BOS 400

BOS 400 refers to a semi-submersible heavy lift vessel, and at the time of its loss, the largest of its kind in the world. It was owned by Heerema Marine Contractors, a Dutch company specializing in offshore construction and engineering.

The vessel is best known for its wreck in 1994 off the coast of South Africa. The BOS 400 was being towed by the Russian tugboat Tigr to Saldanha Bay for maintenance when the towline parted during a storm. Without its own propulsion, the BOS 400 drifted aground at Duiker Point near Sandy Bay.

Attempts to refloat the BOS 400 were unsuccessful, and the wreck remains a prominent feature of the coastline. While considered a hazard to navigation in its immediate vicinity, the wreck has also become a popular diving site, although this can be dangerous due to the vessel's deteriorated condition and strong currents. The incident highlighted the risks associated with long-distance towing of large vessels, particularly in adverse weather conditions. The BOS 400 continues to serve as a cautionary tale in the maritime industry.