Distress Alert with an Inverted Latitude
At 0312 UTC, the 12,000 GT bulk carrier MV Kestrel is in Sea Area A2 in the Gulf of Alaska, 90 nm south of Kodiak. A fire has broken out in the engine room; main power is lost, and the emergency generator is carrying the radio installation. The master orders a DSC distress alert on 2187.5 kHz. The operator selects distress, nature "fire", but in haste keys the position as 56°12.0′S 148°30.0′W instead of 56°12.0′N. The DSC set displays "distress alert transmitted", and no acknowledgment arrives within five minutes. The operator then transmits a MAYDAY on VHF channel 16 giving the correct latitude, and a nearby tanker replies that its DSC log shows a South Pacific position. The vessel carries a float-free 406 MHz EPIRB with GNSS, two SARTs, and three portable VHF radios. The fire is not under control, and the crew is mustering at the lifeboat stations. The master asks whether to activate the EPIRB and whether a second DSC alert is appropriate.
1. What should the operator do about the incorrect position in the DSC distress alert, and why?
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A real distress exists, so the alert must not be cancelled as a false alert. Position is a primary search datum: an inverted latitude puts the reported casualty in the South Pacific, thousands of nautical miles from the Gulf of Alaska, and SAR assets could be dispatched to the wrong area.
The operator should send a second DSC distress alert with the corrected position, using the distress-alert update or repeat function if the equipment provides it. Immediately afterward, transmit a short MAYDAY on channel 16 that explicitly corrects the earlier alert: name, call sign, MMSI, corrected position 56°12.0′N 148°30.0′W, nature of distress, and assistance required. The operator should also answer the tanker and ask it to pass the correction to the coast station.
Repeating the alert is justified because the error is material, not a minor formatting issue. A distress cancellation would be wrong because the fire is real. Log the original alert time, the corrected alert, the voice correction, and all acknowledgments.
2. Should the EPIRB be activated now? Explain the decision.
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The EPIRB should be activated when the master decides that abandonment is imminent or that the fire is uncontrollable, not merely because the DSC alert had a position error. The decision turns on the immediate danger to the crew, not on the radio mistake.
If activated, the 406 MHz EPIRB with GNSS provides an independent alert and an accurate position to COSPAS-SARSAT, which is valuable here because the DSC position is wrong. It should remain on, be taken to the survival craft if the crew abandons, and the RCC should be told by radiotelephony that the EPIRB has been activated. Activating it prematurely while the fire is being controlled could generate an unnecessary SAR response, but with the fire not under control and the crew mustering, manual activation on the master's order is appropriate. The EPIRB should not be switched off once activated unless the RCC directs it or the emergency is resolved and the RCC is informed.
3. What radiotelephony sequence should the vessel use, and how should it handle the tanker's request for clarification?
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The distress call and message should follow the standard sequence: MAYDAY, MAYDAY, MAYDAY; THIS IS Kestrel, call sign, MMSI; position 56°12.0′N 148°30.0′W; nature of distress, fire in the engine room; assistance required; number of persons on board; and any other useful information such as course, speed, and whether the vessel is abandoning.
The operator should then correct the record explicitly: 'My previous DSC distress alert gave an incorrect latitude; correct position is 56°12.0′N 148°30.0′W.' When the tanker asks for clarification, the operator should confirm the correction concisely and ask the tanker to relay the corrected position to the coast station if it has not established contact. Distress traffic has absolute priority, so routine chatter on channel 16 must stop. Once a coast station or RCC responds, the vessel should follow its instructions, shift to a working frequency such as 4125 kHz if directed, and keep a continuous listening watch.