Preliminary report says both bridges failed before a steel carrier sank in 11 minutes

A Turkish bulk carrier sank in about 11 minutes after a collision in the Sea of Marmara off Silivri in the early hours of 2 September. The Tuğberk İmamoğlu, owned by Zeybe Denizcilik and bound from Iskenderun to Karadeniz Ereğli with 4,199 tons of coiled steel, had 10 Turkish crew including the master. None have been found. Transport Minister Abdulkadir Uraloğlu said the sinking was rapid and that "no one has been found alive." A lifeboat and debris came up. Mobile phones on board went unanswered.

The other ship, the chemical tanker Alsu, owned by Ozpulathane Deniz Tasimaciligi and bound for Aliaga with about 3,000 tons of engine oil, reported the collision and stayed afloat with scrapes on the starboard side. Nine of her crew were detained. The Istanbul governor's office put the time at about 03:00. The maritime authority said an emergency signal left the Tuğberk İmamoğlu at 03:26 and that Alsu's master called at 03:41 to say he had hit an unidentified ship around 03:15. The first rescue craft arrived at 04:10. Helicopters and more than a dozen coastguard and rescue ships searched water 800 to 900 metres deep.

A preliminary inquiry circulated on 3 September is more useful than the first statements. It says the Tuğberk İmamoğlu was sailing as a "ghost ship": its AIS was off, broken, or not painting correctly. In the last half-mile it turned to starboard, against a radio agreement to pass to port, and cut across Alsu's bow. That turn, the report says, was the operational act that started the collision. The deeper failure, it says, was on Alsu. The master was asleep in his cabin. A single officer was on his first watch on that ship. No lookout was posted, against the tanker's own watch condition B. The officer saw the other ship late, at about 0.5 nautical miles, after it flickered off and back onto the ECDIS screen. He kept turning to port instead of stopping engines or going astern. Had a master and a lookout been on the bridge, the report argues, the starboard swing could have been seen at 1.5 to 1.8 miles.

The steel explains the 11 minutes. Coiled plate is dense, shifts, and leaves no reserve buoyancy once a side shell opens. A 2022-built hull hitting amidships can open a hole that fills the hold before anyone reaches a boat deck. The report flags cargo lashing and hold flooding as items still to be checked. Owner Tahsin Doğruyol said his master had warned Alsu twice before impact. Radio logs will settle that claim.

The Sea of Marmara traffic-separation scheme is one of the busiest short-sea lanes in the world. Ships in that lane are supposed to be visible to each other by AIS, by radar, and by eye. On this night one ship was electronically dark and the other had a half-manned bridge. Six crew of Alsu were later referred to court. Ten men from the steel carrier are still in the water. The preliminary report's sentence that will matter in court is the one that says the sinking was preventable if a lookout had been standing on the tanker.