lowances for unknown factors) were reduced, in the desire to keep costs down and to get maximum deadweight for minimum draft.”1

Now that we know that waves as high as 100 feet exist and occur more frequently than previously thought, what can be done to reduce the number of vessels breaking up or foundering and to reduce the number of crew lives lost every year? A wave of such height, with its steep towering face, could deliver an enormous impact—enough to break the back of the best-designed modern ship built in accordance with today’s standards. Even though such waves occur infrequently, are vessels safe enough?

EVOLUTION OF MARITIME TRANSPORT

In 2005 the world’s merchant fleet comprised 39,932 vessels of 300 gross tons or more with a total deadweight tonnage (dwt) of 909 million tons.2 (See Table 6.)

New and larger vessels, especially tankers and container ships, are being built in record numbers. One of the determinants of vessel size is the depth and width of the Panama and Suez canals. The maximum beam allowed through the Panama Canal is 105.5 feet. This corresponds to a container ship carrying around 4,500 containers, or 4,500 TEUs (20-foot equivalent units), meaning a container nominally 20 feet long. Ships that can traverse the Panama Canal are referred to as “under Panamax” vessels. In the Suez Canal, vessels with a beam of up

TABLE 6 Distribution of Vessels in the World Merchant Fleet

Vessel Type

Number of Ships

Million Deadweight Tons

Percentage of Merchant Fleet Capacity

Tankers

10,126

368

40

Bulk carriers

6,347

319

36

General cargo

16,263

95

10

Container

3,220

99

11

Passenger

3,976

28

3

Totals

39,932

909

100



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