AUTOPILOT

For any passage making boat or yacht, an autopilot is a necessity. The thrill of steering a boat on the open ocean is quickly diminished when one realises how tiring it is especially if there are many more hours ahead. An autopilot gives you the ability to accurately navigate to a point without having to touch the helm. In many ways an autopilot, especially if fitted with a rate gyro compass and interfaced with a chartplotter, can out steer and navigate a straighter course than even the most seasoned skipper (and it doesn’t get hungry or thirsty!!).

Autopilots comprise of several main components:

• The Head Unit – this is the controller for the autopilot. Every manufacturer has different styles to suit various applications and tastes. Many can have multiple stations and be wireless giving the skipper the ability to tend to lines and rigging while underway or just sit on the deck and enjoy the surroundings.
• The Course Computer – this is the brains of the autopilot. It basically takes the information from its sensors/GPS chartplotter and tells the drive unit which way to steer the boat.
• The Drive Unit - this creature steers the Rudder, stern drive or outboard. There are several types or drive units with the most popular being hydraulic drive (for hydraulic steering), rotary drive (for chain steered yachts), linear drive (for mechanical steering) , wheel drive (attached to the helm wheel) and tiller drive (attached direct to the tiller).
• The Rudder Angle Indicator – This device tells the course computer what position the rudder is, thus allowing the course computer to calculate how much rudder or counter rudder needs to be applied.

When selecting an autopilot you first need to select your drive unit to suit the steering mechanism of the boat. Secondly, select a course computer/corepack. This is sized to the boats size and weight. The key point here is not to undersize a system for when the seas are rough, you do not want the system struggling and or worse, failing. The final step is to select a head unit to drive the system.

You quickly realise how useful an autopilot is when correctly sized and installed.