Domino Effect -Broken porthole causes oilrig to capsize killing everyone aboard : LUSENET : TimeBomb 2000 (Y2000) : One Thread

The results of an inquiry into the Ocean Ranger disaster off the coast of Newfoundland


A small safety glass porthole in the ballast control room aboard an Oil Platform was broken by a rogue wave during a major, but not uncommon, North Atlantic storm.

Water entered the control room and shorted out the circuits controlling the automatic ballasting system.

When the rig started to list, operators tried to manually override the system but were unable to do so, perhaps because of inadequate training (rig owners said they should have been able to do this).

The pontoons on one side of the rig began to take on more water instead of pumping it out (rig stability is controlled automatically by adjusting the level of water in each of the pontoons (legs)).

The rig began to list more and more until it capsized, killing all on board (140 or more I think). This happened with ocean going supply vessels standing by helpless to do anything.

Lawsuits followed which were settled out of court.

Comment: A small non-technical glitch turned a non-event into a major disaster. So when industry, government and others say that the only thing we will experience in Y2K are small glitches, Buyer Beware

-- jim P.E. (, February 17, 1999


Sorry for some of the misinformation but here is a synopsis of the disaster. The inquiry results are availible on the Canadian Govn'ts Royal Commission site. Use search engine.

Early Monday morning on Febtuary 15,1982, the giant drilling rig Ocean Ranger capsized and sank on the Grand Banks, 300 km east of St. John's. The entire 84- man crew perished in the violent winter seas, marking the worst Canadian marine disaster in decades. It was the world's second worst catastrophe in offshore drilling history, next to the North Sea tragedy on March 22, 1980, when 123 died.

The deadly Ocean Ranger storm began as a weak disturbance in the Gulf ot Mexico on Friday the 12th. By Saturday evening it was centred south of Nova Scotia, collecting its strength and moving toward the Avalon Peninsula of Newfoundland. By Sunday atternoon the storm was located near St. John's and had a central pressure of 95.4 kPa. For most of the 14th the rig was battered by hurricane-force winds that reached 168 km/h and by waves as high as a five-storey building. The rig soon developed a list of 12 to 15 degrees on the port side. In the early hours of the 15th the order went out to abandon the Ocean Ranger for the stormy North Atlantic. Soon after daybreak the world's largest semisubmersible offshore rig slipped beneath the wild seas off Newfoundland.

Search and rescue crews battled poor visibility in freezing rain and snow, as well as freezing spray, turbulent seas, and buffeting winds in an attempt to locate survivors. But there were none, The storm also contributed to the sinking of the Soviet container ship Mekhanik Tarasov with a loss of 33 lives about 120 km east of the site where the Ocean Ranger sank.

-- Jim P.E. (, February 17, 1999.

Question: why wasn't that crew evacuated? The storm's strength and size was clearly seen at least 24 hours before it smashed into the Ocean Ranger. What's Standard Operating Procedure for this? Sit tight and hope for the best?

Wonder if this ties in with DGIs asking GIs, "Won't you be embarrassed if nothing goes wrong?" As if one's ego should prohibit heading for higher ground. Did that crew stay put because there was concern about being embarrassed? Hope not.

-- Mac (, February 17, 1999.

Mac: Right! "Hasn't ever happened before, so why would it happen now?" Besides, it would cost money to evacuate everyone. If nothing did whoever made the decision to evacuate would be updating his resume or learning the streets of Boston in prep for new career as a cabdriver.

-- A (, February 17, 1999.

It is physically impossible to "evacuate" under those conditions - no way, can't be done. You can't "hover" a helicopter at all, much less hover close above a listing oil rig to pull them up - even assuming that a sling or rope harness could be controlled so it could be "grabbed" from below. At 80-100 mph winds - the rope is "dragged sideways" from the helicopter.

Could they have evacuated locally - only by going on deck (under the freezing waves washing the decks?) and crawling onboard a self-righting, covered, direct-ejection, self-bailing lifeboat. Those are not usually installed - but are becoming available. Access (under these conditions) has to be under shelter - and that shelter must be "hard-mounted" (steel plate, reinf ribs, locked portholes, locked and dogged hatches, etc.) to avoid itself from being torn to pieces.

If the access to a lifeboat is that well-protected, then it's hard to get into under "normal emergency" conditions (like fire or explosion) when immediate access without any kind of restraint is essential.

-- Robert A. Cook, P.E. (Kennesaw, GA) (, February 17, 1999.

P.E. -- I meant evacuate, like Mac said, before it is impossible to evacuate. (Like prep for Y2k before it is impossible to prepare.)

But evacuating early (maybe -- horrors -- several times a season) would "have negative impact on the bottom line" says pointy haired manager.

Same rationale for not evacuating is the same for not starting Y2K fixes in 1985 (whatever). "It ain't (probably) gonna happen on my watch; forget it."

The manager that is proactive and evacuates the crew, and then it is found out that it was unnecessary (after the fact), is going to be looking for another job (not a "company" guy, not "sufficiently attuned to the impact of excessive and unnecessary costs on the bottom line".)

-- A (, February 17, 1999.

Above was for Cook P.E. not Jim P.E.

-- a (, February 17, 1999.

Those who died (and their families) were probably wishing the same thing ....... but when the decision was made (like that of the Edmund Fitzg. in Lake Superior) "the experts" didn't "think it was going to be so bad." "We've wethered bad storms before." "It's designed to take it."

And as you pointed out - they couldn't escape past certain point in time - and couldn't get "out of the way."

-- Robert A. Cook, P.E. (Kennesaw, GA) (, February 17, 1999.

The reason she wasn't evacuated was the rig was supposed to be hurricane proof. Apparently the only reason she sank was because of the broken porthole. The gist of posting this was to show that a small glitch can have terrible consequences.

-- Jim P.E. (, February 17, 1999.

"for the want of a nail"

-- Charon (, February 17, 1999.

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