A helmsman or helm (sometimes driver or steersman) is a person who steers a ship, sailboat, submarine, other type of maritime vessel, or spacecraft. The rank and seniority of the helmsman may vary: on small vessels such as fishing vessels and yachts, the functions of the helmsman are combined with that of the skipper; on larger vessels, there is a separate officer of the watch who is responsible for the safe navigation of the ship and gives orders to the helmsman, who physically steers the ship in accordance with those orders.
In the merchant navy, the person at the helm is usually an able seaman, particularly during ship arrivals, departures, and while maneuvering in restricted waters or other conditions requiring precise steering. An ordinary seaman is commonly restricted to steering in open waters. Moreover, military ships may have a seaman or quartermaster at the helm.
A professional helmsman maintains a steady course, properly executes all rudder orders, and communicates to the officer on the bridge using navigational terms relating to ship's heading and steering. A helmsman relies upon visual references, a magnetic and gyrocompass, and a rudder angle indicator to steer a steady course. The mate or other officer on the bridge directs the helmsman aboard merchant or navy ships.
Clear and exact communication between the helmsman and officer on the bridge is essential to safe navigation and ship handling. Consequently, a set of standard steering commands, responses by the helmsman, and acknowledgment by the conning officer are widely recognized in the maritime industry. The helmsman repeats any verbal commands to demonstrate that the command is heard and understood. The International Convention on Standards of Training, Certification and Watchkeeping for Seafarers (STCW) requires that a helmsman be able to understand and respond to helm orders in English.
The proliferation of autopilot systems and the increased computerization of operations on a ship's bridge lessen the need for helmsmen standing watch in open waters.
Helm commands
Helm orders or commands fall into two categories: rudder commands and heading commands. A rudder command dictates changing the angle of the rudder, which is a single-event action, whereas steering a heading is a comparatively long event and will require ongoing or continuous rudder adjustments.
The following are helm orders used in the United States Navy and United States Coast Guard:
Rudder
Midships (Bring rudder angle to 0 degrees) Meet Her (Counter steer to stop the movement or swing of the ship's bow) Hard rudder (Used infrequently, such as emergencies, when maximum rudder is required) Left or right standard rudder (~20 degrees. Varies per ship) Shift your rudder (Steer the same number of degrees but opposite rudder angle)
Heading
Steady as she goes (Steer as needed to continue current heading) Steady on a course (Steer as needed to bring ship on desired course)
Acquired skills
Steering a ship effectively requires skills gained through training and experience. An expert helmsman has a keen sense of how a particular ship will respond to the helm or how different sea conditions impact steering. For instance, experience teaches a helmsman the ability to correct the rudder in advance of a ship substantially falling off course. This requires the capacity to anticipate the delay between when the helm is applied and when the ship responds to the rudder. Similarly, a skilled helmsman will avoid overcompensating for a ship's movement caused by local conditions, such as wind, swells, currents, or rough seas.
Ship simulators
Computer-based ship simulators provide a training environment for learning skills to steer a ship. Training can be programmed to replicate a variety of ship sizes and environmental conditions. Scenarios depicted in 3-D graphics range from making course corrections in open waters to maneuvering in port, rivers, or other shallow waters. Cost compared to a real vessel is low. Mariners learn responses to dangerous situations, such as steering failure, in the safety of a virtual environment.
Land-based ship simulators may feature a full-scale replica of a steering stand with a ship's wheel. Such simulators incorporate magnetic and gyro compasses (or repeaters) for steering. Moreover, a rudder angle indicator that responds appropriately to the helm is part of the configuration.