Ok. This is in my wheelhouse, so to speak, so I will try to make some cogent comments.
From 1983 through 1987 I was the general manager of a company that owned and operated six liftboats that were, at the time, the largest of the class. These boats, through a series of company acquisitions, are now in the Power Boat Rentals Fleet which itself is now part of Seacor. The capsized vessel in question was not one of these since it was built long after I left.
The first thing to realize is that when originally conceived and built, liftboats were much smaller and only worked in the bays and marshes that were the hub of the Louisiana oil industry. As the offshore fields developed, a company called Blue Streak Industries introduced a deep water version of the boats with 130’ leg lengths capable of operating in 60’ water depths. At the time there were no USCG rules for inspection of these vessels so they operated outside of the USCG certification process. They were built as lightly as possible so that they could be jacked up with fairly lightweight rack and pinion jacking systems. Making them lightweight generally meant 1/4” steel shell plating, widely spaced framing, shallow hull depth resulting in low freeboard and an aluminum topsides structure . Hull form was generally box shaped, flat bottom, slab sites, flat deck, a simple raked bow and minimal watertight hull compartmentation.
I ended up with this job due to a partnership with my company which owned an offshore capable crane barge with a lift capacity of 550 metric tons. Our crane barge was mostly used in the marine salvage business and could easily pick a liftboat out of the water.
To say that I was horrified by the construction standards of this type of vessel was an understatement. There was no oversight of design or actual construction by any regulatory body at that time. I was put in a position of managing what I considered to be unsafe boats. As it turned out, the accident rate for liftboats was so great during the 80’s that the USCG proposed regulating them to the same standards as offshore drilling rigs. Not a single liftboat in operation at the time could come close to that standard. A lobbying body for the offshore community (the Offshore Marine Service Association, OMSA) proposed to the USCG that they be allowed to write the technical and operating standards for the Notice of Proposed Rulemaking which would become the CFR rules for this type of vessel. At the time the USCG budget was being tightened so they gladly accepted this offer. More than that, regulation of liftboats required study of some very technical elements that the USCG did not have the technical expertise to undertake. OMSA formed a technical committee to study the issue and propose the rules. I was appointed to the committee as one of 6 members. The other five members came either from other operating companies or designers of existing liftboats.
I won’t go into the politics of the deliberations other than to say I was outvoted on nearly every issue from construction specifications to manning requirements. Stability was completely ignored. The OMSA recommendations eventually became the USCG inspection requirements. The boats constructed there after became bigger and more sophisticated but the minimalistic construction, stability and operational requirements remain. USCG safety standards have improved requiring much sturdier lifesaving gear in the event of disaster. But little has been done to prevent the actual disaster from occurring.
During my career with that company and later with others in the marine salvage industry, I have been involved in the investigation or salvage of 10 sunken liftboats. Several have involved loss of life or significant injury.
Here are a few of my observations based on my experiences:
1). Crewing requirements are minimal. Boats are built to take advantage of admeasurement loopholes so that most liftboats have a grt of less that 100 tons. So the requirement is for a Master with a 100 ton license and two deckhands. Most times a cook is added to support contractor crews. This for a vessel that operates 24 hours a day. I do not know if this is the case for the boat in question but it is typical.
The remaining personnel that may be aboard are from contracting crews who are on board to perform oil industry related tasks and are using the liftboat as a platform for their equipment and a hotel for sleeping and eating. These contractors normally have no affiliation with the liftboat operators and are not considered crew.
Typically contractor crew do not ride on the liftboat to and from the offshore location. They are brought separately either by helicopter or crewboat. The fact that there was contractor crew on board the liftboat during the transit speaks to the suddenness or unpredicted nature of the storm that didn’t allow the oil company for whom they were working enough time to get them off before the boat had to make a run for it.
2) Liftboats cannot jack the boat out of the water in a greater than 3-4’ wave height. This is because the jacking speed is slow and for the critical time that the pads on the bottom of the legs are close to the sea floor, the rise and fall of the boat creates a slamming of the pads on the sea floor until such time as the boat is elevated above the sea and it’s buoyancy is no longer a factor. Attempting a jacking sequence in greater sea states always results in serious damage to the legs and jacking systems and has resulted in the catastrophic failure and collapse of the system in the past.
3) Remaining jacked up on site to ride out a storm may be risky also. If they are at a deep site, the leg extension may not provide enough air gap between the sea and hull bottom to prevent large waves slapping on the hull and knocking it over.
4) Lowering the legs to increase stability while underway is rarely feasible. Look at a chart of the Gulf of Mexico just south of Fourchon. Shallow water extends out more than 20 miles. When in high seas in shallow waters if you lower the legs even a little you run the risk of slamming the pads on to the bottom. See 2) above.
5) Stability is critical on liftboats. Raised legs decrease the stability significantly. Quite often the contractors equipment on deck is very heavy. This reduces stability even further. I have seen righting moments of less than 6” on vessels that really need 3’. Mostly this equipment is secured with truck chains and binders. If a piece breaks loose and is washed to one side, very bad things will happen. Another issue is the flat deck with no camber. This allows water to slosh back and forward placing strain on the securing. It is not safe to go out on deck when the sea is washing on board.
6). Low freeboard and no shaped bow plus no solid bulwark allows seas to wash over the deck in just a 4’ sea state. These vessels should never consider being underway in a sea state greater than 10’. It is a recipe for disaster.
All in all this tragedy was preventable but politics and corporate greed won out over solid engineering and good operational practice. I believe nearly all of the members of the OMSA committee have now passed, I was the youngest and am now 67. Now, the operators will cry out that they were in compliance with all applicable regulations and had recently passed a safety inspection. But the reality is, these machines should never been built in the first place.