Gear: Electronic Lifesavers

A personal MOB beacon using the AIS system ups the safety factor for sailorsINLINE
Author:
Publish date:
           When you’re in the water, the closest boat to you is the one you’ve just fallen from   

           When you’re in the water, the closest boat to you is the one you’ve just fallen from   

Andrew Taylor was working the foredeck of Derry-Londonderry-Doire, a competitor in the 2014 Clipper Round the World Race, on a stormy day in the Pacific when his worst fears became reality. “At some point, the boat moved pretty dramatically,” Taylor said. “The boat went down, and when it came back up, I wasn’t onboard anymore.”

Taylor survived in the near-freezing Pacific waters and gale force winds for an hour and a half before he was found by his crew and hoisted back aboard. The key factors in his survival were the seamanship of the 65ft yacht’s skipper and crew, the dry suit that kept hypothermia at bay, and—crucially—his AIS man-overboard beacon.

AIS (automatic identification system) is a method of tracking vessels via GPS and sharing this info publicly over certain VHF radio channels. The VHF channels 87B and 88B are reserved for transmitting and receiving digital data. These transmissions are automatically generated and received by dedicated AIS equipment onboard every commercial ship and many recreational vessels. An onboard chartplotter, tablet or computer receives information from this AIS device. When your AIS equipment receives the data from other AIS-equipped vessels, small triangles are placed on your chartplotter screen to indicate where the other vessels are. With such information on your screen, you’ll have greater situational awareness and an increased chance of avoiding collisions. If you’re going to invest in an AIS MOB beacon, you must have an AIS transceiver or receiver installed on the vessel you are sailing on.

AIS is a great safety feature for cruisers, and its usefulness has been expanded by the increasing availability of personal AIS man-overboard beacons—small devices that can be attached to a lifejacket. They receive position data via an internal GPS antenna and transmit that data on the AIS VHF channels to any vessel within range. Upon receiving the signal from your AIS MOB beacon, your AIS-enabled chartplotter (or a smartphone or tablet equipped with an AIS app) should sound an alarm and provide you with the bearing and range to your person overboard—much as the MOB button on your chartplotter does. The difference is that while the plotter’s MOB function will guide you back to the place where you pressed the MOB button, the AIS will point you toward the MOB’s actual location. Bearing in mind that the victim may have drifted a considerable distance from the point where he or she fell overboard, the benefits of a personal AIS beacon are obvious.

           An increasing number of Search and Rescue organizations are equipping their helicopters with AIS to help locate victims   

           An increasing number of Search and Rescue organizations are equipping their helicopters with AIS to help locate victims   

AIS BEACON VS PLB

Many sailors are already familiar with EPIRBs (emergency position indicating radio beacons). A personal locator beacon (PLB) is just a smaller version that you can carry on your person. Like a personal AIS beacon, a PLB can be clipped to a lifejacket and transmits an emergency radio signal containing your GPS position. However, a PLB transmits its emergency signal to satellites that are orbiting the earth. When a satellite receives an emergency radio signal from a PLB or EPIRB, it relays this information to a ground station, which in turn, alerts a search-and-rescue organization, like the Coast Guard. If you’ve just fallen overboard and have activated your PLB, your fate is therefore in the hands of authorities who may be hundreds, or even thousands of miles away. It may be an hour or more before your signal is picked up, and much longer before help arrives. If your shipmates are belowdecks, it may take them a while to realize that a crewmember has fallen overboard, and they certainly will not be aware of your position once you’re out of sight.

An AIS beacon radically increases your chances of survival, since the vessel closest to you is the one you’ve just fallen from.

Choosing an AIS MOB Beacon

I’ve recently reviewed some of the most popular devices on the market. Here are a few of the things you should look for.

First, check out the transmit range. Some manufacturers have listed a transmit range of 4 miles for these beacons, while others have boasted as much as 10 miles. It’s important to remember that these are transmitting over VHF, whose range is line-of-sight. The height of the receiving antenna and the prevailing wave conditions will have a big impact on transmission range.

Then there is the question of DSC (digital selective calling). DSC is a feature built into modern VHF radios that, among other things, allows for private radio calls between vessels. DSC also has a distress feature that, when activated, will trigger an alarm on the radios of all nearby DSC-equipped vessels. Some AIS MOB beacons will trigger a DSC distress call as well. That said, some of this functionality varies by region, and unless you already have one you’ll also need to acquire and enter an MMSI number. So before buying a beacon for its DSC feature, be sure to do your homework.

Summary

Although AIS beacons are currently the only way for an MOB to be directly located by nearby vessels, they are not a complete solution. With worldwide coverage from satellites, PLBs offer direct alerting of rescue services, which will then initiate search-and-rescue operations. Most PLBs also transmit a signal on the 121.5 Mhz emergency aircraft radio frequency. This feature can further aid rescuers in locating the victim.

Considering that PLBs and AIS beacons work on different principles, wise offshore sailors will actually fit their lifejackets with both types of device. Ah, you ask, but why isn’t there a unit that combines the functionality of AIS beacons and PLBs? Perhaps we don’t have much longer to wait. Not yet on the market, but listed as “coming soon,” is the Seaangel SA16+. Nearly identical to the company’s AIS Eco Flare, this device will function as both an AIS beacon and a PLB. Could this two-in-one product be the first of a new generation of lifesaving personal distress beacons? 

SmartFind-S10-AIS-MOB-device_in-hand

McMurdo Smartfind S10

The S10 stands out for its rugged simplicity, with manual activation, an integrated antenna and a waterproof rating down to 180ft. This unit is a little bulky for easy life jacket installation but can be worn on a belt. It is buoyant and when attached to a lanyard you could let it float in front of you. Raising it up by hand may, however, provide a better signal. Its battery is good for five years and will provide enough power to transmit a signal for at least 24 hours.

DSC: No Buoyant: Yes Dimensions: 7.8in x 2in Price: $240 McMurdo, mcmurdogroup.com

McMurdo Smartfind S20

The S20 is a relatively inexpensive, compact unit designed to be fitted to a life jacket. Upon manual activation, a coiled antenna springs from the case and begins transmitting for at least 24 hours. With the unit attached to your inflated life vest tube, the antenna will stand vertically for proper transmission. The battery has a storage life of seven years.

DSC No Buoyant: No Dimensions: 4.7in x 1.1in x 1.6in Price: $190 McMurdo, mcmurdogroup.com

mobDevice

Ocean Signal rescueME MOB1

This neat little unit is one of the more compact devices on the market, which makes it easy to integrate into your inflatable life jacket. In fact, it’s the action of the inflating vest that activates the unit by pulling on its lanyard. It too has a coiled spring antenna. A high-intensity strobe is built in, and the unit will transmit for a minimum of

24 hours.

DSC: Yes Buoyant: No Dimensions: 5.28in x 1.5in Price: $260 Ocean Signal, oceansignal.com

Weatherdock AG easyONE-DSC

This is the only unit that is automatically activated when immersed in water. When a soluble tablet dissolves, it forcefully deploys the coiled antenna. Once activated, the unit is designed to float in front of you while remaining attached via a lanyard. It has a seven-year battery and boasts 36-plus hours of transmit time.

DSC: Yes Buoyant: Yes Dimensions: 6.6in x 1.8in Price: $327 Weatherdock, easyais.com

AISLink MOB

Small but mighty, ACR’s AISLink is an automatically (or manually) activated beacon with a spring antenna, a built-in strobe and a seven-year battery. It can be easily attached to your life jacket, will transmit for a minimum of 24 hours and is waterproof up to 33ft.

DSC: Yes Buoyant: No Dimensions: 4.52in x 1.81in x 1.06in Price: $240 ACR, acrartex.com

AIS-FLARE-Verpackung

Seaangel AIS mob eco FLARE

This small unit from Austrian company Seaangel has an integrated antenna and is automatically activated by the inflation of a lifejacket. Once activated, the unit is designed to be clipped to a small strap (included) that affixes it to your life jacket in such a way that it is positioned with its antenna pointing up. It’s equipped with a five-year battery and boasts astonishing 72-plus hours of transmit time.

DSC: Yes Buoyant: No Dimensions: 2.4in x 1.65in x 1.1in (including antenna) Price: $239 Sea Angel, seaangelusa.com

AIS SARTS

There exists another form of AIS beacon called an AIS search-and-rescue transponder (SART). These are intended to be activated when abandoning ship and are usually used to help locate survivors in a liferaft. Traditionally these devices were called Radar SARTS, and they would transmit a pulse that would then be displayed on the radar screen of a passing ship. AIS SARTS, however, operate on the same principle as an AIS MOB beacon by transmitting your GPS position on the AIS frequencies. They are a larger and heavier than personal AIS MOB beacons, but have increased battery capacity and transmit times exceeding 96 hours.

Phillip Gutowski, a regular contributor to SAIL, owns a Tayana Vancouver 42 and runs BoatRX (boatrx.com), a marine systems installation business. 

Safety & Rescue at Sea
The goal of “Safety and Rescue at Sea” is to prepare captains to be as safe as possible when heading offshore. To be sure, there are plenty of specific tips, but the real value of the course is the philosophy of safety and risk that it imparts. Mario Vittone doesn’t just teach what to think about safety but how to think about it and how to parse risk. This is a course for novices and experienced skippers alike. COURSE BEGINS May 21, 2018.
Sign up today and use the coupon code: SAIL for 15% off.

May 2018

Related

m123728_13_01_171012_PMA_02901_9999

Alicante Announced as an Ocean Race Europe Stop

The Ocean Race Europe, a new event in offshore sailing, will include Alicante as one of four stopover cities. This European offshoot of the former Volvo Ocean Race will include the biggest change to the racing rules under the new title—fully crewed IMOCA 60s will join the ...read more

01-LEAD-doublehanded2

Preparing for a Doublehanded Race

A few months ago we took a look at the development and attraction of doublehanded racing (Two to Tango, June/July 2020). Hopefully, that served to whet your appetite. If so, the question becomes: “How do I get started? The good news, as we explained in Part 1, is that if you are ...read more

01-LEAD-Day-three---dolphins.-300-dpi

A Key Approach to Passagemaking

How you approach offshore sailing is key to the success of each passage. In addition, some of the most valuable, even crucial attitudes and skills may not be either learned or valued in everyday life on shore and may even fly in the face of talents that are greatly admired and ...read more

OceanVoyagesInstitute-2048

Point of SAIL: Mary Crowley of the Ocean Voyages Institute

In this episode of Point of SAIL, Principal Editor Adam Cort talks with Mary Crowley, founder and executive director of the Ocean Voyages Institute, a not-for-profit based in California that has been both educating sailors and working to preserve the health of the world’s ocean ...read more

01-Ocean-Voyages-Institute_PHOTO-READY_1_pg

Tracking and Catching Plastic Waste

Plastic waste—in the form of everything from plastic soda bottles to abandoned fishing nets—constitutes a major threat to the health of the world’s oceans. Giving the immense size of an ocean, though, actually finding all the plastic floating around out there in a time-efficient ...read more

Dreramcatcher -Cate Brown

Marblehead to Halifax Canceled; Alternative Races Planned

The Marblehead to Halifax race that was scheduled for this summer has been canceled due to continuing Covid concerns. Organizers at the Boston Yacht Club and Royal Nova Scotia Yacht Squadron who co-sponsor the event have made the decision because of uncertainty about when the ...read more

SailGP-Team

SailGP Announces Roster and Coach Additions

Athletes Daniela Moroz, CJ Perez and Paul Campbell-James have been added to The United States’ SailGP lineup. Also joining the team will be head coach Philippe Presti. Moroz is a four-time Formula Kite World Champion and two-time U.S. Sailing Rolex Yachtswoman-of-the-Year. ...read more

NEW-westcoastmultihullsmob

Chartering the West Coast

Although two-thirds of the U.S. boating population lives along the Eastern Seaboard, there are many hardy and enthusiastic cruising sailors on the “left coast” as well. Better still, if you’re looking to charter on the Pacific side, there’s plenty of great sailing and many clubs ...read more