to 243 feet are allowed, but the allowable draft depends on the beam and ranges from 52.5 feet to 36 feet for a wider vessel. Currently, tankers as large as 200,000 deadweight tons can pass through the Suez Canal.

The size of crude oil carriers (tankers) evolved from 10,000 to 20,000 deadweight tons in the 1940s to 1950s to 100,000 deadweight tons in the 1960s and 1970s. At first, size was somewhat dictated by the dimensions of the Suez Canal and the depth of major ports. However, recurring crises in the Middle East spurred the development of larger vessels. In the 1990s and 2000 very large crude carriers (VLCCs) with deadweight tonnage of 200,000 to 319,999 tons and ultra large crude carriers (ULCCs) with deadweight tonnage of 320,000 tons and more entered the fleet. These tankers can transport crude oil from the Persian Gulf around the Cape of Good Hope to deep-water ports in Europe and the U.S. East Coast, or across the Indian and Pacific oceans to the West Coast of North and South America.

At the beginning of 2005 there were 10,126 vessels in the tanker fleet, 7,650 of which were engaged in transporting crude oil. The average age of these vessels is 17.5 years, but it is dropping as the new double-hulled vessels enter the fleet and the older ones are retired. In 2003, the tanker fleet transported 1.7 billion metric tons of crude oil—the equivalent of roughly 12 billion barrels of oil, or nearly two-thirds of the oil consumed each year.3

The largest tankers are too big for most U.S. ports, so oil is off-loaded at sea through a process known as lightering. For example, the TI Europe, a 442,470-deadweight-ton ULCC, 1,246 feet long, picked up 3 million barrels of crude oil in the Persian Gulf, crossed the Arabian Sea, then traveled southeast through the Indian Ocean, past tsunami-ravaged Sri Lanka and the coast of Sumatra, along Java, through the Lombok Strait (between Bali and Lombok islands), northwest through Makassar Strait between Borneo and Celebes, past Mindanao, and into the Pacific Ocean. This route follows or crosses the Philippine Trench and the Mariana Trench—some of the deepest waters in the world’s oceans. A ship lost at these depths will never be found. Beyond Guam, the course is past Hawaii and on to Southern California—a journey equivalent to more than halfway around the world.

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