In the early afternoon hours of Sunday June 1, 1975 the jack-up rig Progress Marine II was being towed by the tug Admiral Lee to a new worksite in the GOM. At the time there was a 12 man crew aboard the rig. Some crewmen were resting in their bunks in the living quarters below deck. Others were topside, enjoying the sun.
The rig was approximately 18 miles southwest of Grand Isle, LA when disaster struck. Without warning the rig began to list to the starboard. Instantly it became evident that the top-heavy structure would not recover and was about to capsize.
As the crewmen below decks scrambled to reach the topdeck running on walls - struggling to get out as the room tilted -they were forced back as a wall of water rushed through the deck hatch. While topside the men on deck were tossed into the sea...
A jack-up rig is a barge with adjustable legs. Once on site the legs are lowered to the sea floor and firmly planted, then the hull is "jacked up" about 30 feet above the water providing a stable work platform. The Progress Marine II measured 96 feet long, 50 feet wide and 10 feet deep. Each of its four adjustable legs measured 122 feet in length, permitting the rig to work in water up to 70 feet deep.
The Progress Marine II was also equipt with a mat - a large pontoon connected to legs- that can be ballasted. The mat increases the rig's stability. When the rig is to be moved the legs are raised and the mat is pulled in close to the rig's hull. The raised legs and tall derrick make the rig top heavy when under tow.
At the time of the incident, the Progress Marine II was in roughly 40 feet of water when it capsized, coming to rest at a 110 degree angle. The tops of the rig's two jacked up legs hitting bottom and becoming embedded. It's estimated that the rig capsized in 60 seconds.
On a Shell Oil Co. platform about 600 yards away, crewmen watched as a large plume of black smoke rose into the air as the Progress Marine II's engines went under. Quickly, the Shell rig's dispatcher sent a Mayday to the Coast Guard station in Grand Isle, LA and alerted the Progress Marine home office in Morgan City. LA. where immediately the platform utility boat cast off and a helicopter, sitting on the pad, took to the air.
Six of the rig's twelve crewmen were found floating in life preservers near the wreck. With the helicopter acting as spotter the utility boat rescued four of the crew. The other two were pulled to safety by the Admiral Lee's skipper. But six other crewmen remained missing presumed trapped in the hull of the capsized rig.
The chief of the Coast Guard Search and Rescue Center in New Orleans, ordered several cutters to the scene. A Coast Guard helicopter was dispatched soon after the inital distress call with a team of divers from Global Divers and Contracting, Inc. out of Harvey, LA.
A Continental Oil Co. dispatcher that was on duty in Grand Isle, knew that the tugboat Jean G had a diving crew aboard and was in the vicininty of the wreck. He called the tug which proceeded to the capsized rig. The dispatcher would remain on duty night and day coordinating communications, and requests for equipment and men.
Officials at Progress Marine, Inc. sent the barge Sal Duey to the site and requested additional divers from Ocean Systems, Inc. and Continental Diving. Chuck Mowry, would be the designated diving supervisor and coordinator tasked with rescuing the trapped crewmen.
Meeting with company officials and the rescued crewmen, Mowry obtained sketches of the interior layout and probable location of submerged rig eqiupment. The water around and under the rig was littered with jumbled pipes, broken catwalks and steel walkways, tangled lines, hanging crane rigging and other loose materials. The debris would hamper rescue efforts and present a serious hazard for the divers who were dependent on surface supplied air. To be continued ...