I saw 2 props on the Science Channel show Building Giants that Mark can't handle. They were for a cruise ship 1100 feet long and 141 feet wide that has a total tonnage of 171,500. The props have 5 blades, are 20 feet in diameter, and weigh 33 tons each. Turned by over 50,000 horsepower they push that ship up to 28 knots with an average speed of 22 knots - and the ship doesn't even have a pad. Pretty impressive.