The semi-submersible “flotel” (floating hotel) Alexander L. Kielland capsized on 27 March 1980 while bridge connected to the steel jacket Ekofisk Edda platform. The flotel lost one of its five legs in severe gale force winds, but not an extreme storm. The accident started with one of the bracings failing due to fatigue, thereby causing a succession of failures of all bracings attached to this leg. It was discovered during the investigation that the weld of an instrument connection on the bracing had contained cracks, which had probably been in existence since the rig was built. The cracks had developed over time, and the remaining steel was less than 50%.
Officer of the Watch 