Man overboard



Man overboard refers to a situation in which a person has fallen off a boat or ship into the water, and is in need of rescue. Whoever sees the person fall should shout "MAN OVERBOARD" to alert other crew members, and attempt to maintain visual contact with the person in the water.

Causes
A person may fall overboard for many reasons: they might have been struck by a spar of the ship (boom, spinnaker pole, davit), or might have lost their footing due to a slippery deck or the unexpected movement of the boat.

Rescue
The guiding principle is to stop the boat or slow it, if stopping is impossible and immediately marking the location by tossing a PFD or Man Overboard Pole into the water. This is naturally achieved on a sailing boat if the helmsman releases the tiller and dumps the mainsheet so slowing dramatically.

A better approach is heaving to. Again this will occur naturally if the helmsman pushes the tiller to leeward immediately and ignores the jib-sheets. He also dumps the mainsheet at the same time. (Spinnaker guy also dumped if applicable). The sailing boat will tend to come up to weather and the jib will back. When this backing happens, the tiller must be reversed to point towards the boom. The boat is now hove-to and sensibly close to the MOB. - At this stage the mainsail is loose and flapping and the jib is backed (or spinnaker floging) and the yacht is now nearly stopped and it is just scant seconds since the loss overboard. (A wheel steered boat would move the wheel to bring the yacht towards the wind and when the jib backs he reverses the wheel rotation promptly, while also dumping the mainsheet.)

This should be an instinctive reaction of all helmsmen. It works on all points of sailing. At that stage the launching of LifeSling can be accomplished by the helmsman, unless another crew member has previously done so. With a bit of luck the yacht will be within the range of the cordage on the recovery apparatus. A life preserver should be thrown to the person in the water to aid them and to assist in returning to the location of the fall. At least one crew member, usually the one who spotted the person fall, should be designated to point constantly at the person in the water while the rest of the crew bring the boat to the position for recovering them. Then a line may be thrown to them once the boat is in position and any propellers are stopped.

If the person is unconscious they will need to be lifted into the boat. Many people are also not strong enough, especially in wet clothing, to lift themselves back on board and will also need assistance.

Technology
Activation of the MOB button on an onboard GPS receiver will pinpoint the position of the loss, to which the yacht can be maneuvered if visual contact with the MOB is lost.

Man overboard systems that can detect a man-overboard incident and automatically mark the location are said to be in development, but nothing is on the market as of September 2007. Such a system might involve a combination of sonar and GPS sensors to detect and track MOB incidents. This could require that each crew member wears an identification device that transmits a digitally coded sonar signal when submerged. Within the hull of the boat a hydrophone could detect the signal and the MOB's impact point is stored via the internal GPS and visual and audible alarms are raised at the helm. LEDs at the helm guide the helmsman back to the original impact point.