Man Overboard — Prevention and Recovery
Getting back to someone in the water is harder than it looks in calm conditions. In rough conditions, it is brutally difficult.
Prevention
The best MOB drill is the one you never have to run for real. Every piece of safety gear, every protocol, every piece of rigging exists to keep people on the boat.
Jacklines run fore-and-aft from cockpit to bow on both sides. They should be webbing, not wire — wire rolls underfoot and causes the fall you're trying to prevent. Rig them before you leave port. Clip in before you leave the cockpit. This is a rule, not a suggestion.
Tethers and harnesses must fit the wearer. A tether longer than 2 metres allows a person to fall far enough to be dragged underwater before the boat can be stopped. Use a short tether — under 2 metres — or an inertia-reel that locks under load. The attachment point matters: clip to a strong point on the jackline or a dedicated pad eye, never to a lifeline stanchion.
The rule of one hand for the boat: one hand always grips the boat or a fixed structure. Moving on deck in a seaway with both hands occupied is how people go over.
Lifelines are a last resort, not a primary safety system. Check stanchion bases regularly — they corrode from below, and a stanchion that feels solid can pull out under a sudden load. Check lifeline tensioners and swage fittings before every offshore passage.
Night passages require clipping in the moment you leave the companionway, even in calm conditions. Disorientation, fatigue, and darkness remove the margin that daylight provides. Going forward unclipped offshore at any time, day or night, is not acceptable practice.
Before every offshore passage, have each crew member put on their harness and tether and clip to the jackline. Make it routine — it will feel normal when conditions deteriorate.
A tether longer than 2 metres can allow a person to be dragged underwater at boat speed before the vessel can be stopped. Short tethers only.
Why are webbing jacklines preferred over wire jacklines?
Immediate Response
The first 60 seconds after someone goes overboard determine whether you bring them back. Everything that happens in those 60 seconds must be automatic — drilled, not thought through.
Shout 'MAN OVERBOARD' loudly and repeatedly. Everyone on the boat needs to know immediately. Assign one person — not the helmsman — to do nothing but watch the person in the water. That person points at the casualty continuously and never looks away for any reason. Losing sight is losing the person.
Throw the horseshoe buoy and danbuoy immediately — don't wait to see if they need it. Every boat should have these rigged for instant deployment, not clipped down with multiple fastenings. The danbuoy marks the position with a flag; the horseshoe gives the casualty something to hold. Throw them even if the person is a strong swimmer.
Press the GPS MOB button the instant someone goes over. On most chartplotters this is a dedicated button or long-press. It records the exact position and gives you a bearing and distance back. Even if you can see the person, that position becomes critical if you lose sight of them.
If there is any doubt about recovery capability — short-handed crew, rough conditions, injured or unconscious casualty — declare MAYDAY immediately on VHF channel 16. Do not wait until you have failed to recover them. Other vessels and rescue services need maximum time to respond.
Throw anything that floats toward the casualty: fenders, life rings, anything that gives them something to grab or marks the position. Every second they are in the water in cold temperatures, their ability to help themselves diminishes.
Designate crew roles for MOB before you leave the dock. Everyone knows: who shouts, who watches, who throws the buoy, who handles the GPS. Drilled responses beat improvised ones every time.
Do not let the person watching the casualty leave their post for any reason. In a seaway, a person in the water can disappear from sight in seconds behind a wave. Once lost visually, recovery becomes a search operation.
What is the designated spotter's only job during a MOB event?
Recovery Maneuvers
There is no single universally correct recovery maneuver. The right choice depends on wind strength, sea state, crew number, and whether the casualty is conscious and able to assist. Know at least two methods and drill them.
The Figure-of-Eight (Reach-Tack-Reach) is the most reliable under sail for trained crews. It uses the boat's sailing characteristics and brings you back to the MOB position on a controlled approach under control.
The Quick-Stop is better for short-handed crews because it keeps the MOB in sight throughout. Immediately heave-to, then tack short, maneuver to approach the casualty.
Under power, approach from downwind so the boat drifts down toward the casualty rather than away. Come to a stop with the person alongside. The most critical rule under power: STOP THE ENGINE before the casualty reaches the propeller. A running propeller will kill or maim. Shift to neutral well before they reach the stern.
Practice both maneuvers with a fender as a stand-in for the casualty. Knowing the theory is not the same as having done it.
In rough conditions, a controlled approach under sail may be safer than under power because you have more precise speed control. Know your boat.
For the Quick-Stop: the moment someone goes over, put the helm hard over toward them and heave-to. The boat slows and you never lose sight of the casualty. From there, motor or sail back in a tight circle.
Under power, shift to neutral and stop the engine before the casualty reaches the propeller. This is non-negotiable. A turning propeller is lethal.
When should you stop the engine during a powered MOB recovery approach?
Recovering the Casualty Aboard
Getting alongside is only half the problem. Lifting a waterlogged, exhausted, possibly hypothermic or injured person out of the water and over the rail is physically demanding work — more so than most crews expect until they try it.
A person fully clothed with soaked foul-weather gear and sea boots can weigh 50 kg more than their dry weight. You will not lift them over the rail by gripping their arms. You need mechanical advantage.
A halyard led through a snatch block and back to a winch gives you lifting power. A loop of line or a dedicated MOB sling placed under the casualty's armpits allows a controlled lift. If the boom vang or main halyard can be rigged to hoist, use them.
A swim step or boarding ladder at the stern is easier than lifting over the rail amidships. Many modern boats have these — know where yours is and how to deploy it. A casualty who is conscious and not injured may be able to climb a ladder with assistance.
The MOB sling (a dedicated piece of gear, often a loop of webbing with a spreader bar) is the most reliable tool for the job. It is designed to support a casualty under their arms and between their legs for a controlled vertical lift. Every bluewater boat should carry one.
If the casualty is unconscious, do not try to bend them over the rail headfirst. This can cause additional injury and may compromise their airway. Rig a horizontal lift using a halyard and sling and bring them aboard as flat as possible. Have someone on the boat prepared to begin CPR the moment they are clear of the water.
After recovery, treat for hypothermia regardless of water temperature — remove wet clothing, insulate, and monitor. Even in warm water, exhaustion and shock reduce core temperature.
Practice the recovery with a willing crew member before you need it. Rig the halyard and sling while they sit on a dock or swim step. Discover the problems before they are problems.
Do not attempt to recover an unconscious casualty by bending them headfirst over the rail. Use a horizontal sling lift to avoid spinal injury and maintain their airway. Have CPR ready to begin immediately on recovery.
What is the most effective method for lifting a waterlogged, exhausted casualty aboard?
Summary
Clip in before leaving the cockpit — jacklines fore-and-aft, short tether under 2 metres, no exceptions offshore or at night.
On MOB: shout, assign a dedicated spotter who never looks away, throw the horseshoe buoy and danbuoy, press GPS MOB, and call MAYDAY if in any doubt.
The first 60 seconds are decisive — every crew member must know their role before it happens.
Under power, stop the engine before the casualty reaches the propeller — a spinning propeller is lethal.
Recovery is harder than the approach — use a halyard, winch, and MOB sling for mechanical advantage; never lift an unconscious person headfirst over the rail.
Drill MOB procedures with your actual crew in calm conditions — the body executes what the brain has practiced.
Key Terms
- Jackline
- A line or webbing strap rigged fore-and-aft on deck to which a safety tether is clipped, allowing crew to move along the deck while remaining attached to the boat.
- Inertia-Reel Tether
- A safety tether that pays out freely during normal movement but locks under sudden load, functioning similarly to a car seatbelt.
- Danbuoy
- A tall floating pole with a flag and often a light, thrown at the MOB position to mark it visually.
- Figure-of-Eight Recovery
- A sailing MOB recovery maneuver that uses a broad reach, tack, and close-reach approach to return to the casualty in a controlled manner.
- Quick-Stop
- A MOB recovery maneuver where the boat immediately heave-tos to keep the casualty in sight, then maneuvers back in a tight circle.
- MOB Sling
- A dedicated webbing sling with a spreader bar designed to be placed under a casualty's armpits and between the legs for a safe, controlled vertical lift out of the water.
- Heave-To
- A sail trim configuration where the backed headsail and centered or slightly eased main cause the boat to lie nearly stopped, drifting slowly to leeward.
Man Overboard — Final Assessment
What is the maximum recommended tether length for offshore sailing?
Immediately after someone falls overboard, the designated spotter must:
During a powered MOB recovery, when must the engine be stopped?
Why are webbing jacklines preferred over wire jacklines?
An unconscious casualty is alongside the boat. What is the correct way to bring them aboard?
References & Resources
Related Links
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US Sailing MOB Recovery Guide
Detailed guidance on MOB prevention, maneuvers, and recovery equipment from US Sailing.
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Ocean Safety — MOB Equipment
MOB slings, danbuoys, horseshoe buoys, and deck hardware for offshore safety.
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RYA Man Overboard Techniques
RYA guidance on MOB maneuvers and crew training requirements.