Solo Sailing Safety

Solo Sailing · Safety

Solo sailing safety is built on a single premise that experienced singlehanders state plainly and new singlehanders sometimes resist: if you go overboard, you will not be recovered. The boat will continue on its course. There is no one aboard to execute a recovery. No quick-stop maneuver, no throwing of a life ring, no one to call for help on VHF while someone else manages the helm. The water temperature, your ability to re-board, and the sea state will determine the outcome, and none of those variables favor a swimmer in any offshore condition. This is not pessimism. It is the organizing fact of singlehanded safety, and understanding it correctly changes every decision that follows.

The consequence is that solo safety is almost entirely prevention. The gear — jacklines, tethers, PLBs, AIS — is useful and sometimes life-saving, but it operates at the margin. The central discipline is not going overboard. Everything else is what happens after that discipline has already failed.

The Overboard Reality

It is worth being specific about what happens when a singlehander goes overboard, because the vagueness around the subject allows people to maintain a comfortable fiction about recovery. The boat, set on autopilot or windvane, continues on its course. If you are in a tether, you are dragged through the water at the boat's speed — a deeply hazardous situation, but one that at least keeps you connected. If you are not in a tether, the boat sails away.

Water temperature determines survival time. In 15°C water, incapacitation from cold can begin within an hour; in 5°C Southern Ocean water, functional swim time can be minutes. A boat sailing at 6 knots travels one mile every ten minutes. After twenty minutes, the boat is two miles away. In any sea state that would cause someone to go overboard, seeing a swimmer at two miles is not possible without dedicated search, and a boat on autopilot does not search.

The PLB on your person transmits your position to SAR authorities, but the response time for a rescue in offshore waters is measured in hours, not minutes. The PLB is a mechanism for finding your body and notifying your family. Prevention is the only meaningful safety system.

Jacklines: Setup That Actually Works

Jacklines — safety lines running fore-and-aft along the deck to which a tether can be clipped — are standard equipment on any offshore boat. The question is whether they are installed in a way that actually keeps a person on the boat rather than simply attached to it while they dangle over the side.

The critical variable is the position of the jacklines relative to the deck edge. Jacklines installed along the toerail or outboard edge of the sidedecks allow a standard 2-meter tether to reach the water — the sailor clips in, falls over the rail, and is now in the water at the end of a 2-meter line being dragged at boatspeed. This is a serious accident, not a near-miss. The correct installation places jacklines inboard — on the centerline, or as close to it as the deck layout allows. A tether clipped to an inboard jackline and coming taut keeps the sailor on deck or at the rail, not in the water.

The short tether argument: the offshore consensus in recent years has moved toward 1-meter tethers rather than the traditional 2-meter for active work on deck. A 1-meter tether keeps the sailor within arm's reach of the jackline; falling overboard with a 1-meter tether clipped to a centerline jackline means you are at the rail or just over it, not in the water. The 2-meter tether allows more movement along the deck, which is its appeal, but its safety margin is substantially smaller. Many experienced offshore singlehanders use a short tether for active work on deck and a longer tether as a secondary for moving between attachment points.

The Tether Clip Rule

The rule is simple: clip on before you leave the cockpit. Not when you reach the mast. Not when you get to the foredeck and assess whether conditions feel bad enough to warrant it. Before you step out of the cockpit.

The three moments that account for the majority of overboard incidents in solo sailing are sufficiently well-documented to be worth naming directly. The first is the sail change — specifically, going forward in building conditions to handle a headsail or reduce the main, when the boat is moving and the foredeck is wet. The second is going to the bow at any point — to tend the anchor, check the forestay, deal with a furling problem, investigate something at the bow. The third is night passages in deteriorating conditions, when the judgment about whether to clip on is being made at 0200 in building breeze when the boat feels manageable from the cockpit. All three of these situations involve a moment where clipping on feels slightly unnecessary. It never is.

The discipline is a habit, not a judgment call. Clip on before leaving the cockpit. This removes the judgment from the situation and makes it a procedure. Procedures get executed; judgment calls get deferred.

Sleep Management in Shipping Lanes

A large ship traveling at 20 knots covers one mile every three minutes. At that closing speed, a ship at the visible horizon (roughly 5 miles in clear weather) is 15 minutes away from a collision. The 20-minute alarm interval standard in offshore singlehanding is calibrated to this: a 20-minute sleep period allows a maximum closing time of two miles from beyond the horizon before the alarm goes off and the horizon is checked. This assumes clear visibility. In reduced visibility, the margin is smaller.

The system works only if the alarm is reset every time without exception. The failure mode is falling into a longer sleep after the alarm goes off — convincing yourself it is safe to sleep "just another 20 minutes" without resetting. This is how extended sleep periods happen. The discipline is to get up, check the horizon and the AIS display, and reset the alarm before doing anything else.

AIS watch alarms — available on any chartplotter with AIS integration — set a guard zone around the boat and alert when any AIS target enters it. A 6-mile guard zone gives approximately 18 minutes of warning for a ship traveling at 20 knots. Combined with the 20-minute sleep alarm, this provides overlapping protection. The gap is vessels that do not carry AIS: fishing boats, small commercial craft, and some vessels in coastal waters. Radar with a guard zone closes some of this gap; there is no system that closes all of it. The combination of AIS alarm, interval alarm, and the discipline of actually getting up when both go off is the practical offshore standard.

Radar Reflectors and AIS Transponders

A passive radar reflector — the folded-aluminum octahedral type mounted in the rigging — reflects radar energy back toward ships that illuminate the boat. The performance of passive reflectors in real-world conditions has been studied and found to be significantly worse than manufacturers claim, particularly in angles-of-heel relevant to a sailing yacht, and particularly with the increasing use of solid-state radar systems that process returns differently than older magnetron types.

A Class B AIS transponder is the offshore minimum standard for a singlehanded boat. It transmits the boat's position, course, and speed every 30 seconds to all AIS-equipped vessels within range (typically 20–30 miles) and displays the same information about surrounding traffic. This changes the solo sailor's collision avoidance picture entirely: instead of relying on a ship's radar operator to notice a small target, the ship's ARPA system automatically tracks and alerts on any AIS target on a collision course. Many modern cargo ships operate with minimal bridge watch; the automated systems are what will generate an alarm for your approach.

Active radar reflectors — which generate a powered return rather than a passive one — offer substantially better detection performance than passive types and are worth considering for offshore passages. They are a supplement to AIS, not a substitute for it.

PLB on Your Person

A Personal Locator Beacon worn on the body is fundamentally different from an EPIRB in the grab bag or mounted in the companionway. The EPIRB on the boat activates when the boat sinks or is manually triggered. If you are in the water and the boat is sailing away, neither of those conditions has been met. The PLB on your person activates when you activate it, or when it is immersed (for the hydrostatic release models), and it transmits your position — not the boat's position — to COSPAS-SARSAT.

The correct wear position is on the person at all times when offshore, integrated into the sailing jacket or harness so that it is present in the moment of entering the water, not left below while you go forward for "just a quick" repair. The argument that a PLB is uncomfortable or inconvenient to wear continuously is the argument that most singlehanders abandon after their first serious offshore passage, when the cost-benefit calculation becomes vivid.

Emergency Procedures and the Grab Bag

The grab bag is the emergency kit that goes with you if you have to abandon ship. It should be within arm's reach of the companionway at all times offshore — not in a dedicated locker at the stern, not stored below with the spares. The companionway is where you will be when you need it; it is also the point from which you can reach it in a single step if the boat is flooding or on fire.

Standard grab bag contents for offshore: the EPIRB (if not the fixed type), flares, water, food for 24–72 hours, a knife, a signal mirror, a handheld VHF, a handheld GPS (with batteries separate from the main system), copies of ship's papers and your passport, cash, and any critical medications. Weight and volume limit what goes in; prioritize the signaling equipment and the EPIRB above everything else.

VHF Channel 16 is the international distress and calling frequency — transmit a MAYDAY call on 16 if you have the ability. An EPIRB activation notifies the COSPAS-SARSAT system automatically and generates a SAR response. The two systems work independently; activating both increases the probability that the response is correctly coordinated. The liferaft, if carried, goes with the grab bag; most offshore singlehanders on smaller boats carry an inflatable coastal lifejacket rather than a full offshore liferaft, on the basis that the liferaft is useless unless you can get into it from the water, which requires preparation and is substantially harder than it appears in calm conditions.

← Solo Sailing Hub  |  Passage Preparation →

Frequently Asked Questions

Why is the singlehanded overboard scenario treated as essentially unrecoverable? When a singlehander goes overboard, the boat continues on autopilot or windvane course — there is no one aboard to execute a recovery maneuver, throw a life ring, or call for help while managing the helm. A boat sailing at 6 knots travels one mile every ten minutes; after twenty minutes the boat is two miles away and a swimmer cannot be seen without dedicated search. Water temperature determines survival time: in 15°C water incapacitation can begin within an hour; in 5°C Southern Ocean conditions functional swim time can be minutes. The PLB on your person transmits position to SAR authorities but response time offshore is measured in hours. Prevention is the only meaningful safety system.

What is the correct jackline installation and why does outboard placement fail? Jacklines installed along the toerail or outboard edge of sidedecks allow a standard 2-meter tether to reach the water — the sailor clips in, falls over the rail, and is dragged through the water at boat speed. The correct installation places jacklines inboard, on the centerline or as close to it as the deck layout allows. A tether clipped to an inboard jackline that comes taut keeps the sailor on deck or at the rail, not in the water. The offshore consensus has also moved toward 1-meter tethers rather than 2-meter for active deck work, keeping the sailor within arm's reach of the jackline on any fall.

What are the three moments that account for most overboard incidents in solo sailing? The first is the sail change — specifically going forward in building conditions to handle a headsail or reduce the main when the foredeck is wet and the boat is moving. The second is going to the bow for any reason: anchor work, forestay inspection, furling problems, or bow investigation. The third is night passages in deteriorating conditions, when the judgment about whether to clip on is made at 0200 in building breeze when the boat feels manageable from the cockpit. All three share the same feature: a moment where clipping on feels slightly unnecessary. The discipline is to make it a procedure rather than a judgment call — clip on before leaving the cockpit, every time.

Why is a Class B AIS transponder the offshore minimum standard for singlehanders? A passive radar reflector's real-world performance has been found to be significantly worse than manufacturer claims — particularly at sailing angles of heel and with the increasing use of solid-state radar systems. A Class B AIS transponder transmits the boat's position, course, and speed every 30 seconds to all AIS-equipped vessels within 20 to 30 miles and displays surrounding traffic. Many modern cargo ships operate with minimal bridge watch; the ship's automated ARPA system tracks AIS targets and generates collision alerts automatically. This changes the collision avoidance picture from relying on a radar operator noticing a small return to automatic tracking of any AIS target on a collision course.

Why must a PLB be worn on the person rather than stored in the grab bag? An EPIRB in the grab bag or mounted at the companionway activates when the boat sinks or is manually triggered. If the singlehander is in the water and the boat is sailing away, neither condition has been met. The PLB on the body activates when the sailor activates it, or on immersion for hydrostatic release models, and transmits the sailor's position — not the boat's. The correct wear position is integrated into the sailing jacket or harness at all times offshore. The argument that a PLB is uncomfortable to wear continuously is one most singlehanders abandon after their first serious offshore passage.

How does the 20-minute sleep alarm work and what is the failure mode? A large ship at 20 knots covers one mile every three minutes. A ship at the visible horizon approximately 5 miles away is 15 minutes from a collision — the 20-minute interval allows a maximum closing time of two miles from beyond the horizon before the check. The system works only if the alarm is reset every time without exception. The failure mode is falling into longer sleep after the alarm, convincing yourself it is safe to sleep another 20 minutes without resetting. The discipline is to get up, check the horizon and AIS display, and reset before doing anything else. AIS watch alarms with a 6-mile guard zone provide overlapping protection for AIS-equipped vessels.