With the advent of the personal locator beacons (PLBs) and personal AIS units rescue operations are now much easier to perform. We take a look at the best PLBs and AIS on the market and explain the difference between them
Not so long ago simply locating a crew member who had fallen overboard in anything other than the most benign of conditions was a massive challenge, thanks to personal locator beacons (PLBs) and personal AIS units this has fundamentally changed.
PLBs are small devices, typically fitted on a lifejacket, that send a distress message, including GPS position, via satellite to a coastguard operations centre. They therefore work in a similar manner to EPIRBs, but require manual activation and have a shorter operational battery life (usually 24 hours).
A newer type of gadget – personal AIS – both triggers an alarm on board your boat (usually via DSC) and transmits an AIS position that can be seen on your chart plotter and on those of other vessels in a 2-4 mile radius if they are equipped with AIS receivers.
In many situations, personal AIS will therefore be a better bet than a personal locator beacon that only transmits a position to a remote location ashore. Some personal AIS units can also be set to activate automatically when a lifejacket inflates. It’s important to understand the fundamental differences between the two types of device.
What’s the difference between a personal locator beacon and a personal AIS unit?
Personal AIS transmits locally and enables the casualty’s position to be displayed on the chartplotter of your own boat and others nearby, including lifeboats once near the scene.
By contrast, personal locator beacons transmit their primary 406MHz signal only to a remote rescue coordination centre. This can be helpful in raising the alarm and in deploying search and rescue assets, but doesn’t help your own boat and others around you to locate a person in the water.
Personal locator beacons transmit a secondary signal on 121.5MHz, which is helpful for lifeboats homing in on a casualty, but other vessels are rarely equipped to receive this signal. In addition, although the units are generally buoyant, all PLBs need the antennal to be held in the air manually and the body of the unit must be supported out of the water for the GPS antenna to work.
For some time there has been talk of combining both these devices into a single product. There’s no technical reason why that shouldn’t happen, however, there are regulatory hurdles that have yet to be overcome, so it’s unlikely a combined device will be available any time soon.
What’s the best option? Ideally both a personal locator beacon and personal AIS for each crew member – that’s what I have when racing offshore or undertaking long passages when cruising. Don’t underestimate the massive step forward this represents – having both devices all but eliminates the search element of a search and rescue mission. Their adoption therefore ought to become widespread.
If forced to choose only one type, providing my boat was equipped with an AIS receiver, I’d likely plump for the personal AIS, particularly if sailing with other people on board and in an area in which there are generally other boats around.
The best personal locator beacons available right now
N.B. Make sure to check each product is registered for your location before buying.
ACR ResQLink View PLB425 personal locator beacon
Read Yachting World’s ACR ResQLink View personal locator beacon review
This personal locator beacon, unusually, incorporates a small LCD screen which fundamentally improves the user experience.
The PLB425 is supplied with fittings to attach to a lifejacket or to a belt, or around your arm. The estimated battery life is five years.
Alternatively, the ACR ResQLink lower-cost PLB400 without the screen is available from the links below.
RRP: £260 / $299
Note: We may earn a commission when you buy through links on our site, at no extra cost to you. This doesn’t affect our editorial independence.
McMurdo FastFind 220 personal locator beacon
An older model, this personal locator beacon has long been a staple product and can be found on a huge number of vessels around the globe.
The McMurdo FastFind 220 includes all the essential functionality, but without the screen or the ResQLink service of the PLB425.
RRP: £210 / £245
Ocean Signal RescueMe personal locator beacon
This compact product is designed for easy single-handed operation. It’s supplied with fittings for attachment of the personal locator beacon to a belt or to a lifejacket.
The estimated battery life is seven years.
The best personal AIS beacons available right now
Ocean Signal RescueMe MOB1 AIS
This compact personal AIS beacon was introduced in 2015 but remains one of my favourites.
It’s a slim device that fits next to the oral inflation tube of a lifejacket. It can be set to activate automatically when the lifejacket inflates, although this is fiddly to set up and needs to be re-done every time the lifejacket is serviced.
An integrated strobe light helps with the final precision locating of the casualty at night.
RRP: £210 / $290
ACR AISLink MOB Personal Beacon
This is another model that has a choice of manual or automatic activation and includes an ultra-bright LED strobe light.
The battery has a seven year lifespan and an operational life of 24 hours. The unit weighs only 92 grammes.
McMurdo S20 Lifejacket AIS Beacon
As standard this unit has to be activated manually, although if fitted professionally it can be set for automatic activation.
Battery life is again seven years, with 24 hours of continuous operation.
RRP: £175 / $260
This compact model has to be activated manually, rather than being automatically triggered when a lifejacket is inflated.
However, its size and shape mean it can be easily carried by crewmembers even if they are not wearing a lifejacket.