In dense fog, what does a signal of one prolonged blast followed by three short blasts indicate?

In dense fog, what does a signal of one prolonged blast followed by three short blasts indicate?

• A. Vessel not under command
• B. Vessel engaged in fishing
• C. Vessel restricted in its ability to maneuver
• D. Manned vessel being towed

Answer: (D)

In dense fog, ships use specific sound patterns to quickly convey their status to others. One prolonged blast followed by three short blasts is the signal for a vessel being towed. This tells nearby vessels that the observed ship cannot maneuver on its own and is moving under tow, so others should take extra care and give way as needed. The other listed conditions have different fog-signal patterns, so they don’t match this sequence.

In dense fog, ships use specific sound patterns to quickly convey their status to others. One prolonged blast followed by three short blasts is the signal for a vessel being towed. This tells nearby vessels that the observed ship cannot maneuver on its own and is moving under tow, so others should take extra care and give way as needed. The other listed conditions have different fog-signal patterns, so they don’t match this sequence.