The Loss of the Ocean Ranger

Yesterday was the 40th anniversary of the loss of the semi-submersible Ocean Ranger with all hands, offshore Canada. It was a disaster from which lessons can still be learnt. For those unfamiliar with how it went you can read a brief description here: .

Be prepared to be distressed.


Feb 15th 0600 UTC Surface Analysis

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15 Feb 0000 UTC Analysis Zoomed shows core of 50-65 knot sustained winds west and south of the low center.

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A sad fact is that this accident was one of many involving offshore drilling rigs and barges that happened in the 1970s & 80s, with loss of several hundred lives. Yet didn’t lead to any meaningful change in laws, or operating practises.

In all cases the unclear “Chain of Command” and lack of maritime knowledge by the person(s) making crucial decisions was found to be a major factor, if not direct cause of the accidents and the large number of casualties.

The only thing that came from it was that the introduction of an OIM Certificate to pay lip service to the recommendations in the Accident Reports,
This was based on a 5-day “OIM School” and 2 years of “Offshore experience” to make a Driller qualified to be “In Command” (PIC) of a Semisubmersible Drilling Rig with >100 persons on board, operating anywhere in the world. (except Norway).


Agreed. Like you, I came from a maritime background to the offshore industry. . . quite the eye opener.

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In 1976 I was assigned as MWS for the departure of what was then “the world’s biggest Semisub” Ocean Ranger from the building yard in Hiroshima, heading to the Gulf of Alaska for her first drilling job…
Because of an accident with a Aker H4 rig in Norway a few months earlier:

The Deep Sea Driller shipwreck in 1976 was the first major accident on the Norwegian shelf, but is not included in overviews of oil accidents. Six men were washed into the sea and drowned when a lifeboat capsized, among them the Captain, who was initially blamed for heading towards the coast in a storm and without tug assistants.
PS> The Master/OIM on Norwegian rigs was always required to be Master Mariner, but after this accident also with additional special training.

For this reason I was given clear instruction that to sail without tug(s) was not approvable.
When I got to inspect the rig at the yard I found that it had second hand diesels for the generators and refurbished ex WWII vintage Submarine electric propulsion motors, which was common for ODECO designed and owned rigs

The rig was owned 50% by a Norwegian shipping company at the time, who had insisted on insuring their half with the newly established Norwegian Insurance Pool. (ODECO was self-insured)
PS> The Norwegian company sold their half to ODECO long time before the accident off Newfoundland.

They had also insisted on having lifeboats, not just rafts and Carley floats, and a modern computerized Ballast Control Panel, which unfortunately was placed in one of the small columns, far way from the bridge, anchor control room and living quarters.

The marine crew were Norwegian mariners, while drill crew were Americans. There had already been problems when the Toolpusher tried to give instructions to the Ch.Eng about how to run his Engine room. (And insisting on calling him the Mechanic)

While loading up supplies for the first well, (Dry bulk, Drill water, Casings etc.) the rig suddenly developed large trim by the bow. The Ballast Control Operators (all ex tanker Mates) attempted to make correction by pumping ballast from Fwrd. That resulted in and even larger trim by stern. The Captain run down and manage to control the trim by filling counter ballast and get a deeper draft.

With all the supplies on board the pontoons were under water by a couple of feet, which was not acceptable for transit. Besides, the “free running speed” obtained was only abt.2 kts. on trial.
It was also found that the generators could only be run at 60-70% capacity due to the warm seawater in the Inland Sea. (Cooling system designed for 10C seawater temp.)

On top of that the plan was to proceed without tug assistance for the voyage across the Pacific and through the Aleutian Island chain
Consequently I refused to sign CofÀ for departure, unless the rig was assisted by a suitable tug.

ODECO protested and wanted to throw me off the rig, while the Norwegian part-owner and their insurers agreed with me. Eventually we came to a compromise, which was that a tug (inspected and approved by me) would be attached until 200 n.miles from the Japanese coast, where the water would be colder, the draft lighter and with plenty of sea room to drift in. Also a tug in attendance when passing through the Aleutian Island chain.

PS> The rig arrived in Alaska without any problem.

A little anecdote:
ODECO had two rigs under construction at the same time at the yard in Hiroshima, the Ocean Bounty and Ocean Ranger.
The two Owner’s Rep teams sheared an office and inevitably there were some “friendly competition”.

The Ranger team had got made a poster saying:
BIIIG Rig, BIIG Problems!!
Small rig, Small problems

Underneath somebody had penciled in;
NO Rig, NO Problem.

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I think it was ODECO that liked to put those Fairbanks-Morse OPs on their rigs. US Diesel subs either had those engines or Cleveland Diesels (precursor of EMDs).

Yes it was second hand diesels and electric propulsion motors, all WWII vintage from submarines.
Another peculiarity was the dimensions of everything. I noticed especially the Lifeboat davit supports; the davits were standard Harding supplied but the rest of the structure was built by the shipyard from ODECO drawings.

I asked ODECOs Chief Designer (who were proudly showing me around when I was still in the good book. before he instructed all ODECO personnel not to talk to me) why?
He explained; “I let those young Engineers make their calculation on their fancy computers, then I’ll double it”.

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