Man Overboard Alerts

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.
See posts with no answers
Jmreim

Jmreim

Senior Member
Joined
Jan 7, 2019
Messages
179
Location
USA
Vessel Name
Boundless
Vessel Make
2013 North Pacific 43'
In addition to MOB apps that are built into integrated navigation systems from Simrad, Garmin, Raymarine and others, there are a number of wearable devices on the market specifically designed to alert crew members of a man, woman, child or pet who has fallen overboard. If anyone has experience with these systems, it would be very helpful to learn more about them.

There may also be existing wearable devices that are already widely used for other applications but could be useful for man overboard situations. Fall Detection on an Apple Watch comes to mind but not sure if it can be water activated.

Thx -
Jim
 
I don't have experience with those systems, but what I do know is that finding the person is one problem (the search in SAR) and getting the person back on board is a complete different ball game (the rescue in SAR).

We are with 2 on our boat, my wife weighs 110 lbs and I weigh 185 lbs, but when I go overboard it would be near impossible for her to get me back on the boat. If I would be conscious and could help it would not be a problem, but if I would be unconscious then we can forget about it, she won't be able.

After we came to that conclusion I installed a hoist system, with a hook that can be attached to a sort of sling. The only thing she needs to do now is to get the sling around my arms, behind my back, hook it up and hoist me up. We have tried it, can't say it is comfortable, but it works, she was able to get me high enough so she could pull me inside the boat.
But then again, we practiced during calm weather and that is normally not the time you go overboard. Have not tried it during heavy weather, with a rolling boat, that could become a completely different story. Perhaps one day we will give it a try, after all........I will be the one in the water. :)

Last summer a water taxi was overrun by another boat and the whole thing was on video. People on other boats were unable to lift the survivors out of the water. The survivors were conscious, hanging on the side of the boat, but nobody could actually get them onboard.
So that part of SAR needs some attention.

If anyone knows a good, functioning system I am all ears.
 
All good points and important considerations - thx.
I’m just starting at the front end of a MOB event - if our dog (or 1 of us) falls in unnoticed, the odds of a happy ending drop significantly, regardless of a reliable extraction plan.
 
I just purchased but have not yet installed an MOB+ engine cutout switch. It pairs with a fob that activates on contact with water. My primary use case is for one-handing, which I do a fair amount of, positioning the boat ahead for wife and family to join and such. I have a mental movie of going over the side when stepping out the pilot house door to attend to something on deck while the boat is on autopilot and watching it chug off into the distance. I plan to zip it into my PFD, which also has an inflation activated AIS beacon and strobe looped in. But it can also be worn on a bracelet by a child or a collar by a pet.
 
Looks like the ticket for couples' MoB "Search" and find (good explanation Mambo) is a new compact PLB with AIS (PLB = Personal Locator Beacon, normally EPIRB). Presumably with AIS you could return to the MoB location via chartplotter.

https://www.milltechmarine.com/acr-2933

Sounds intriguing - for $1k/pair, within range of feasibility for a cruising couple.

Peter
 
I bought Spinlock AIS MOB1 for my wife and I. I have yet to go through the test procedure and reassure myself that it works as advertised. I tell my wife to tell me when she goes outside and I'm at the helm. Freaks me out to turn around and she's not in the cabin. If they work as advertised and she went over, I would get a MOB notice with waypoint on my display.

As to rescuing each other in a MOB situation, I have a Novalift that would get a person onboard. But most important is a throw line with a carabiner for the MOB to clip to themselves. Once tethered to the boat, even if she couldn't get me in she could radio for help and keep track of my hypothermic body.

I decided against the automatic cutoff fob and don't think it would be of much use. I've counted a few seconds, turned the engine off, and seen how far the boat would be from me if I fell over. Assuming no wind, no current, and I was in a wet suit with fins on, I might be able to swim to the boat but probably couldn't get back on. Better the boat run aground and people see that there is nobody aboard. That would get a SAR going before I was likely to swim to the boat or ashore.
 
Marco Flamingo said:
Better the boat run aground and people see that there is nobody aboard. That would get a SAR going before I was likely to swim to the boat or ashore.
Click to expand...

Swimming ability aside, I’m not sure that other boaters or dock owners in the path of travel would feel the same way.
 
Marco Flamingo said:
I bought Spinlock AIS MOB1 for my wife and I. I have yet to go through the test procedure and reassure myself that it works as advertised. I tell my wife to tell me when she goes outside and I'm at the helm. Freaks me out to turn around and she's not in the cabin. If they work as advertised and she went over, I would get a MOB notice with waypoint on my display.

As to rescuing each other in a MOB situation, I have a Novalift that would get a person onboard. But most important is a throw line with a carabiner for the MOB to clip to themselves. Once tethered to the boat, even if she couldn't get me in she could radio for help and keep track of my hypothermic body.

I decided against the automatic cutoff fob and don't think it would be of much use. I've counted a few seconds, turned the engine off, and seen how far the boat would be from me if I fell over. Assuming no wind, no current, and I was in a wet suit with fins on, I might be able to swim to the boat but probably couldn't get back on. Better the boat run aground and people see that there is nobody aboard. That would get a SAR going before I was likely to swim to the boat or ashore.
Click to expand...

A lot of boats have swim ladders that are deployable from the water, and I always thought that was a good feature. Does your boat not have one? Not helpful when you are unconscious but it might be helpful to someone on board trying to get a line on you.
 
When I was a presented at Trawler Fests, I used to do a MoB recovery demo dockside (well, with Chuck Hawley from West Marine). I'd pick the biggest guy in the crowd who would don a gumby suit snd jump in the water. Then I'd find the tiniest woman. Using a 5-part Lifesling lifting tackle, she could easily lift the guy. Audience was impressed (so was I- I own both a lifesling and their expensive 5-part lifting tackle)

A few lessons learned:

1. If the MoB is unconscious, you're screwed. Best option is probably to secure to side of boat and wait for help. Rarely is putting a second person in the water a good idea.

2. Many/most boats don't have great lifting points. And few have ability to lift the MoB high enough. You gotta practice

3. Assuming the woman is the reluctant partner, doing stuff like MoB really builds confidence and makes them more comfortable with boating as a couple (Venus and Mars thing).

4. Swim grids, being at end of boat, are pretty dangerous for the MoB in any wave action. Best to board the MoB somewhere midships, on the lee side.

Peter
 
Last edited:
Check out using a tarp or net and "parbuckling". You can get an unconscious person aboard.
 
I have found that the best MOB alert is the loud splash on impact :)

That said, I have a boom on my top deck with a 7:1 block and tackle plus an electric winch. This is adequate for retrieving a MoB. However, I will also install a ladder off the swim platform that can be deployed if needed. This would not be the preferred extraction point because the MoB could be hit by the swim platform in wavy conditions whereas a side exit would just be the roll.
 
Last edited:
We conduct mock "man overboard" drills on my boat several times a summer.

They go like this. "OK I fall overboard, what do you do"?

The Admiral has it down pretty well.

pete
 
I think one of the disadvantages of an MOB1 type AIS beacon for a dog is that most (maybe all?) of them require manual activation. So you would have to teach your dog how to read the directions, operate the safety latches, deploy the antenna, etc. Depending on the breed of dog, that could be difficult.

Other devices, like the Raymarine MOB and similar, have a tag that is constantly polled by an onboard transceiver with a very limited range. If it loses contact with a tag, it alarms and sends an MOB signal to the chart plotter, which alarms, places a MOB waypoint at the point of discovery, and set the goto to that waypoint. It is not updated as it would be with an AIS MOB beacon, but at least you know and know where to start looking. This would work with a dog, as it doesn't need to know how to read.
 
I began this thread b/c the initial alert is the most interesting (and IMO important) piece of finding/saving a MOB. There don't seem to be many great choices but the AIS option appears to be the most reliable and accurate since the MOB will show on your MFD.
 
Jmreim said:
I began this thread b/c the initial alert is the most interesting (and IMO important) piece of finding/saving a MOB. There don't seem to be many great choices but the AIS option appears to be the most reliable and accurate since the MOB will show on your MFD.
Click to expand...

If you're able to react immediately to an alarm finding the MOB shouldn't be that difficult, especially if the victim is wearing a pfd with light and whistle.

What's your objection to wearable Bluetooth solutions? I have an ACR Olas system that I'm confident will do what it claims to do. There are a range of options using similar technology.

I've been on offshore sailboats where everyone has AIS transponders, because the boat can travel a long way before being able to execute a retrieval. But for a rec trawler the simple fob seems to me to be suitable. You can keep a dozen aboard and put them on pets and guests.
 
Actually happy to hear from someone who has (uses?) ACR OLAS - I've seen several Bluetooth device reviews that find them quite unreliable. Have you actually had success testing OLAS? Thx for the input.
 
I bought it last year and powered it up, but have yet to complete the installation. So no real world experience. My intended usage is as a wireless kill switch.

My research when I made the purchase decision made me consider the case of a false alert - my boat is pretty big for a single base station - but I'm willing to live with that risk. But I've never doubted that the alarm would trigger if I went overboard. Always happy to be educated if you have updated info.

See also https://www.trawlerforum.com/forums/showthread.php?t=63045

Edit: guess I've had it for two years. Time flies! https://www.trawlerforum.com/forums/showthread.php?t=58632
 
Last edited:
No updated info - just random anecdotes & hearsay.
We coastal cruise @ 7 kts - my primary objective is being alerted when a person or pup goes overboard - obviously, can’t find/retrieve them quickly without an alert.
 
Gotcha. The wearable tags all work the same way AFAIK. Their only job is to maintain a regular Bluetooth connection with a base station. The alert goes off when the base station loses contact. It's a simple reliable failsafe solution using established technology.

Pick your base station. It could be your MFD, a piece of dedicated hardware, or a smart phone or tablet. They all work the same way. On a bigger boat a second antenna may be necessary to prevent false alarms.
 
We have gone with the Ocean Signal PLBs which use AIS. They are set to turn on when the lifejacket inflates. The person in the water should be in range when the other of us notices that they are alone. Concern about Bluetooth systems was their limited range. AIS is also visible to other boaters. For the Rescue part we have a Lifesling and a 5:1 tackle that is rigged from the overhead near the side entrance gate. For self-rescue there is a ladder deployable by the person in the water.
 
Part of our "man overboard" training is to activate the man overboard button on the GPS but since the Admiral is not real well trained on the GPS I think other parts of the drill are more important, like turning off auto pilot, throwing floatable things overboard, including the life ring and starting the "sweep".

pete
 
My experience has been if you have a POB in anything but very calm seas, an electronic assist may be by far your best bet. At night with a strobe or decent MOB light can actually make it easier to locate the MOB than in daylight without electronics.

For those just using PLBs, if you have satellite or other comms with the USCG, they may be able to send you a position rather quickly if the PLB is GPS equipped.

Again experience has taught me, if you don't locate a MOB without light at night or electronic aid in the day within minutes, often you won't.
 
As has been said, the issues are twofold. Locating the MOB and getting them on board.

On Play d'eau, we had MOB1 in our lifejackets, for AIS alerts on our NN3D.

To retrieve the MOB, we could use the transom's boarding ladder, or a Marcus MOB emergency ladder. Far easier to roll someone on board when they are horizontal than vertical.
 
Marco Flamingo said:
I bought Spinlock AIS MOB1 for my wife and I. I have yet to go through the test procedure and reassure myself that it works as advertised. I tell my wife to tell me when she goes outside and I'm at the helm. Freaks me out to turn around and she's not in the cabin.
Click to expand...

I'm always trying to remain aware of my wifes (and other passengers) location. When she leaves from the flybridge, I will look behind me to make sure she's not swimming in the wake. Often times I'll leave the helm to go below and check on her. Not that shes not a capable person but I consider myself a prudent mariner...and a caring husband.
Our current boat is a double cabin design, which is the all time worst/most dangerous design ever ,IMO, when it comes to ascending & descending to & from the flybridge station.
Regarding the alert gizmos, it's doubtful we'll ever employ one. Realistically, I'm not going to take the time to put the thing on or bring it with me. If conditions are bad, I'm going to hang on to the railings like a cat walking a clothesline and be extra careful and insist my wife does the same. I really don't want an engine cutoff thing incorporated into the system. It's one more thing to potentially go wrong with the electrical system. I'll just be as careful as I can and try to avoid the situation thats going to put anyone in jeopardy.
 
This thread makes me appreciate one big aspect of our boat. Unless we have the full canvas up and someone goes out onto the aft deck, there's nowhere on deck a person can be that I can't see them from the helm. So if the admiral needs to go out on deck while we're underway, I can always keep an eye on her.
 
boomerang said:
I'm always trying to remain aware of my wifes (and other passengers) location. When she leaves from the flybridge, I will look behind me to make sure she's not swimming in the wake. Often times I'll leave the helm to go below and check on her. Not that shes not a capable person but I consider myself a prudent mariner...and a caring husband.
Our current boat is a double cabin design, which is the all time worst/most dangerous design ever ,IMO, when it comes to ascending & descending to & from the flybridge station.
Regarding the alert gizmos, it's doubtful we'll ever employ one. Realistically, I'm not going to take the time to put the thing on or bring it with me. If conditions are bad, I'm going to hang on to the railings like a cat walking a clothesline and be extra careful and insist my wife does the same. I really don't want an engine cutoff thing incorporated into the system. It's one more thing to potentially go wrong with the electrical system. I'll just be as careful as I can and try to avoid the situation thats going to put anyone in jeopardy.
Click to expand...

Good thing that boat is pretty good to drive from below in anything but ideal conditions, except for a pretty sad helm perch to sit on. Notice the back and leg cutouts..... another necessary mod! :D
 
Jmreim said:
In addition to MOB apps that are built into integrated navigation systems from Simrad, Garmin, Raymarine and others, there are a number of wearable devices on the market specifically designed to alert crew members of a man, woman, child or pet who has fallen overboard. If anyone has experience with these systems, it would be very helpful to learn more about them.

There may also be existing wearable devices that are already widely used for other applications but could be useful for man overboard situations. Fall Detection on an Apple Watch comes to mind but not sure if it can be water activated.

Thx -
Jim
Click to expand...
we Use ACR OLAS great product for us in heavy weather and our puppy all the time
 
You must log in or register to reply here.

Similar threads

C
  • Locked
2003 Pacific Trawler 40 in turnkey condition, lying Bainbridge Island WA -- $224,000
Replies
9
Views
4K
CompuNerd
C
mvweebles
WiFi Network Config for Weebles (Simple - sorta)
2 3
Replies
68
Views
6K
pjtemplin
P
G
Simrad Wifi Setup, First Gen NSS
Replies
2
Views
1K
Gdavid
G
S
Video cameras
2
Replies
31
Views
7K
STB
S
M
For Sale: Raymarine e127
Replies
5
Views
2K
mikesparker
M

Latest posts

Back
Top Bottom