Question 61 ONC01 - Master/Chief Mate Unlimited Tonnage

The Correct Answer is B **Explanation of Correct Option (B):** When a false distress alert has been inadvertently sent via VHF radio, the regulatory requirement (specifically under the GMDSS regulations) is to immediately cancel the alert to prevent search and rescue (SAR) resources from being deployed unnecessarily. This cancellation must be broadcast to all stations in the area. The mandatory frequency for initiating all distress, urgency, and safety communications, and monitoring general marine communication traffic, is **VHF Channel 16 (156.8 MHz)**. The proper procedure involves: 1. Switching the radio to Channel 16. 2. Announcing "All Stations, All Stations, All Stations." 3. Stating the ship's name and call sign. 4. Stating "Cancel my distress alert of [time] [date] [position]." 5. Giving a brief reason for the accidental transmission. 6. Ending with "Out." This ensures the cancellation message is received immediately by the Coast Guard and any vessels monitoring the distress channel. **Explanation of Incorrect Options:** * **A) Send a DSC cancellation message on Ch-70:** While the initial false alert might have been sent via DSC on Channel 70, the standard, universally recognized, and mandatory procedure for broadcasting a cancellation message to the wider maritime community and coordinating authority (Coast Guard) is a voice announcement on Channel 16. DSC is primarily used for the initial alert or selective calling, not for generalized cancellation broadcasts. * **C) Make a voice announcement to cancel the alert on Ch-22A:** Channel 22A (often referred to as just 22 or 22A in US waters) is typically a working channel designated by the Coast Guard for communications with vessels after initial contact has been made on Channel 16 (or an alert received). It is not the designated channel for broadcasting an emergency cancellation announcement to all stations. * **D) Make a voice announcement to cancel the alert on Ch-13:** Channel 13 is designated primarily for Bridge-to-Bridge navigation communications, especially concerning maneuvering, passing, and meeting in confined waters or near ports. It is generally restricted to low power (1 watt) and is not the correct channel for broadcasting general distress or cancellation information to all stations.