Ocean Ranger

1982

Grand Banks, the ballast console, eighty-four Location: North Atlantic, Grand Banks of Newfoundland · Coordinates: 46.50°N 48.50°W · Casualties: 84 · Survivors: 0 · Depth: 80 m · Cause: storm · flooded — Caught in a severe storm on the Grand Banks on the night of 14-15 February 1982. A rogue wave broke a porthole in the ballast control room, shorting the panel and opening ballast valves at random. The crew lacked the training and manuals to override; she listed, lost stability, and capsized in the early hours of 15 February. · Fate: partial salvage · memorial · Type: semi-submersible drilling rig · Tonnage: 20,000 tons · Crew: 84 · Flag: United States (Canadian waters) · Launched: 1976 Semi-submersible drilling rig, the largest in the world when she commissioned, under charter to Mobil Oil off Newfoundland. Caught in a severe storm on the night of 14 February 1982 when a rogue wave broke a porthole in the ballast control room; the shorted panel opened ballast valves at random. She lost stability and capsized in a few hours. 84 dead, no survivors. The Royal Commission report produced the overhaul of Canadian offshore training and the creation of the Canada-Newfoundland Offshore Petroleum Board. The Vessel The Ocean Ranger was a semi-submersible offshore drilling rig owned by Ocean Drilling and Exploration Company (ODECO) and chartered to Mobil Oil Canada for operations in the Grand Banks of Newfoundland. She was built at the Mitsui Engineering and Shipbuilding yard at Tamano, Japan, in 1976 and had been operating on the Grand Banks since 1980. She was 121 metres long, 396 feet wide (at her pontoons), and could operate in water depths up to 460 metres with drilling capability to 7,500 metres subsea. The semi-submersible drilling concept represented, at the time of Ocean Ranger's construction in the mid-1970s, the most advanced generation of offshore drilling technology. Her design consisted of two horizontal pontoons (the "lower hulls") supporting four vertical columns that in turn supported the main operating deck. Ballast water was moved between the pontoons through internal piping to maintain stability in sea conditions. The specific ballast-control system was operated from a ballast control room on the main deck. Her commanding officer (the "toolpusher") in February 1982 was Richard Brooks, 34, a Canadian offshore industry veteran. Her crew complement was 84 people, representing a combination of ODECO employees, Mobil Oil Canada staff, Schlumberger drilling technicians, and subcontractor personnel from various service companies. The Disaster At approximately 19:00 on 14 February 1982 the Ocean Ranger's ballast control room was struck by a freak wave. The wave, estimated subsequently by the Royal Commission inquiry at 20 metres height, impacted the ballast control room's exterior portholes. One porthole was broken by the wave impact. Seawater entered the ballast control room through the broken porthole. The seawater shorted the electrical control system for the ballast valves. The short caused the ballast valves to open at random; the forward pontoons began flooding uncontrollably while the aft pontoons continued in their storm-draft configuration. The specific imbalance of ballast made Ocean Ranger list forward; her list progressed through the evening of 14 February 1982 as her crew attempted to restore manual control of the ballast system. The Ocean Ranger's emergency response plan had been designed for conventional fire or blowout scenarios, not for ballast control failure. The crew spent approximately seven hours attempting to restore ballast control before making the decision to abandon the rig. At 00:30 on 15 February 1982 the toolpusher Richard Brooks radioed his operational control centre that the rig was preparing to abandon. The evacuation of the Ocean Ranger began at 01:00 on 15 February 1982. The specific problem with the evacuation was that the rig's lifeboats had been designed for sea conditions in which the rig was relatively stable; the 20-degree forward list that had developed through the evening