As master of a 300 GT near-coastal cargo vessel you are about to load. Your stability booklet shows the calculated GM at the proposed loading condition is 0.22m. Your examiner asks whether this is acceptable.

A. IS CODE 2008 (International Code on Intact Stability) — criteria for cargo ships: the IS Code provides mandatory stability criteria for vessels under the 2008 International Code on Intact Stability (made mandatory under SOLAS II-1 and Load Lines). Minimum criteria: (1) AREA under GZ curve from 0° to 30° must be not less than 0.055 metre-radians; (2) Area from 0° to 40° (or flooding angle, whichever is less) not less than 0.09 metre-radians; (3) Area between 30° and 40° (or flooding angle) not less than 0.03 metre-radians; (4) GZ at 30° or greater must be not less than 0.20m; (5) Maximum GZ must occur at an angle of heel not less than 25°; (6) Initial GM (GM_0) must not be less than 0.15m. In this scenario: GM of 0.22m exceeds the minimum 0.15m — it satisfies this criterion. HOWEVER: GM alone does not determine acceptability — you must check ALL the criteria listed above (particularly the GZ curve at 30° and the area criteria). A vessel can have a positive GM but still fail the area criteria if the GZ curve drops too early. The stability booklet must be consulted to verify the full GZ curve for the proposed loading condition.

B. A GM of 0.22m is inadequate — the minimum for any vessel is 0.30m. Loading in this condition is not permitted under MCA regulations.

C. GM is the only stability criterion — a positive GM of any magnitude above zero is sufficient for a vessel to be considered stable and safe to sail.

D. The 0.22m GM is acceptable for a near-coastal voyage but would not meet the standards for an ocean passage. Near-coastal vessels have lower stability requirements.

A. ANGLE OF LOLL: this is the classic presentation of negative GM (unstable equilibrium). Cause: the vessel's metacentric height (GM) has become negative — the metacentre (M) is now BELOW the centre of gravity (G). At 0° upright, the vessel has no restoring moment — but as she heels, the waterplane area shifts, moving B outward until a point of neutral equilibrium is found: this is the angle of loll (typically 5°-20°). The vessel "rests" here rather than returning upright. Common causes on a small coastal vessel: (1) Free surface effect from flooded compartments, slack tanks, or water in bilges; (2) Topside icing (raised G); (3) Cargo shift or absorption of water by deck cargo (timber); (4) Consumption of fuel and water from the bottom of tanks without compensating. IDENTIFICATION test: if you push the vessel toward the loll (to starboard) she returns to the loll angle; if you force her past the loll, the GZ curve at higher angles may generate restoring force — she "snaps" back to the loll. EMERGENCY ACTIONS: (1) DO NOT immediately ballast the high side (port) — if she rolls through the loll onto the other side, she may capsize; (2) Check and pump out bilges; (3) Fill double bottom ballast tanks SLOWLY starting with those on the LOW side (starboard) to raise M; (4) Reduce topweight; (5) Call master (if OOW); (6) Alert crew and consider reducing speed.

B. An 8° list to starboard means a weight has shifted to starboard — immediately correct by ballasting the port side to bring her upright, then investigate the cause.

C. A list that stays fixed at 8° is a permanent heel caused by off-centre loading. Correct it by shifting cargo from the starboard side to port before continuing.

D. A vessel that doesn't return from a list has insufficient GM. Calculate a righting lever at 8° using the GZ curve and if positive, the vessel is stable enough to continue.

A. PYROTECHNIC DISTRESS SIGNALS — requirements under SOLAS III Regulation 6 for small cargo vessels: Typical requirement for a near-coastal cargo vessel (MCA may specify by category — refer to MGN 280(M) and the vessel's LSA list): (1) RED PARACHUTE ROCKETS: sent up high (minimum 300m), burns for at least 40 seconds, seen at long range. Use: day or night in DISTRESS — when position is uncertain and assistance is needed; visible from greatest distance; (2) RED HAND FLARES: lower altitude, held in hand. Use: when rescue vessel is in the vicinity and you need to mark your exact position; burns for at least 1 minute; (3) ORANGE SMOKE SIGNALS: floating or hand-held orange smoke. Use: DAYTIME only when rescue is close; highly visible to aircraft during daylight; no use at night; burns/emits for at least 3 minutes. TYPICAL MINIMUM REQUIREMENT for a near-coastal cargo vessel: 4 red parachute rockets + 4 red hand flares + 2 orange buoyant smoke signals (carried in the emergency bag/liferaft pack). EXPIRY: all pyrotechnics expire (typically 3 years from manufacture) — expired signals may be retained for training but do NOT count toward the statutory requirement. USE IN DISTRESS: Rule 37 and Annex IV COLREGs lists pyrotechnic signals as approved distress signals.

B. Near-coastal vessels under 200 GT are not required to carry pyrotechnic signals. An orange smoke flare is sufficient for all distress situations.

C. Red parachute rockets are for use in harbour approaches only. At sea, white rockets should be used to signal distress to attract the attention of merchant vessels.

D. Expired pyrotechnics can continue to be counted toward the statutory requirement for 6 months after their expiry date, provided they are stored correctly.