Ocean Ranger

Ocean Ranger was a semi-submersible mobile oil platform that sank in Canadian waters on 15 February 1982. It was drilling an exploration well on the Grand Banks of Newfoundland, 267 kilometres (166 mi) east of St. John's, Newfoundland, for Mobil Oil of Canada, Ltd. (MOCAN) with 84 crew members on board when it sank. There were no survivors.

Refloated in 1983 due to its wreck posing a hazard to shipping, Ocean Ranger was towed to deeper water and sunk again. Three divers died in the operation, bringing the total loss of life from the sinking to 87. The loss of the platform led to numerous lawsuits against the owners, which were eventually settled out of court for a grand total of $20 million, and changes in operation and safety standards were enacted to prevent similar disasters in the future.

History and design

Ocean Ranger was designed and owned by Ocean Drilling and Exploration Company, Inc. (ODECO) of New Orleans. The vessel was a self-propelled large semi-submersible design with a drilling facility and living quarters. It was capable of operation beneath 1,500 feet (460 m) of ocean water and could drill to a maximum depth of 25,000 feet (7,600 m). It was described by ODECO as the world's largest semi-submersible oil rig to date.

Constructed for ODECO in 1976 by Mitsubishi Heavy Industries in Hiroshima, Japan, Ocean Ranger was 396 feet (121 m) long, 262 feet (80 m) wide, and 337 feet (103 m) high. It had twelve 45,000-pound (20,000 kg) anchors. The weight was 25,000 tons. It was floating on two 400-foot (120 m) long pontoons that rested 79 feet (24 m) below the surface.