Stability oral questions
Example questions on stability, watertight integrity and heavy weather, set against the syllabus items they come from. They are our wording, not the MCA's — use them to find the gaps, then answer them out loud with your own vessel in mind.
No — they are our examples. The MCA publishes the syllabus for each oral, and every set below is our own wording of how one of its stability or seaworthiness items can be asked. The syllabuses on GOV.UK are the authority; check yours for the full list.
OOW (Yachts <3000 GT), section 3.2, Seaworthiness of the Ship: watertight integrity, preparing for heavy weather, and the effect on stability of raising and lowering weights, low freeboard, obstructed freeing arrangements and scuppers, and slack tanks.
Master (Code vessels <200 GT) / OOW (Yachts <500 GT), section 2.5: the same items, plus 'the difference between good stability and poor stability' and the warning signs of poor stability.
Master (Yachts <500 GT): section 3.2 (heavy weather, watertight integrity, dry-docking and a 'working knowledge of stability and trim information'), with partial loss of intact buoyancy at 2.2. Master (Yachts <3000 GT): section 3.2 (watertight integrity, load line items affecting seaworthiness, ingress of water, dry-docking) and 2.1, the effect of flooding a compartment on trim and stability.
Chief Mate and Master (Yachts Unlimited): the competence 'Control trim, stability and stress'. The Master syllabus adds stiff and tender conditions, large angles of heel, excessive trim, free surface and the angle of loll.
For merchant officers, MIN 653 Amendment 1 section 3 (OOW Unlimited) lists the stability terms to explain, among them the effect on G of loading and moving weights, list and loll, free surface and GZ curves.
Out loud, and about your own vessel where the question allows it — the MIN 653 OOW Unlimited syllabus names 'own vessel's state of stability' as an item. Where a sketch would help, practise drawing it as you talk.
“What is the difference between good and poor stability? What signs would tell you the yacht's stability is poor?”
“What happens to the centre of gravity when you load, discharge or move a weight?”
“Sketch a GZ curve. What does it tell you, and where do you find the one for your vessel?”
“What is the difference between a list and an angle of loll? How would you correct each?”
“What are the IMO intact stability criteria, and how do you know you meet them?”
“What is free surface effect, and why is it dangerous at small angles of heel?”
“How do tank subdivision and the density of the liquid change free surface effect?”
“What do 'stiff' and 'tender' mean? How would each feel in a seaway?”
“What would you do with a large angle of heel or list before you knew its cause?”
“How does stability change during a voyage as fuel and water are used?”
“You're about to launch the tender with the deck crane. What stability checks do you make before you lift?”
“Why do slack tanks matter? How would you manage tanks on passage?”
“What does low freeboard do to stability?”
“Deck gear has been stowed across the freeing ports. Why is that a stability problem?”
“Where is the stability and trim information for your yacht, and what is in it?”
“How does ballasting affect stability and hull stress?”
“Guests and crew gather on the upper deck for an event. Does it matter for stability?”
“You're taking on fuel and fresh water before a passage. How do you plan the order of filling?”
“Heavy weather is forecast for tomorrow. What do you do today?”
“Which openings matter for watertight integrity on your yacht, and who checks they are closed?”
“How are watertight doors, side scuttles and scuppers operated, maintained and tested?”
“Which load line items affect seaworthiness?”
“How do you prepare the vessel for sea before sailing?”
“How would you manage a small ship in heavy weather?”
“Your vessel is disabled in a rising sea. How do you handle her?”
“What can heavy weather do to the ship's structure?”
“After a collision a compartment is flooding. What happens to trim and stability, and what do you do?”
“What is down-flooding? Which large openings on a yacht create the risk?”
“What does partial loss of intact buoyancy mean, and what are your first actions?”
“Water is coming into the hull and you don't know where from. Talk me through your response.”
“How do you prepare the vessel for dry-docking? What changes if she is damaged?”
“You've put in to a port with hull damage. What do you need to think about before you sail again?”
The notices change. Always check the current version on GOV.UK before you apply or book.
Study and Logbook are both live on the App Store. Open either to get started.
