Liftboat
A liftboat has a relatively large open deck to accommodate equipment and supplies, and the capability of raising its hull clear of the water on its own legs so as to provide a stable platform from which maintenance and construction work may be conducted.
Because the pads of the liftboat are sitting on a muddy, unstable seafloor, most liftboats practice a safety measure called a preload, where the boat jacks-up the absolute minimum to clear hull from the tips of the significant wave heights,[3] fills its holds with water for weight and allows the boat to settle in the mud for several hours before dumping the water and jacking up to work height.
However starting in the early 2000s, U.S. liftboats were contracted to work in international markets including Brazil, Nigeria, the United Kingdom and China.
These SEPs range in size from small platforms designed for the Gulf of Mexico to large units up to 115 m in length, capable of installing offshore wind turbines and foundations exceeding 800 tonnes.
ORCA platforms can be configured for construction support, light drilling, well intervention, well plug and abandonment, coiled tubing operations, wind farm installation, gas compression and accommodation.
[10] On November 18, 2018, the Ram XVIII overturned at a location in the Gulf of Mexico about 15 miles (24 km) south-southeast of Grand Isle, Louisiana.
The National Transportation Safety Board (NTSB) determined that the probable cause of the accident was an industry failure of not providing liftboat operators with enough information about composition of the seafloor.
[11] On September 8, 2019, the Kristin Faye liftboat overturned while servicing an oil platform in the Gulf of Mexico about 18 miles (29 km) east of Venice, Louisiana.
[14] The ship was about 7 miles (11 km) into a voyage from Port Fourchon to an oil platform on the other side of Louisiana's Mississippi River delta.
Captain David Ledet, age 63, of Thibodaux, had remained in the wheelhouse calling "mayday" even though the vessel was in trouble; he stayed at his post and continued seeking help for his crew, and was later found deceased.
