[2][3] On the evening of 27 January 1974, a severe storm caused the 4,576 GRT Captayannis to drag her anchor while she was waiting at the Tail of the Bank to deliver sugar to the James Watt Dock in Greenock.

[2][4] Her captain ordered the engines to be started with the intention of running for the more sheltered waters of the Gareloch but before she could be brought to power she drifted onto the taut anchor chains of the BP tanker British Light.

[2] The tanker suffered no damage but her anchor chains holed the sugar boat below the waterline, allowing water to pour in.

[6] The pilot boats, the tug Labrador and Clyde Marine Motoring's 20 metre passenger vessel Rover came to assist.

[7][8] The wreck is not to be confused with that of the French warship Maillé Brézé which sank nearby in 1940,[9] but was later removed and cut up in Port Glasgow in 1956.