Collision at night: flooding, injured crew, oil sheen and a decision on the passage
MV Cape Meridian, a 32,000 dwt bulk carrier on ballast passage, is in position 46°10′N 038°20′W at 0240 in NW force 7 with a 4 m swell. A trawler on a crossing course strikes the starboard side at No.2 hold at the waterline; she remains visible with lights on two cables away. No.2 hold was empty and the sounding shows 2.6 m of water in a hold 20 m long and 12 m wide. Two crew are injured, one with a suspected fractured pelvis from a falling securing bar. There is a sheen of diesel from a breached double-bottom tank. Displacement after flooding is about 9,384 t, KM 7.42 m and KG 6.90 m; the loading computer shows a free surface moment for the floodwater of 2,950 t·m. The vessel has a 4° list to starboard and is trimming by the head. The nearest port, Aldenham, is 320 NM to the east.
1. Set out the bridge actions for the first fifteen minutes, including the distress alert content.
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Sound the general alarm, muster and head-count, and call the master. Bring the bridge team to full manoeuvring stations; tell the engine room to stand by and be ready for immediate manoeuvre. Close all watertight doors and vents, and check the bulkheads bounding No.2 hold, the adjacent spaces and the double bottoms with soundings and ullages. Fix the position, note the time, and plot the trawler. Check for fire and for further injuries, and get the injured men to the ship's hospital with the medical chest and a stretcher party.
Distress: transmit a DSC alert on VHF channel 70, then a MAYDAY on channel 16-MAYDAY three times, this is Cape Meridian, call sign, position 46°10′N 038°20′W, collision and flooding of No.2 hold, 4° list, two injured, require immediate assistance and medical advice, 22 persons on board. Send a copy to an RCC by Inmarsat or HF, and use the DSC or radiotelephone to alert other shipping. Do not activate the EPIRB or SART unless abandoning ship. Keep the ship's position and status updated, and tell the trawler you are standing by and will render assistance.
2. Calculate the effective GM and decide what to do about the passage, giving the reasoning.
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Solid GM = KM − KG = 7.42 − 6.90 = 0.52 m.
Free surface correction = FSM ÷ displacement = 2,950 ÷ 9,384 = 0.31 m.
Effective GM = 0.52 − 0.31 = 0.21 m.
That is above the 0.15 m IS Code minimum, but only just. The 4° list, the trim by the head, the 4 m swell and the possibility of progressive flooding all reduce the effective righting energy: the GZ curve's maximum and its range are reduced, and the list eats margin at the small angles where the ship actually works. The flooding is also a live process, not a fixed condition.
Action: pump No.2 hold. This removes both weight and free surface and improves GM; but the free surface only disappears when the hold is empty or completely full, so monitor the effect after each sounding. Press up empty double-bottom tanks on the centreline to remove their free surfaces and lower G. Keep the list within a few degrees and check it every 15 minutes. Do not continue the ocean passage: head for Aldenham at reduced speed, 320 NM at 7 kn is about two days, so shelter can be reached before the next system. Only consider beaching if flooding becomes progressive, cannot be contained and a suitable shore is available-and then with the crew prepared to abandon.
3. What are your pollution and reporting obligations, and what do you owe the trawler?
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The diesel sheen is oil. Under MARPOL Annex I any discharge of oil is prohibited except under the narrow conditions of the regulations, and a visible sheen is a reportable incident. Actions: stop or contain the leak if it can be done safely, do not wash down the deck, record the time, position and estimated quantity, and make an entry in the Oil Record Book Part I describing the casualty and the resulting discharge. Prepare a SOPEP report in the standard format and notify the company, the P&I club, the flag state and the nearest coastal state without delay, giving the position, nature and quantity of the oil, weather and the assistance required. Keep all records; they will be used in the casualty investigation.
For the trawler: SOLAS V/33 and UNCLOS Article 98 oblige the master to proceed to the assistance of persons in danger at sea and to render assistance, so far as it can be done without serious danger to his own ship and crew. Ask what she needs, stand by, and offer pumps, medical help or a tow, and only leave if told to by a competent authority or if the continuation is genuinely unreasonable. Record her name, port, damage and the exchange of messages. Report the collision to the flag and coastal states; a collision is also a reportable casualty.