A ship turns towards you, but are you on a collision course?

James Stevens answers your questions of seamanship - this month, can you judge when and how far ships are turning?

Can you judge when and how far ships are turning?

Question:

Chris is skipper of Petrel, a 29ft cruiser racer. He’s on passage to windward at night with two crew and currently on starboard tack.

The weather is a bit windier than he’d hoped, about 18 knots on the nose and the favourable tide, although handy, is causing an unpleasant sea. He has two reefs and a working jib.

Chris is quite experienced, a Yachtmaster Coastal, and his crew sail regularly with him.

Chris has been watching a passenger ship approaching from astern. It appears to be on a parallel course about three miles to leeward and is well lit and clear in the good visibility.

When the ship is approximately abeam on the port side of Petrel it starts to turn to starboard towards the yacht.

Chris watches anxiously as the aspects of the ship’s lights change. The turn is slow but the ship is now only about two miles away and approaching fast.

Chris can see its starboard light but is unsure whether it will continue to turn and pass astern, in which case he should continue on starboard tack as fast as possible.

Alternatively, if the ship has completed the turn it will pass ahead, in which case Chris should tack. What should he do?

Answer:

This is potentially a very dangerous situation. Although in the open sea the ship should give way, the ship’s lookout may not be aware of the yacht.

James Stevens, author of the Yachtmaster Handbook, spent 10 of his 23 years at the RYA as Training Manager and Yachtmaster Chief Examiner

Chris needs to ensure the ship knows he’s there as soon as possible, he only has a few minutes.

In the confused sea the yacht might be invisible to the ship’s radar. Shining a strong torch on the sails or directly towards the ship would help.

A white or even red flare and a radio call to the ship are worth a try using the handheld radio so he can stay on deck and monitor the situation.

The crew should already be in lifejackets. Chris could motor slowly to windward. It may be uncomfortable but it gives the option of laying on either tack depending on what the ship does.

If it still appears that the ship is unaware of the yacht and is heading for it, Chris is in danger, even if it passes close by they could capsize in the wake.

Chris needs to hold on to the handheld VHF. If he ends up in the water his life might depend on it.

This question is based on the accident report following the tragic loss of the yacht Ouzo and her three crew off the Isle of Wight in August 2006.

A number of recommendations were introduced to improve bridge lookout on ships but the chilling fact was that the lookout did not see the yacht’s navigation light until too late and the yacht did not appear on the ship’s radar.

Enjoyed reading A ship turns towards you, but are you on a collision course?

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