FCC GMDSS Maintainer study plan

Map the GMDSS sea areas A1–A4 to the carriage requirements each area imposes, listing for each area the mandatory DSC, radiotelephony, NBDP, satellite, EPIRB and SART equipment.

Explain the functional requirements of the GMDSS (alerting, SAR coordination, locating, MSI, general radiocommunication, bridge-to-bridge) and name the equipment that satisfies each function.

Describe the DSC message structure end to end: format specifier, self-identification (MMSI) field, category, nature of distress, position/time, communication mode and the check-sum/EOS sequence, and identify where each field sits in a type-approved unit.

Decode the MMSI numbering scheme, distinguishing ship station, coast station, group, SAR aircraft and hand-held VHF identities, and state which digit patterns are reserved.

Trace the role of the Rescue Coordination Centre, the ship earth station and the coast radio station in a distress alert and its acknowledgement, noting which links use DSC and which use Inmarsat.

Operate a DSC controller through the routine, safety, urgency and distress call sequences, including correct use of the distress button cover, the distress alarm reset and the 5-second transmission guard.

Explain distress relay, distress priority acknowledgement, and the conditions under which a coast station or another ship must relay an alert.

Describe the DSC watchkeeping frequencies for VHF channel 70, MF 2187.5 kHz and HF 8414.5 kHz plus the additional HF distress frequencies, and state the purpose of each.

Identify common DSC equipment faults (no GPS input, incorrect MMSI, failed self-test, antenna VSWR alarm, printer or interface failure) and describe the first diagnostic step for each.

Distinguish DSC test calls from routine calls and state when a test call to a coast station is appropriate.

Recite the distress, urgency and safety priority definitions and the correct use and pronunciation of MAYDAY, PAN PAN and SÉCURITÉ, including the relay and silence procedures.

Compose a full distress message with position, nature of distress, assistance required and other information, and adapt it for a vessel with DSC-then-voice and Inmarsat alerting paths.

Describe the radiotelephony distress frequencies (VHF 16, MF 2182 kHz, HF 4125/6215/8291/12290/16420 kHz) and the purpose of the HF paired channels used for SAR coordination.

Explain NBDP (telex-over-radio) operation: ARQ, FEC and the selective calling procedure, and state how NBDP is used for distress traffic on HF.

Describe on-scene communications, including SAR co-ordinator and on-scene co-ordinator roles, the use of SART and AIS-SART responses, and the bridge-to-bridge channel conventions.

Explain Inmarsat system architecture: space segment, land earth stations, Network Coordination Station, and the maritime, aeronautical and land mobile services.

Describe the Inmarsat-C distress alerting path, including the distress priority setting, the acknowledgement from the LES and the role of the Rescue Coordination Centre.

Compare Fleet (FleetBroadband/Fleet One) and Inmarsat-C for distress, urgency, safety and routine traffic, and state which services are mandatory in which sea areas.

Describe the Maritime Safety Information broadcast path over SafetyNET and SafetyCast, including the enhanced group call addressing for fixed areas and for circular areas around a distress position.

Explain how to test and verify an Inmarsat terminal's distress path, including the use of test messages and the checks a maintainer performs on the distress button wiring and the GPS feed.

Describe the 406 MHz COSPAS-SARSAT system: beacon types, the TAC and the beacon registration database, and the difference between 121.5 MHz homing and 406 MHz alerting.

Explain the SART: X-band radar response pattern, range, battery shelf life and operational test procedure, and the AIS-SART alternative.

Describe the NAVTEX system: 518 kHz international, 490 kHz national and 4209.5 kHz, the B1/B2/B3/B4 transmitter and message-type designations, and the effect of range and time-sharing.

Explain the MSI broadcast structure: NAVAREA/METAREA coordination, the roles of the NAVTEX coordinator and the SafetyNET provider, and the message types a ship must receive.

Identify typical EPIRB and SART faults (battery expiry, self-test failure, water-activated switch, mounting and hydrostatic release, antenna connection) and the checks used to isolate each.

Describe the ship's battery installation: lead-acid versus VRLA versus lithium, capacity rating and the effect of discharge rate, and the calculation of required reserve capacity for the GMDSS radio battery.

Explain charging regimes (float, boost, temperature compensation) and the specific gravity and voltage measurements used to assess battery condition.

Describe the GMDSS antenna system: VHF, MF/HF whip and long-wire, Inmarsat, GPS, EPIRB and SART antennas, and the importance of VSWR, grounding and lightning protection.

Explain the power supply arrangement for GMDSS equipment, including the emergency source, the dedicated radio battery, changeover arrangements and the requirement for independence from the main machinery.

Apply a structured fault-finding method to a no-transmit fault: power, antenna, VSWR, control head, interface and configuration, in that order, and describe the test equipment used.

Describe the installation requirements for GMDSS equipment: location, mounting height, antenna separation, cable routing, labelling and the documentation that must be retained on board.

Explain the periodic and annual testing regime: daily, weekly, monthly and annual checks, the role of the shore-based maintenance provider and the record-keeping in the radio log.

Interpret a VSWR measurement and a battery load test result against acceptance criteria, and state the action to take when a result is out of tolerance.

Describe the survey and certification framework: the Safety Radio Certificate, the Cargo Ship Safety Equipment Certificate, and the role of the recognised organisation.

Diagnose a DSC position-input fault by tracing the GPS data path from receiver to controller, including the NMEA sentence and the interface settings.

Complete a timed full-length practice exam under exam conditions and score it against the domain weightings.

Review every missed or uncertain item and classify each as a knowledge gap, a procedure error or a misread question.

Re-derive the sea-area equipment matrix, the DSC message field map and the distress message sequence from memory without notes.

Explain to a colleague, in plain language, the distress path for each of the four sea areas, including which equipment is used and why.

Confirm the regulatory references you will rely on (SOLAS IV, ITU Radio Regulations, IMO resolutions) and note the ones you still need to read.