“The heart of US fast battleships, the reduction gears! A man is shown deburring the edges of teeth with a file. They offered almost 10-1 reduction to allow the turbines to run at much higher and more efficient rpm. These are some of the most critical components of the powerplant and one of the things which allowed long ranges in US battleships."
"While steaming with HMS Duke of York, USS North Carolina (BB-55) was found to burn 39% less fuel at the same speed while her hull required more power to achieve that speed than the British ship. Note that they are double helix which eliminates axial thrust while providing the quieter running and increased strength of helically cut gears.”
lonestarbattleship
