before rescue services arrive. What must the sending station do?

  1. Transmit a SECURITE message about the vessel's position
  2. Transmit a distress cancellation message stating that the distress no longer exists and normal working may resume Correct answer.
  3. Simply resume normal working without any further transmission
  4. Wait for the rescue coordination centre to cancel the alert

Explanation

When a distress situation no longer exists, the station that originated the distress must transmit a cancellation message. This message announces that the distress has ended and that normal working may resume, so that rescue assets can stand down. Silence would leave searching vessels committed to an unnecessary operation.

Question 21Distress, urgency and safety communications procedures

Which of these statements best explains why the distress frequency must be kept clear of routine traffic?

  1. Routine traffic improves the range of distress transmissions
  2. Routine traffic is required to keep the frequency active
  3. Routine traffic on the distress frequency could block a genuine distress call and delay rescue Correct answer.
  4. Routine traffic on the distress frequency is permitted because it has no effect on rescue

Explanation

The distress frequency is a shared resource that must remain available for emergency calls. Routine or unnecessary transmissions can mask a weak distress signal and delay the response, potentially costing lives. This is why the frequency is reserved for distress, urgency and safety traffic only.

Question 22Distress, urgency and safety communications procedures

A vessel receives a distress alert from another vessel and is the nearest ship. What is the correct first action?

  1. Continue on the planned voyage because the alert may be a false alarm
  2. Wait for a coast station to instruct it before taking any action
  3. Acknowledge the distress and proceed to assist while informing the rescue coordination centre Correct answer.
  4. Transmit a SECURITE message to warn other vessels

Explanation

Under the duty to assist, a vessel that hears a distress alert should acknowledge it if it is able to assist and proceed to the casualty's position, informing the rescue coordination centre. Delaying to await instructions can waste critical time. The obligation applies to masters of vessels at sea.

Question 23Distress, urgency and safety communications procedures

How should a distress alert be relayed by a station that is not itself in distress?

  1. By transmitting a SECURITE message with the casualty's position
  2. By transmitting a MAYDAY RELAY call identifying the station and the casualty Correct answer.
  3. By transmitting a PAN PAN call identifying the station
  4. By sending a routine message to the nearest coast station

Explanation

A station relaying a distress alert uses the MAYDAY RELAY procedure, identifying itself and passing on the casualty's details. This tells all stations that the message is a relay and not a new distress. A relay is used when the casualty cannot communicate directly or when the alert needs wider dissemination.

Question 24Distress, urgency and safety communications procedures

What is the correct radiotelephone distress message content when the vessel's position is unknown?

  1. Give an approximate position in a different coordinate system
  2. State a position for the nearest port instead of the vessel
  3. State that the position is unknown and give the last known position or a description of the area Correct answer.
  4. Omit the position entirely and give only the nature of distress

Explanation

If the exact position is not known, the message should say so and give the last known position or a description of the area to help rescuers. Omitting position information makes search and rescue much harder. Accuracy and honesty about uncertainty are essential.

Question 25Distress, urgency and safety communications procedures

What is the meaning of the spoken phrase OVER when used in radiotelephony?

  1. The conversation is finished and no reply is expected
  2. The sender is cancelling a distress alert
  3. The sender is requesting a radio check
  4. The sender has finished speaking and expects a reply Correct answer.

Explanation

OVER indicates that the sender has finished transmitting and is inviting the other station to reply. It is used to keep the exchange orderly, especially on shared distress frequencies. OUT, by contrast, means the exchange is complete and no reply is expected.

Question 26Distress, urgency and safety communications procedures

In a radiotelephone distress call, which spoken phrase immediately follows the distress signal MAYDAY when a coast station is being addressed?

  1. The vessel's call sign spoken twice
  2. The name of the called station, spoken once Correct answer.
  3. The words COME IN PLEASE
  4. The words THIS IS repeated once

Explanation

The standard distress call format is MAYDAY, MAYDAY, MAYDAY followed by the words THIS IS, then the identity of the calling station. When a specific station is being addressed, its name is spoken once before the calling station's identity. This ordering lets all listening stations recognise the distress priority at once.

Question 27Distress, urgency and safety communications procedures

Which spoken proword is used in radiotelephony to separate the text of a message from its addressee and to mark the end of the transmission?

  1. ROGER
  2. WILCO
  3. OVER Correct answer.
  4. OUT

Explanation

OVER is the procedural word that indicates the transmitting station has finished speaking and expects a reply, so it marks the end of a transmission. It is used to hand the channel to the other station. ROGER and WILCO are receipt prowords, and OUT closes a exchange with no reply expected.

Question 28Distress, urgency and safety communications procedures

A vessel at sea observes a person overboard and requires immediate assistance from other ships in the area, but the vessel itself is not in grave and imminent danger. Which signal should be transmitted?

  1. SECURITE
  2. MAYDAY
  3. PAN PAN Correct answer.
  4. A DSC routine call

Explanation

PAN PAN is the urgency signal, used when a station has a very urgent message concerning the safety of a vessel or person but is not in immediate danger. A person overboard with recovery in progress fits urgency rather than distress. MAYDAY is reserved for grave and imminent danger requiring immediate assistance.

Question 29Distress, urgency and safety communications procedures

Under the GMDSS, which radiotelephone frequency is designated for distress, urgency and safety traffic in the VHF band?

  1. Channel 70
  2. Channel 16 Correct answer.
  3. Channel 13
  4. Channel 06

Explanation

VHF Channel 16 on 156.8 MHz is the international distress, safety and calling frequency for radiotelephony. It is monitored for distress alerts and used to establish contact before moving to a working channel. Channel 70 is the VHF DSC channel and is not used for voice.

Question 30Distress, urgency and safety communications procedures

What is the meaning of the spoken proword SEELONCE MAYDAY when transmitted by the station controlling distress traffic?

  1. The distress traffic has ended and normal working may resume
  2. All stations must stop transmitting until the distress is ended Correct answer.
  3. Only stations in the immediate area may continue to transmit
  4. Silence is imposed because of a navigation hazard message

Explanation

SEELONCE MAYDAY is imposed by the station in control of distress traffic to silence all stations except the one in distress and those assisting. It remains in force until the controller cancels it. It is not a cancellation of the distress itself.

Question 31Distress, urgency and safety communications procedures

A ship in distress transmits a MAYDAY call and message on VHF Channel 16. Which station should normally coordinate the distress traffic and impose silence if interference occurs?

  1. The vessel in distress itself, throughout the entire operation
  2. The station with the strongest transmitter in the area
  3. Any ship that happens to hear the transmission first
  4. The nearest coast station or the station designated by the vessel in distress Correct answer.

Explanation

Distress traffic should be controlled by the coast station or the search and rescue authority responsible for the area, or by a station designated by the vessel in distress. That controller regulates the traffic and imposes silence when necessary. Other stations assist but do not take control unless designated.

Question 32Distress, urgency and safety communications procedures

When a distress alert has been received by DSC and the vessel is known to be in distress, what is the recommended radiotelephone follow-up on VHF?

  1. A DSC acknowledgement sent on Channel 70
  2. A MAYDAY relay transmitted by every receiving station
  3. A MAYDAY call and message transmitted by the distressed vessel on Channel 16 Correct answer.
  4. A SECURITE message announcing the alert

Explanation

After a DSC distress alert, the distressed vessel should follow up with a MAYDAY call and message on the associated radiotelephone distress frequency. This gives voice details such as position, nature of distress and assistance required. The follow-up is made by the vessel in distress, not by every receiver.

Question 33Distress, urgency and safety communications procedures

Which information should a vessel include when transmitting a MAYDAY RELAY on behalf of a distress casualty?

  1. Only the words MAYDAY RELAY and the relaying vessel's call sign
  2. The relaying vessel's own cargo details and voyage plan
  3. The coast station's telephone and telex numbers
  4. The identity of the casualty, its position, and the distress information received Correct answer.

Explanation

A MAYDAY RELAY must pass on the identity of the station in distress, its position and the substance of the distress information received, so that rescue authorities can act. The relaying station identifies itself after THIS IS. Superfluous information about the relay vessel delays the alert.

Question 34Distress, urgency and safety communications procedures

A vessel receives a distress alert on VHF DSC from a ship several hundred miles away, well outside the vessel's area of operation. What action is most appropriate?

  1. Ignore the alert because the distance is too great
  2. Broadcast a MAYDAY RELAY to all stations
  3. Do not acknowledge, and allow a station nearer the casualty to respond Correct answer.
  4. Acknowledge the alert and proceed to the scene

Explanation

Stations that receive a distress alert but are not in a position to assist should not acknowledge it, because acknowledgement may cause the casualty to stop further alerting. A station closer to the casualty, or a coast station, should acknowledge and coordinate. The distant vessel should maintain a listening watch and assist only if later requested.

Question 35Distress, urgency and safety communications procedures

What is the correct action for a station that has transmitted a DSC distress alert in error before any acknowledgement has been received?

  1. Wait for a coast station to ask for clarification
  2. Transmit a DSC distress cancellation on the distress channel and follow up by radiotelephony Correct answer.
  3. Send a routine DSC call to the nearest coast station
  4. Switch off the equipment and wait for the battery to drain

Explanation

A false distress alert must be cancelled promptly using the appropriate DSC cancellation procedure on the distress channel, followed by a radiotelephone broadcast on the associated distress frequency. The broadcast should identify the station and state that the alert was transmitted in error. Waiting allows an unnecessary search and rescue response to develop.

Question 36Distress, urgency and safety communications procedures

Which of these is the correct radiotelephone urgency call and message structure for a vessel reporting a serious medical problem that is not immediately life-threatening?

  1. SECURITE, SECURITE, SECURITE, ALL STATIONS, THIS IS, then the medical details
  2. PAN PAN, PAN PAN, PAN PAN, ALL STATIONS, THIS IS, vessel identity, then the urgency message Correct answer.
  3. PAN PAN, THIS IS, vessel identity, then the urgency message without repeating the signal
  4. MAYDAY, MAYDAY, MAYDAY, ALL STATIONS, THIS IS, then the medical details

Explanation

The urgency call consists of the signal PAN PAN spoken three times, the addressee ALL STATIONS, the words THIS IS, and the identity of the calling station, followed by the urgency message. Repeating the signal three times marks the priority clearly. The full structure ensures all stations recognise the urgency category.

Question 37Distress, urgency and safety communications procedures

A coast station needs to broadcast a gale warning and a navigational hazard notice to all ships. Which signal introduces this radiotelephone broadcast?

  1. SILENCE
  2. SECURITE Correct answer.
  3. MAYDAY
  4. PAN PAN

Explanation

SECURITE, spoken three times, is the safety signal that introduces a message about navigation safety or meteorological warnings. It has lower priority than distress and urgency but is still protected traffic. The message should be followed by the station identity and the safety information.

Question 38Distress, urgency and safety communications procedures

During a distress incident, a station that is not the controlling station hears several vessels transmitting routine traffic on the distress frequency. What should it do?

  1. Switch off its receiver to avoid the interference
  2. Join the routine traffic to ask the vessels to move
  3. Remain silent and inform the station controlling the distress traffic Correct answer.
  4. Transmit SILENCE MAYDAY three times and take control of the traffic

Explanation

Only the station controlling the distress traffic, normally the coast station or the station designated by the casualty, imposes silence. Other stations should remain silent and, if possible, inform the controller of the interference. This preserves the authority of the controller and avoids conflicting instructions.

Question 39Distress, urgency and safety communications procedures

What is the purpose of the proword SEELONCE FINI in radiotelephony?

  1. To warn of a hazard to navigation in the area
  2. To indicate that distress traffic has ended and silence is lifted Correct answer.
  3. To request that all stations repeat their last transmission
  4. To transfer control of distress traffic to another station

Explanation

SEELONCE FINI is transmitted by the station controlling distress traffic to announce that the distress has ended and normal working may resume. It lifts the silence previously imposed. It is normally preceded by the distress signal and the identity of the controlling station.

Question 40Distress, urgency and safety communications procedures

A vessel's radio operator is unsure whether a situation qualifies as distress or urgency. Which principle should guide the choice of signal?

  1. Use MAYDAY only when there is grave and imminent danger requiring immediate assistance Correct answer.
  2. Use PAN PAN for all situations because it is less likely to cause alarm
  3. Use MAYDAY whenever any assistance is wanted, to guarantee a fast response
  4. Use SECURITE until another station confirms the situation is serious

Explanation

The distinction rests on whether the vessel or person faces grave and imminent danger and needs immediate assistance. If so, MAYDAY is correct; if the message is urgent but the danger is not immediate, PAN PAN applies. Misusing MAYDAY for lesser situations undermines the credibility of the distress priority.

Question 41GMDSS system architecture, sea areas and carriage requirements

Under the GMDSS, which sea area is defined as the area within radiotelephone coverage of at least one VHF coast station in which continuous DSC alerting is available?

  1. Sea area A3
  2. Sea area A1 Correct answer.
  3. Sea area A2
  4. Sea area A4

Explanation

Sea area A1 is defined by the coverage of at least one VHF coast station offering continuous DSC alerting, typically extending about 20 to 30 nautical miles from the coast. The other sea areas are defined by MF, HF or satellite coverage rather than by VHF coverage.

Question 42GMDSS system architecture, sea areas and carriage requirements

A vessel certified to operate only in Sea area A1 must carry which minimum radio installation?

  1. An Inmarsat ship earth station and a VHF radio
  2. An HF radiotelephone with a reserve power source only
  3. An MF/HF radio installation with DSC and NBDP
  4. A VHF radio installation with DSC, plus a second means of initiating distress alerting Correct answer.

Explanation

For A1-only operation the carriage requirement is a VHF installation capable of DSC and radiotelephony, together with a means of initiating distress alerting from the position from which the ship is normally navigated. A second means of alerting is required, which may be a second VHF or another approved device.

Question 43GMDSS system architecture, sea areas and carriage requirements

Which equipment provides the primary distress alerting capability for a ship operating in Sea area A3?

  1. A VHF DSC installation only
  2. A 406 MHz EPIRB only
  3. An Inmarsat ship earth station or an MF/HF installation with DSC Correct answer.
  4. A NAVTEX receiver only

Explanation

Sea area A3 lies within the coverage of an Inmarsat geostationary satellite, so the required alerting capability is either an approved ship earth station or an MF/HF DSC installation. A VHF set alone cannot reach beyond A1, and an EPIRB is a secondary means rather than the primary installation.

Question 44GMDSS system architecture, sea areas and carriage requirements

What is the principal function of the NAVTEX system within the GMDSS?

  1. Relaying VHF distress calls to satellites
  2. Providing two-way distress alerting to rescue coordination centres
  3. Determining the ship's position for DSC alerting
  4. Broadcasting maritime safety information to ships by narrow-band direct printing Correct answer.

Explanation

NAVTEX is a terrestrial broadcast service that distributes maritime safety information such as navigational warnings and weather forecasts to ships using narrow-band direct printing on 518 kHz. It is a receive-only service and plays no part in transmitting distress alerts.

Question 45GMDSS system architecture, sea areas and carriage requirements

Which frequency band is used by the Digital Selective Calling distress alerting function on VHF?

  1. Channel 06
  2. Channel 16
  3. Channel 13
  4. Channel 70 Correct answer.

Explanation

VHF DSC alerting is carried on channel 70 at 156.525 MHz, which is reserved exclusively for digital selective calling. Channel 16 remains the radiotelephony distress and calling channel and must not be used for DSC.

Question 46GMDSS system architecture, sea areas and carriage requirements

Which document should a GMDSS radio operator consult to confirm the equipment that a particular ship must carry?

  1. The International Code of Signals
  2. The ship's stability booklet
  3. The Notice to Mariners in force
  4. The ship's Cargo Ship Safety Radio Certificate and its Record of Equipment Correct answer.

Explanation

The Safety Radio Certificate states the sea area for which the ship is certified, and the attached Record of Equipment lists the radio installations actually provided. Together they show whether the carriage requirements for the certified sea area are met.

Question 47GMDSS system architecture, sea areas and carriage requirements

Which statement best describes the role of the Rescue Coordination Centre in the GMDSS?

  1. It broadcasts routine weather forecasts to all ships
  2. It maintains the ship's radio logbook
  3. It coordinates the search and rescue response after a distress alert is received Correct answer.
  4. It assigns MMSI numbers to ships

Explanation

A Rescue Coordination Centre receives distress alerts and organises the search and rescue response, including tasking vessels and rescue units. Routine broadcasts and administrative functions such as MMSI allocation belong to other services.

Question 48GMDSS system architecture, sea areas and carriage requirements

A ship is certified for Sea areas A1, A2 and A3. Which combination of installations satisfies the minimum carriage requirement for distress alerting?

  1. VHF DSC, MF DSC and either an Inmarsat ship earth station or MF/HF DSC Correct answer.
  2. MF DSC and a NAVTEX receiver
  3. VHF DSC and an SART
  4. VHF DSC and a 406 MHz EPIRB

Explanation

A ship certified for A1, A2 and A3 must be able to alert from each of those areas, so it needs VHF DSC for A1, MF DSC for A2 and a satellite or MF/HF DSC capability for A3. A single EPIRB or a SART does not replace these primary installations.

Question 49GMDSS system architecture, sea areas and carriage requirements

Which of these is the correct definition of Sea area A2?

  1. The area within Inmarsat coverage, excluding A1 and A2
  2. The area outside all satellite coverage, including polar regions
  3. The area within VHF coverage of a coast station
  4. The area within MF coast station coverage in which continuous DSC alerting is available, excluding A1 Correct answer.

Explanation

Sea area A2 is the region, other than A1, within the radiotelephone coverage of at least one MF coast station offering continuous DSC alerting. It is therefore defined by MF coverage and excludes areas already served by VHF.

Question 50GMDSS system architecture, sea areas and carriage requirements

What is the purpose of the reserve source of energy required for GMDSS radio installations?

  1. To recharge the batteries of portable VHF radios only
  2. To drive the ship's main propulsion control system
  3. To power the ship's navigation lights during a blackout
  4. To supply the radio installation for a defined period if the main and emergency sources fail Correct answer.

Explanation

The reserve source of energy must be independent of the main and emergency generators and must be capable of supplying the radio installation for the period specified in the regulations. Its purpose is to keep distress and safety communications available after a failure of the normal supplies.