When you hear the cry of “Man Overboard!” on a ship, it’s an emergency situation. The sea is unkind to those that fall from their vessel, and survival is never guaranteed—even in the most favorable conditions. Raging swell and the dark of night can only make rescue more impossible.

Over the centuries, naval tradition has included techniques to find and recover the person in the water as quickly and safely as possible. These days, though, technology is playing an ever-greater role in such circumstances. Modern man-overboard (MOB) systems are designed to give crews of modern vessels a fighting chance when rescuing those in peril.

A Hard Task

Man overboard recoveries are challenging to execute, because of the unpredictable and rapidly changing conditions at sea. Once a person enters the water, factors like strong currents, wind, waves, and darkness can make it difficult to keep them in sight and quickly maneuver the vessel to their location. Even in calm weather, a victim can be carried away faster than it appears, and thick clothing or heavy gear may limit their mobility, reducing their ability to stay afloat or attract attention. Additionally, communication can be hindered by engine noise, onboard confusion, or the sheer panic of the moment. All of these elements combine to make man overboard scenarios both time-sensitive and complex operations for the crew.

These situations can pose particular difficulties for larger ships. Where a smaller craft might be able to quickly stop to recover a fallen crew member or passenger, larger vessels are much slower to maneuver. Traditional man overboard techniques, such as having crew members point at the victim in the water, can fail to work if the vessel drifts out of visual range. Smaller vessels can have problems, too. With smaller crews, it can be difficult to bring someone back on board while also ensuring the vessel is maneuvered safely.

Man-overboard systems aim to help improve the likelihood of survival for those that fall into the water. They come in a variety of forms designed to suit different types of vessel, and the different scenarios they operate in.

For small boats, the most basic systems act as simple alarms, which automatically sound when a person falls overboard. These use small wireless fobs or wrist straps, which communicate with a base station on the boat itself. If the short-range radio link between the two is severed, an alarm is sounded, notifying those on board of the man overboard situation. Many models also feature a water immersion sensor, so the alarm can be raised instantly if someone falls into the sea. For small boats operated by individuals, this can be very useful. There is great benefit in receiving an automatic notification if someone falls into the water, even if nobody on the boat notices the incident directly.

Many of these small-scale systems are also set up to work with smartphones or tablets. They instantly log the position at which the man overboard event occurred, and guide the vessel back to the victim in the water. Soem even come with a special “captain’s fob” wherein the system will cut the boat’s engines in the case the skipper falls overboard. This can be valuable for avoiding a runaway boat scenario.

These systems are useful for small boats. When it comes to larger vessels like cruise ships, however, the solutions are more advanced.  When duly equipped with a man overboard system, these craft are dotted with sensor packages, including cameras, thermal imagers, and LIDAR scanners, all of which are trained on the perimeter of the vessel. These are set up to detect if a human falls overboard, at which point they raise the alarm. The bridge is notified as to the emergency, and the vessel receives directions to the area where the person fell from the ship.

These systems come with additional benefits, too. The sensors that detect a fall can also be used to track a person’s motion in the water. Essentially acting as a high-tech surveillance system trained on the perimeter of the vessel, they can be used to detect unwelcome boarders trying to gain access to the ship as well. They can also detect if someone might be climbing on the side of the ship—a foolish act that is perhaps likely to precede a fall into the water.  Indeed, it’s pretty hard to fall off of most cruise ships—the high railings are designed specifically to prevent that. Misadventure plays a role in a significant proportion of man overboard incidents on cruises.

This technology is relatively new. It has largely been developed as a result of the The Cruise Vessel Security and Safety Act of 2010, which stated that cruise vessels “shell integrate technology that can be used for capturing images of passengers or detecting passengers who have fallen overboard, to the extent that such technology is available.” At the time, advanced man overboard systems did not exist, so the requirement was effectively optional. As covered by USA Today, workable systems have been developed, but they are not yet ubiquitous, as many cruise lines are yet to deploy them across their fleets. An increasing number of vessels are now sailing with such equipment, though MARSS notes that less than 2% of cruise ships are currently fielding effective systems.

The fact remains that falling overboard from a ship is a fraught situation. Statistics from 2018 indicate that of the 1 or 2 people that fell from cruise ships each month, just 17 to 25% were rescued. The hope is that these automated systems will speed responsiveness to man overboard events, and lead to better outcomes. Indeed, in many cases, crews only respond to man overboard incidents hours after victims fall into the water, when the alarm is raised by concerned fellow travelers. This can make even just finding the individual near-impossible. Automated systems have the potential to cut response times to minutes or better, greatly increasing the chances of spotting a person in the water and executing their rescue.

Ultimately, the advancement of automated detection and response systems offers a clear path to improved safety on vessels small and large alike. By sharply cutting the time to raise an alarm, these technologies can dramatically improve the odds of saving a life. As more vessels adopt these systems and integrate them into their safety protocols, we stand to shift the balance, turning dire emergencies into manageable situations, and ultimately, safeguarding more passengers and crew at sea.