Watchkeeping Emergencies: Man Overboard, Collision Avoidance, and Machinery Casualty

Watchkeeping Emergencies: Man Overboard, Collision Avoidance, and Machinery Casualty

A watchstander's most important quality is readiness. Emergencies at sea develop fast, and the first two minutes of your response often determine the outcome. This lesson covers the three emergencies you are most likely to face on watch: a person going overboard, a developing collision situation, and a propulsion machinery casualty. Each has a defined immediate-action sequence you must execute in order, communicate through the right channels, and record accurately in the ship's log.

Man Overboard (MOB)

When a person goes overboard, your immediate actions follow a fixed sequence that no one is permitted to skip or reorder.

Immediate actions:

1. Shout "Man overboard, [port/starboard side]" so all nearby crew hear it.

2. Throw a life ring buoy and any available floating light or smoke signal toward the person.

3. Assign one person to keep eyes on the victim continuously — do not let that lookout do anything else.

4. Note or mark the GPS position immediately.

5. Inform the officer of the watch (OOW) and sound the MOB alarm.

6. Transmit a distress message on VHF Channel 16 using the MAYDAY format if the person is in immediate danger, or a SECURITE/PAN-PAN call as the situation dictates. A typical MOB distress call begins: "MAYDAY MAYDAY MAYDAY, this is [vessel name] [vessel name] [vessel name], MMSI [number], we have a man overboard at position [lat/long], we are [description of vessel], [number] persons on board, [any other relevant information], OVER."

7. Execute the Williamson Turn or the appropriate ship-handling maneuver ordered by the master.

8. Post extra lookouts and prepare rescue equipment (rescue boat, throwing lines, Jacob's ladder).

Stand down the alarm only when the master orders it. Do not assume the person has been recovered until the OOW confirms it.

Collision Avoidance

The International Regulations for Preventing Collisions at Sea (COLREGs) govern every vessel at all times. On watch, your job is to detect a developing close-quarters situation early and act decisively.

Key COLREGs concepts for watchstanders:

• A vessel is considered to be in a close-quarters situation when the risk of collision cannot be excluded without drastic action.
• Rule 16 (give-way vessel) requires early and substantial action; Rule 17 (stand-on vessel) requires maintaining course and speed until the give-way vessel fails to act.
• Rule 8 requires that any action to avoid collision be large enough to be readily apparent to the other vessel, taken in ample time.

Immediate actions when collision risk develops:

1. Increase the frequency of radar/visual bearings. A steady compass bearing to an approaching vessel confirms collision risk.

2. Alert the OOW immediately.

3. Sound the appropriate sound signal (five or more short blasts = danger/doubt signal).

4. Take helm and/or engine action as directed or as authorized by standing orders.

5. Make an urgent call on VHF Channel 16 or the agreed working channel to the other vessel if identity is known.

6. Record all observations, bearings, and actions in the deck log with accurate times.

If the master has not reached the bridge and collision is imminent, the OOW has the authority and the duty to take whatever action is necessary to avoid collision.

Propulsion Machinery Casualty

A main engine shutdown alarm or unexpected loss of propulsion while maneuvering can put a vessel in immediate danger. Engine room watchstanders and deck watchstanders must communicate instantly.

Engine room immediate actions (loss of propulsion):

1. Acknowledge the alarm and identify the cause (fuel, cooling water, lube oil, electrical fault).

2. Notify the chief engineer and the bridge immediately using the engine room telegraph or phone, reporting: nature of alarm, current engine status, and estimated time to restore propulsion (if known).

3. Follow the engine room standing orders and the emergency procedures card for the specific casualty.

4. Do not attempt to restart the engine against a safety shutdown without authorization from the chief engineer.

5. If fire or flooding is involved, shift to the relevant emergency procedure and activate appropriate alarms.

Bridge immediate actions on losing propulsion:

1. Ring "Stop" on the telegraph and confirm with the engine room.

2. Notify the master immediately.

3. Assess the vessel's position, drift, and proximity to hazards.

4. Consider anchoring if in shallow water.

5. Broadcast a SECURITE or PAN-PAN on VHF Channel 16 if the vessel is a hazard to navigation.

6. Log all times, alarms, communications, and actions.

Logging Emergency Events

Every emergency must be recorded in the official ship's log as soon as the immediate danger is controlled. A proper log entry contains:

• Time of the event (UTC or ship's time, clearly labeled)
• Nature of the casualty (brief, factual description)
• Actions taken (in sequence, who did what)
• Personnel notified (OOW, master, chief engineer, Coast Guard, etc.)
• Outcome (person recovered, collision avoided, propulsion restored, etc.)

Log entries are legal documents. Write in plain language, use exact times, and never alter an entry after the fact.

Safety Points

• Always wear or have a PFD immediately accessible during dockside or vessel drills.
• Never lean over the rail to look for a MOB without securing yourself.
• In any machinery space during a casualty, follow lockout/tagout procedures before touching any isolated equipment.
• If you are unsure of any immediate action, call the OOW or chief engineer — notification is never wrong.

Practice drills make these sequences automatic. The scenarios you run today are the foundation for the STCW Basic Training and USCG credentialing standards that follow you throughout your career.