Transocean John Shaw was a semi-submersible drilling rig designed by Friede & Goldman as a self-propelled modified & enhanced pacesetter, built and delivered in 1982 by Mitsui Engineering & Shipbuilding Ltd. in Japan. The Panama-convenience flagged vessel was designed and outfitted to operate in harsh environments. The rig was capable of operations at water depths up to 1,800 ft (550 m) and drilling down to approximately 25,000 ft (7,600 m) using an 18.77 in (47.7 cm), 10,000 PSI blowout preventer (BOP), and a 21 in (53 cm) outside diameter (OD) marine riser.