Offshore veteran JL Daeschler brought the historic destruction of the Ocean Prince to my attention.
“At about 2 am on the day of the storm, the rig’s superstructure was torn off during a gale. By 7:10 am about a third of the drilling plattform had dissapared under 60 feet water.”
I didn’t realize that some early North Sea wells were drilled with semisubmersible rigs that were sitting on bottom, ala submersibles.
Per JL Daeschler, “the barge master on Ocean Prince was unsettled about sitting on a sandbank in the North Sea with waves as deep as the water depth, hence accelerating the scouring around the pontoon on the sea bed and distorting the forces on an unsupported hull. On a semisubmersible floating rig there is a great level of compliance between the mooring system and the forces on the leg and bracing. Worst case, you let the mooring go and drift.
It’s noteworthy that: “During the same storm which claimed the ”Ocean Prince,” the rig’s sister ship ”Ocean Viking,” while drilling afloat, withstood winds and waves of equal force.”
The entire crew of the Ocean Prince was safely evacuated. The helicopter pilot’s last name was fitting given his bravery during the rescue!
“Hero of the rescue effort was Capt. Robert Balls, 32, a former naval pilot who was alerted to remove the stranded crewmen. Within 45 minutes after he was awakened at Scarborough Hotel at 6 a.m., he was piloting a Wessex 60 helicopter across the North Sea fighting gale winds 400 feet up.”
“Captain Balls flew the copter with a minimum load of fuel in order to carry more than a full passenger load to the oil rig ”Constellation,” which was drilling about 20 miles south of the ”Ocean Prince.” On the first lift he transported 19 men. Usually, the capacity of the Wessex 60 is 16. On the second trip he took 18 crewmen. The final trip, he flew eight men directly to Scarborough.”
Before the storm:
We just received word this morning that the Transocean Marianas rig has developed a large crack in one of the pontoons on the #5/#6 anchor chain locker while they were picking up anchors, and is currently taking on water and listing. The bilge pumps are keeping up (barely), but there’s certainly concern that it might sink on location. So far, 68 people have been evacuated from location.
Bud's Offshore Energy (BOE) 