On an early afternoon last month, the Eugen Maersk (the world’s longest ocean freighter at 1,300 feet) has left Rotterdam, the Netherlands, on the tail end of a journey from Shanghai. But the giant freighter is cruising at 10 knots, well shy of her 26-knot top speed. At about half speed, fuel consumption drops to 100-150 tons of fuel a day from 350 tons, saving as much as \$5,000 an hour.
The German Preussen (picture above), the largest sailing ship ever built, was launched in 1902 and travelled mainly between Hamburg (Germany) and Iquique (Chile). It was rammed by a large steam vessel in 1910. A one way trip between Germany and Chile took the cargo vessel between 58 and 79 days. The best average speed over a one way trip was 13.7 knots. The lowest average speed was 10 knots.