In February 2014 Transocean announced that the Deepwater Navigator was classified for sale after the completion of its drilling campaign offshore Brazil for Petrobras. The drillship was then scrapped. Deepwater Navigator was the ex- Sedco 445, part of the offshore drilling history. The Sedco 445 was built for Shell in 1971 by Mitsui at Tamano shipyard, Japan.
Prior to 1970, several coring vessels, including the Eureka, Caldrill and Glomar Challenger, were using an elementary form of dynamic positioning by holding the ship over a designated area. In early 1970, Sedco, in conjunction with Shell International Petroleum, began to develop a new generation drilling vessel that could operate without anchors.
The Sedco 445 is considered as the first offshore drilling unit to work without anchors, introducing a much more reliable and accurate system to safely conduct exploration drilling activities with 100% back up on all station keeping equipment. The Sedco 445 was also the first DP rig to use a riser and a subsea blowout preventer.
From 1972 to 1973 the Sedco 445 drilled wells off South Java for Shell in 1200 ft of water. In 1974 the drillship drilled Shell’s Astarte Marine-1, offshore Gabon, in a water depth of 2100 ft. The first deepwater drilling at that time.
Sedco 445 became Foresight Driller in 1990, Flex LD in 1994, Deepsea Worker in 1995 and the Pregrine VII in 1997. In April 2000, Cammell Laird shipyard in the UK converted the vessel to a deepwater Class I drillship capable to drill in 7,200 ft of water. The work involved the insertion of a 31m new mid-section and full length sponsons,
Acquired by Transocean, the Peregrine VII was named Deepwater Navigator. Transocean achieved a remarkable performance keeping the drillship working until the 31 December 2015.