TT Seawise Giant—earlier Oppama; later Happy Giant, Jahre Viking, Knock Nevis, and Mont—was a ULCC supertanker and one of the longest self-propelled ships in history, with only the Prelude FLNG surpassing her.[5] She was built in 1974–1979 by Sumitomo Heavy Industries in Yokosuka, Kanagawa, Japan. The ship possessed the greatest deadweight tonnage ever recorded. Fully laden, her displacement was 657,019 tonnes.At the time she was built, she was the heaviest self-propelled ship of any kind. With a laden draft of 24.6 m (81 ft) and a length of 458.45 m (1,504.1 ft), she was incapable of navigating the English Channel,[6] the Suez Canal or the Panama Canal. She is generally considered the largest self-propelled ship ever built.[7][8] In 2013, her overall length was surpassed by 30 m (98 ft) by the floating liquefied natural gas (FLNG) installation Shell Prelude, a monohull barge design 488 m (1,601 ft) long with 600,000 tonnes displacement. Seawise Giant's engines were powered by Ljungström turbines.She was damaged in an airstrike in 1988 during the Iran–Iraq War but later repaired and restored to service.[9] The vessel was moored off the coast of Qatar in the Persian Gulf at the Al Shaheen Oil Field in 2004 and converted to a floating storage and offloading (FSO) unit.[10]Seawise Giant was sold to Indian ship breakers and renamed Mont for her final journey in December 2009. After clearing Indian customs, the ship sailed to Alang Ship Breaking Yard in Alang, Gujarat and beached for scrapping, which was completed in 2010.[10][11]