Safety and rules · 8 minute read
Offshore autopilot safety
Plan offshore autopilot safety around overboard prevention, lookout duties, alarms, manual takeover and steering failure. Prepare the crew before departure.
The autopilot is the most useful piece of equipment on a shorthanded passage and the one most implicated when things go badly wrong. A boat under autopilot keeps sailing when someone falls off it. A crew that trusts the pilot stops looking. A pilot that fails at 3 am in a rising sea hands the helm to whoever is least rested. None of those are reasons not to use one; all of them are reasons to use it deliberately.
This guide sets out the habits that experienced offshore sailors and instructors teach: how to stay on the boat, how to keep a lookout, how to set alarms, how to take over instantly and what to do when the pilot quits.
Key facts
- Rule 5
- A proper lookout is required at all times, autopilot or not
- Tether
- Clip on before leaving the companionway when the pilot is engaged
- Alarms
- Off-course, XTE, AIS CPA, depth, wind shift
- Override
- Standby or clutch within one movement of the helm
- Backup
- Spare drive, tiller pilot or windvane
Overboard risk while the autopilot is engaged
The defining risk of an engaged autopilot is that the boat does not stop if you go over the side. On a crewed boat with a watch in the cockpit that is a man-overboard drill. On a singlehanded or two-handed boat with the other person asleep, it is usually fatal. Australian coastal waters are cold enough in the south and remote enough in the north that the outcome does not depend on luck.
The answer is the tether. A harness clipped to a or a hard point every time you leave the companionway with the pilot engaged, day and night, calm or rough. Instructors teach it as a reflex, not a judgement call, because judgement is what fails at 2 am.
- Jacklines rigged inboard so a fall keeps you on deck, not in the water
- Short tether for cockpit work, longer only when moving
- A remote control clipped to the person, not the boat, so the pilot can be stopped from the water only if the remote reaches
- MOB button on the plotter and an AIS MOB beacon on each lifejacket
- Practise heaving-to under pilot so the boat can be stopped fast
Lookout duties under autopilot
COLREGs requires every vessel to keep a proper lookout by sight and hearing at all times. Australian law applies the Collision Regulations to every vessel in Australian waters, and every state's marine safety act carries the same duty. An engaged autopilot changes nothing about that obligation. Investigators into collisions and groundings involving recreational vessels regularly find an autopilot engaged and nobody keeping an effective lookout.
The practical routine on watch is a scan every few minutes: horizon all round, AIS and radar, the chart, the instruments, the sails, the bilge. Then back to the horizon. Fishing boats off NSW and inside the Reef often carry no AIS; whales along the east coast in winter show on nothing.
Off-course, depth and watchkeeping alarms
Set the off-course alarm so the pilot tells you when it cannot hold the heading, which is the first sign of a broken belt, a failing drive or a wind shift. Set cross-track error on a route. Set AIS CPA and TCPA so ships announce themselves. Set a shallow depth alarm. Set a wind-shift alarm when steering to compass under sail. Then confirm the alarms are audible from the bunk.
Manual override in one movement
Every crew member who stands a watch must be able to take the helm instantly: Standby key or clutch lever, then steer. Practise it in daylight with the pilot in every mode, because a pilot in Wind or behaves differently from Auto when disengaged. On hydraulic boats with or , grabbing the wheel is enough; on everything else it is a button or a lever first.
The 3 am test
Manual steering after autopilot failure
Pilots fail from low voltage, broken belts, hydraulic leaks, drive overloads, connector corrosion, lightning and sometimes nothing anyone can diagnose at sea. The plan is simple: hand-steer, reduce sail to make the boat easy, then diagnose. Carry the spares that fit your system: a belt, fuses, a spare drive or pump if you can, and a cockpit tiller pilot in a dry locker if the boat is tiller-steered. A windvane is the ultimate backup on an ocean passage.
Practise hand-steering in a seaway for an hour on a training day. Crews that have never steered the boat without the pilot are the ones that struggle when it stops.
Offshore autopilot drills and crew instruction
Most of this is habit rather than knowledge, and habits are taught. A half-day with an instructor on your own boat covers tether discipline, override drills, alarm settings and a pilot failure exercise, and it changes how a crew behaves for the rest of their sailing lives. It is the cheapest safety equipment aboard.
Questions
Frequently asked
Is it legal to sail with the autopilot engaged and nobody at the helm?
The law requires a proper lookout at all times, not a hand on the wheel. Someone must be keeping watch. An empty cockpit with everyone asleep is a breach of Rule 5 and, in most states, of the marine safety act.
Should a solo sailor sleep with the pilot on?
Solo sailors on long passages do, in short bursts with alarms set, and honest ones acknowledge the lookout compromise. On coastal legs with traffic it is not defensible. Plan solo coastal passages so you arrive before you need to sleep.
What is the best backup for an autopilot offshore?
A windvane on an ocean passage; a spare drive or pump on a coastal passage; a cockpit tiller pilot on a tiller boat. All three are better than none.
Can a wireless remote stop the boat if I fall overboard?
Only if it is on you, in range and you are able to use it, and even then the boat will not come back. Prevention with a tether is the answer; the remote is a convenience.
Practise autopilot operation with an instructor
Habits are learned at the helm with someone watching. The training section explains what a good instructor covers and where to find one in your state.