Features of using the autopilot on a yacht
Denis Korablev
  • 07.10.2021
  • 651

Features of using the autopilot on a yacht

The last decades have been marked by an incredible increase in information about new technologies, which literally a few years ago seemed to be a figment of the fantasy of Hollywood directors. Electronic devices, by themselves, and integrated into systems, began to monitor our health, monitor our homes, take care of our children, help us find our way home if we get lost.

Can such smart devices help a tired skipper bring his beautiful yacht to the desired port? It turns out that this is no longer a dream, but a real life, with the arguments about "pro" and "contra" on this issue following from this fact. It's about autopilot. No, not about the one who is driving the car, but about the autopilot on the yacht, an invisible helper, eliminating the need to maintain a round-the-clock watch at the helm of the ship, which is very convenient for the person being handed over yachts for rent and in case of a long trip on your own yacht.

By the way, the idea of creating a disembodied assistant in yacht management is not an idea of recent years, and not even of the 21st century. The beginning of the last century was distinguished by an abundance of bold technical solutions, especially in shipbuilding and navigation. There was a competitive race for the right to be considered the best, first and only on the sea. Monsters such as "Titanic", "Britannic" were built and launched, yacht races were held.

The right to be considered the progenitor of the modern autopilot belongs to George Brain, who created the first, albeit a primitive instance of a mechanical steering (there was no talk of electronics then). The original system of the inventor - the yachtsman was a structure connecting the sails and a special drive on the rudder stock. A sharp gust of wind or the resulting heel set in motion the system, which consisted of blocks, rubber bands and ropes, the feather changed its position, due to which the yacht was propelled, throwing the wind from the sails. The ship was returning to its previous course. Simple and ingenious! Naturally, such a design cannot be called perfect, the Brain system had to be reinstalled every time the tack was changed, but a bold idea, implemented even before the outbreak of the war that swept the whole world, is worthy of respect.

The Port Louis Maritime Museum can be proud of a unique exhibit - the first such as an auto steering wheel. A large area wind wing, connected to the rudder with ropes, helped Marina Marie to successfully complete the solo passage from New York to Le Havre. In 18 days, the brave Frenchman made a transatlantic crossing back in 1936.

Further improvements in the design of mechanical autopilots were carried out in the 50s of the last century by the British J. Major and M. Henderson. These designs were based on the principle of using a small wind wing, which could control the flap on the rudder. The designs of ropes and blocks, albeit improved, basically repeated the idea of D. Brain. Electronics broke into yachting only in 1970 when the first electronically assisted autopilot from Tillermaster was created.

So what is modern autopilot?

The companies Aries, Beafort, Capehorn, Fleming, Monitor, Holland and dozens of their competitors produce various models of autopilots, updating and replenishing the market with advanced electronic steering assistants every year. Basic models are divided into two categories: with servos, and the same, but with an additional auxiliary pen included. The prices of the offered autopilot models do not differ significantly, however, the models with an additional feather are 25-40 percent higher than those of the basic models of the servo autopilots. This difference is due to the high cost of the material used in the manufacture of the auxiliary pen. Such a feather, in the raised state, does not create obstacles on the move, and maneuvering in narrow places and under the motor is greatly simplified.

The functional purpose of yacht autopilots is defined as an electronic system designed to keep the yacht on a certain course without human intervention. The system, consisting of a heading computer, an integrated induction compass and a control module, using the servo drives of the drive mechanism, can change the position of the rudder. The autopilot drive is connected and disconnected using an electromagnetic relay (clutch).

The functional purpose of autopilots for a yacht is defined as: "An electronic system designed to keep a yacht on a certain course without human intervention." The system, consisting of a course computer, a built-in induction compass and a control module, can change the position of the rudder using the servo drives of the drive mechanism. In real conditions, it works in the following sequence: a person using the "auto" button initiates the inclusion of the course computer, which automatically fixes the selected course. Using the same control module - controller, you can correct the necessary corrections. The course is displayed on the liquid crystal display. When the yacht deviates from the selected course to the right or to the left, the computer fixes this (induction compass!), Turns on the drive mechanism, which, with the help of servos and cables, changes the position of the rudder, returning the boat to the selected course. The connection of additional elements of the system is carried out according to special protocols promoted by the largest manufacturers of drives (NMEA 0183, NMEA 2000, Sea Talk, SimNet, FDX). Actuators that convert the electrical signal from the course computer into mechanical force, which is transmitted to the steering wheel.

Everything seems to be simple - I entered the steering heading, if necessary, made an amendment by a couple of degrees, and can enjoy the rest. But with all the advantage of the presence of such an electronic assistant on a yacht, there are moments indicating that even the most modern device will not be able to fully replace a person at the helm.

What are the negative characteristics of using autopilot in yachting?

When the computer is turned on, the built-in induction compass gives the computer an initial heading, which the course computer will strictly adhere to, and correct any deviations using the rudder actuators. At the same time, constantly steering to save the course recorded in memory, the autopilot will do this using the rudder pen and, oddly enough, the steering wheel. If, when the autopilot is turned on, the steering wheel is twisted, or attempts are made to steer independently when the autopilot is on, breakdown of the latter is inevitable. Quite often, the computer output from the induction compass does not correspond to the true or compass heading. The discrepancies between the true (GPS), compass and displayed heading can be up to 15. You cannot completely trust the absolute heading displayed on the autopilot module. The computer is not yet capable of independently analyzing and eliminating the differences in the readings of navigation devices.

Autopilot, as you know, needs energy to work. A computer system, servos of regular autopilots - all electronic devices "pump" electricity from the onboard batteries. Electricity consumption when using autopilot on a sail-balanced yacht is 3-4 amperes, and is capable of increasing up to 10 amperes in stormy conditions. In case the yacht constantly leaves the course under the influence of wind or significant waves, and at the same time the autopilot is on, the onboard batteries are fully seated. Adjustment of the set course is a direct function of the autopilot, and since it uses electric motors of the drives powered by service batteries, their discharge is inevitable.

In general, using the autopilot in fresh wind and rough conditions is not recommended. When the boat, under the influence of external forces, actively leaves the course, the drive power of the standard autopilot is clearly insufficient. Practice has shown that turning on the autopilot is generally contraindicated on a sailing yacht. If, on the backstay, for example, the helmsman is trying to prevent the boat from overshooting with a pre-emptive rudder movement, then the activated autopilot is not designed to work pre-emptively, and only monitors the deviation from the course, constantly adhering to it. This can lead to uncontrolled bringing to the wind, turning the lag to the water, and other unpleasant consequences. There is only one conclusion: on fordewind and full backstay, it is absolutely impossible to turn on the autopilot, even in calm water.

According to experts 2yachts, no matter how advertising skippers praise the advantages of an autopilot, making it invisible, but very As a helpful team member, there is one thing to keep in mind. An autopilot is, first of all, an electronic machine that accurately performs the task assigned to it. And this machine is not yet smart enough to make decisions and react to dangers, completely replacing a person. The autopilot cannot be compared to either the radar or the helmsman's eye, it cannot track and analyze the situation in the water area. This is exactly what the instruction on the use of autopilots of all models warns about: "Automatic heading control greatly simplifies the control of the vessel, but it is not able to completely replace a person." There is nothing to add to this.

It is quite possible that new developments of autopilots with artificial intelligence, will be able to expand the useful capabilities of the autopilot, but one thing is clear - he will not be able to replace a person.