A wide variety of in-house and contract research studies have been undertaken by the Ocean Engineering Research Centre "(OERCI to examine the performance of several new offshore evacuation and retrieval systems. Wave tank testing was used to examine the deployment of free-fall and generic preferred orientation and displacement systems from fixed and floating platforms." Extensive tank testing was undertaken for the development of the" Seascape Escape System for fixed and floating platforms. The performance of a link-lift lifeboat retrieval system was also investigated. Scales used for all these tests varied from 1: 15 to 1 :75.
On the morning of February 15, 1982, the semisubmersible drilling rig Ocean Ranger capsized and sank on the Grand Banks, 170 nautical miles east of St. John's, Newfoundland, Canada. The entire 84-man crew was lost in the disaster. The author was retained as a consultant by the Government of Newfoundland and labrador, Petroleum Directorate during their investigation of the loss of the Ocean Ranger (Petroleum Directorate, 19821. A much more comprehensive investigation was subsequently conducted by the Royal Commission on the Ocean Ranger Marine Disaster. The author coordinated the extensive model tests that were undertaken for the Commission by the Hydraulics laboratory of the National Research Council of Canada and the Norwegian Hydrodynamics laboratory (now known as Marintekl. A ballast control simulation study, was carried out with a 1 :25 scale model of the starboard side of the semisubmersible. This study was undertaken by staff members of the Commission and those of the OERC. A variety of ballast water transfer scenarios were investigated and these results provided a valuable insight into the final capsize of the rig. The control panel and model, at a forward trim of 30°, is shown in Fig.1.