What Is a Steering Engine?

A steering engine is a device used to aid in moving the rudder of a large ship. First used in the mid 1800s, the first steering engine was a steam-operated unit used to improve the steering speed of the SS Great Eastern in 1866. The steering engine acts as a type of power steering for a large ship. The enormous size of the rudders used in the manufacture of the largest ocean and river-going ships created a problem when the crew was required to quickly turn the ship's wheel. Some of the first steering engines worked so effectively that the ship's wheels were said to turn like the blades of a fan.

A typical steering engine used a steam cylinder that ran across the axis of the ship's rudder arm, forcing the arm to the port and starboard sides as a mechanical valve was actuated. The power the cylinder applied to the rudder arm made turning the ship an easier task. Many ships went from having several men in the wheel house to having only one to steer the ship. In foul weather, some ships would actually employ several men with block-and-tackle equipment. It was placed from the ship's wheel to the ship's inner steel structure to aid in turning the vessel in rough water.

The job of the steering engine was not simply to aid the crew in steering the ship. In rough water, the rudder was often pushed into an improper position by the heavy seas. The steering engine helped provide the power to hold the rudder in position, and this allowed the captain to order a heading that could actually be maintained in a storm. The maneuvering of a large ship while operating at slow speeds was also improved through the use of the steering engine.

While the typical design of the steering engine has been changed to that of a hydraulically-powered steering cylinder, the central idea has remained the same. Gone are the ropes, chains and gear systems that used to operate the ship's rudder. Modern vessels often use a joystick in place of a ship's wheel to steer the vessel. Similar to the original version of a steering engine, the ship is turned very swiftly with the aid of a hydraulic cylinder applying pressure to the rudder's control arm.