M500-2.1.2

Action following collision, grounding, heavy weather damage and water ingress

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What the Examiner Is Really Probing

This outcome tests whether you think and act as the person in command — not as someone who reacts to events, but as someone who controls the response. A pass-standard answer demonstrates a clear mental model: assess, contain, communicate, and decide. The examiner wants to hear command language, not a checklist recited from memory.


Underlying Knowledge

Immediate Priorities — Any Damage Scenario

Your first three questions, in order:

  1. Are people safe? Account for all crew and any passengers. Are there casualties requiring immediate action?
  2. Is the vessel in immediate danger of sinking or loss of control? Stabilise the situation before anything else.
  3. Is the situation deteriorating or stable? This drives every decision that follows.

Collision

  • Stop engines if immediate risk of further flooding through propeller wash or dragging the casualty.
  • Do not back off immediately — the other vessel's hull may be acting as a plug. Assess before manoeuvring.
  • Sound alarm; muster crew; close watertight doors and openings.
  • Assess your vessel: bilge soundings, visual inspection of compartments, damage control party assigned.
  • Assess the other vessel: your duty to render assistance (SOLAS V/33) is a master's legal obligation. Render assistance so far as you can do so without serious danger to your vessel and those on board.
  • Transmit DSC Distress or Urgency as situation demands; notify flag state and port authority.
  • Do not move the vessel until you have a clear picture — or until remaining will cause greater danger.
  • Record everything: times, actions, weather, positions.

Grounding

  • Stop engines; assess whether propeller is fouled or tunnel flooded.
  • Do not immediately attempt to refloat — first determine whether the vessel is holed. Refloating a holed vessel in deep water can sink her.
  • Bilge soundings and visual inspection of all compartments.
  • Note state of tide and whether tide is rising or falling — this is critical to your decision on whether to wait or act.
  • Consider: What is the seabed type? Is the vessel pounding? Is weather worsening?
  • Calculate whether lightening ship (fuel, water, stores) aids refloating without increasing danger.
  • Mayday or Pan-Pan as appropriate; notify coast guard, owner, flag state.
  • If attempting to refloat: lay out an anchor to prevent the vessel going further aground.

Heavy Weather Damage and Water Ingress

  • Locate the source: collision damage, failed stern gland, sea cock failure, porthole or hatch breach.
  • Pumping is a management tool, not a solution — find and plug the source.
  • Use available damage control materials: soft wood plugs, collision mat, hull foam, shaped timber.
  • Reduce the vessel's motion if ingress is through deck openings — alter course or reduce speed.
  • Redistribute crew weight and ballast to keep the damaged area as high as possible.
  • Monitor bilge levels continuously; if rising faster than pumps can manage, escalate immediately to distress.
  • Watertight integrity: close all non-essential sea cocks; check all through-hull fittings.

How to Structure Your Spoken Answer

Open with the command stance: "My immediate priority is the safety of those on board and the vessel." Then walk through assess–contain–communicate–decide. Give the examiner a logical sequence, not a list of bullet points. Show that you are making decisions, not just executing procedures. Quantify where you can — state of tide, bilge levels, pump capacity — to demonstrate technical grip. Always bring the answer back to your legal obligations: render assistance, report to the appropriate authority, maintain the log.

Practice questions

oralcore

You are underway at night and strike an uncharted object. The vessel is making water. Walk me through your response.

scenariocore

You have gone aground on a falling tide. Your bilges are dry. What governs your decision on whether to attempt immediate refloating?

recallcore

What is your legal duty when your vessel is involved in a collision with another vessel?

scenariostretch

Water ingress is being managed by the bilge pumps, but your engineer tells you the level is rising slowly despite the pumps running continuously. What is your decision point for transmitting a Mayday?

scenariostretch

You have suffered heavy weather damage and a porthole has been stove in forward. Water is coming in heavily. What practical damage control measures do you take while assessing whether to transmit a distress?

Independent preparatory study aligned to the MCA Master (Yachts less than 500 GT) oral examination syllabus. Not an MCA-approved course and confers no credit toward a Certificate of Competency.