Question 5A1

GMDSS regulations mandate that all vessels, regardless of the sea area they operate in, must be able to transmit distress alerts to shore. For a vessel remaining in Sea Area A1 (within VHF DSC coverage of a coast station), the primary means of distress alerting is VHF DSC. However, GMDSS also requires at least two independent means of transmitting distress alerts to shore. Typically, this secondary means is a 406 MHz EPIRB. Both the VHF DSC and the EPIRB are "radio installations capable of initiating the transmission of ship-to-shore distress alerts." Therefore, statement A correctly reflects a fundamental GMDSS requirement for any equipped vessel. Here's why the other options are incorrect: * **B) VHF DSC alerting may be the sole means of Distress alerting.** This is false. GMDSS requires multiple, independent means of distress alerting to shore to ensure redundancy and reliability. * **C) HF or MF DSC may satisfy the equipment requirement.** This is incorrect. HF and MF DSC are primarily required for Sea Areas A2, A3, and A4, which are beyond the range of VHF DSC. While an A1 vessel *could* have them, they are not the primary or mandated equipment for Sea Area A1. * **D) HF SSB with 2182 kHz automatic alarm generator may satisfy the equipment requirement.** This is incorrect. 2182 kHz is the MF radiotelephony distress frequency, and the automatic alarm generator is a legacy alert method. GMDSS primarily uses Digital Selective Calling (DSC) for automated alerting. HF SSB is generally for longer range communication in Sea Areas A3 and A4.