Question 380Navigation General

70% to pass

The lock chamber is 600 feet X 110 feet. Your towboat is 150 feet X 35 feet. Which of these tows will require a double lockage?

A A set-over single
B 4 standard barges abreast next to your boat's head and 3 jumbo abreast in the lead
C 6 jumbo (3 abreast and 2 long) with a standard on each side of your boat
D 9 jumbo barges
AI Explanation

The correct answer is D) 9 jumbo barges. The dimensions of the lock chamber (600 feet x 110 feet) are not large enough to accommodate the combined size of the towboat (150 feet x 35 feet) and 9 jumbo barges, which would require a total width of 105 feet (3 abreast) and a total length of 450 feet (9 barges). This would exceed the lock chamber's dimensions, necessitating a double lockage. The other options, such as a set-over single, 4 standard barges, or 6 jumbo barges, would all fit within the lock chamber's dimensions and could be locked through in a single pass.

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