If the vessel is beyond range of NAVTEX...

🔍 Key Concepts

• GMDSS (Global Maritime Distress and Safety System) carriage requirements for receiving Maritime Safety Information (MSI) • Differences between NAVTEX, Inmarsat-C (Sat-C), and HF/MF Telex (NBDP) for MSI reception • The meaning of FEC (Forward Error Correction) vs ARQ (Automatic Repeat reQuest) in the context of MSI broadcasts

💭 Think About

• When both NAVTEX and Sat-C are unavailable, which remaining GMDSS system is intended to provide MSI at long range? • Is MSI generally transmitted as a point-to-point, two-way connection, or as a one-way broadcast that many ships can receive at once? • Look carefully at the frequencies and modes mentioned in each option: which combinations are actually used for MSI broadcasts rather than for routine two-way traffic?

✅ Before You Answer

• Verify which frequencies are standard for NAVTEX MSI and which bands are used for HF MSI broadcasts under GMDSS. • Check whether MSI broadcasts use FEC or ARQ as the primary mode, and why that is preferable for safety information. • Confirm which options describe a broadcast reception setup (no calling/handshaking) versus a two-way, addressed communication method.

If the vessel is beyond range of NAVTEX broadcasts and the Sat-C system fails, the GMDSS operator must:

Select an HF MSI frequency and FEC TELEX mode to receive MSI.

Select 518 kHz ARQ TELEX on the MF/ HF console to receive MSI.

Request repairs of the Sat-C system and wait until within range of NAVTEX.

Select 518 kHz FEC TELEX on the MF/ HF console to receive MSI.

🔍 Key Concepts

💭 Think About

✅ Before You Answer