M3000-3.2.3

Action on ingress of water into the hull

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Candidates consistently give a reactive, engineering-led answer to this topic — they describe pumping arrangements and counterflooding without first establishing the Master's command framework: assess, communicate, stabilise, decide. An examiner wants to see the Master thinking, not just the mate pulling pump handles.

The core failure mode to avoid

Telling the examiner you would 'start the bilge pumps and call the engineer' is a watchkeeper's answer. As Master you must own the situation from the moment you are informed. Your decisions determine whether the vessel survives or is abandoned, and those decisions carry legal weight.

Immediate actions — what the Master does

  • Establish the source, rate of ingress, and location relative to watertight subdivisions. You cannot manage what you have not measured.
  • Post a continuous watch on the bilge level and insist on timed readings so you can plot the rate of rise — is the situation stable, improving, or deteriorating?
  • Assess reserve buoyancy and stability. Flooding in a free-surface condition attacks GM before freeboard. A yacht with tanks or open compartments partially filled can lose stability before she visibly settles.
  • Alert the crew: damage control stations, not panic. Brief, calm, task-specific orders.
  • Transmit a DSC Urgency (PAN PAN) or Distress (MAYDAY) call as appropriate, at the earliest moment the situation warrants it. SOLAS V/33 duty to render assistance is a two-way obligation — the Coast Guard cannot help you if they do not know. Early communication preserves options; late communication forecloses them.
  • Notify the owner/company DPA if ISM applies, and the nearest coastal state authority depending on flag state requirements.

Damage control measures

  • Internal: bilge pumps (fixed system and portable), damage control plugs, shores, collision mats, cement boxes, wooden wedges. The crew must know where damage control equipment is stowed — if the locker has not been opened since the last port, that is a command failure.
  • External: where the ingress is accessible from outside and conditions allow, a collision mat or fothering reduces the head driving water in.
  • Progressive flooding: close watertight doors and ventilation penetrations to contain the casualty to one compartment. Do not flood an intact compartment to correct list unless you have calculated the effect on stability — counterflooding a yacht is high-risk and rarely the correct first move.

The decision to abandon

If the rate of ingress exceeds pumping capacity and the trend is deteriorating, the Master must not delay the abandon ship order to preserve the vessel. The decision belongs to the Master alone. Issue the Mayday, activate EPIRB, deploy liferaft upwind/upcurrent of the vessel, account for all persons.

Records and post-incident

Log all actions, times, and decisions in the Official Log Book. If the vessel survives, a Class/flag state survey is required before returning to service if structural damage is suspected.

Practice questions

oralcore

Your engineer calls the bridge at 0200 to report unexplained water in the engine room bilge. The automatic bilge pump has been running for twenty minutes. What do you do?

recallcore

Why is free-surface effect a particular concern when managing flooding on a yacht?

scenariocore

You are 80 miles offshore. You identify a below-waterline hull fitting has failed and the cockpit locker is filling. The bilge pump is coping for now but the fitting cannot be reached internally. What are your options and how do you prioritise?

scenariostretch

A crew member suggests counterflooding the starboard tank to correct the list caused by flooding in the port engine room. How do you respond?

recallcore

What records must the Master make when dealing with a flooding incident?

Independent preparatory study aligned to the MCA Master (Yachts less than 3000 GT) examination syllabus (updated June 2026). Not an MCA-approved course and confers no credit toward a Certificate of Competency.