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Old 10-07-2019, 14:12   #121
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Re: How Do Couples Cruisers Fall Off Boats?

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Originally Posted by FlyingScot View Post
In theory this sounds great. What happens when it auto tacts accidentally and throws somebody off the boat? Or it auto tacts while sailing downwind and it breaks things. Any accidental signal loss would be very problematic.


Whatís to stop your autopilot from doing that now?
Answer I guess is good design and quality equipment. Same for anything.
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Old 10-07-2019, 14:45   #122
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Re: How Do Couples Cruisers Fall Off Boats?

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In theory this sounds great. What happens when it auto tacts accidentally and throws somebody off the boat?
I simply offered a broad-brushstrokes concept of a system that might work. It wasnít really intended to offer a bullet-proof solution. If I had a bullet proof solution I wouldnít be floating it here, I would be talking to production factories in China . But having said that, my autopilot in 12 years of ownership has never accidentally auto-tacked even once. Given that it requires two buttons to activate auto-tack, itís probably not possible to happen accidentally. I donít know that but it is I think a reasonable assumption.

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Or it auto tacts while sailing downwind and it breaks things. Any accidental signal loss would be very problematic.
In my experience, tacking a boat is not likely to cause damage, no matter how abruptly it happens. If weíre talking about ďauto-gybeĒ of course thatís a different story. But programming the desired movement is surely not difficult. It canít be difficult to get a sensor to determine that if the boat is on a starboard tack, it will auto-tack to starboard and not to port. Also, on my boat, auto-tack happens in a measured albeit relentless way, the likelihood of crew being flipped overboard is pretty small.

So with that as a background, sure, the designers would need to find a solution to the possibility of accidental disconnection which could happen for example due to a battery going flat. But there are many systems that depend on electronics for safe operation, some that could have dire consequences in the event of failure but we use them happily and vary rarely experience accidental failure.

Like I said, broad brushstrokes, not a bulletproof solution.
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Old 10-07-2019, 15:03   #123
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Re: How Do Couples Cruisers Fall Off Boats?

Of course. I’m just thinking out loud too.
Your current autopilot doesn’t listen for a constant radio signal.
It seems it would be hard to have one that acts fast enough to save your life but not have false triggers.
I like the idea. It’s the details that would make it very hard to implement.
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Old 10-07-2019, 15:30   #124
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Re: How Do Couples Cruisers Fall Off Boats?

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I simply offered a broad-brushstrokes concept of a system that might work. It wasnít really intended to offer a bullet-proof solution. If I had a bullet proof solution I wouldnít be floating it here, I would be talking to production factories in China . But having said that, my autopilot in 12 years of ownership has never accidentally auto-tacked even once. Given that it requires two buttons to activate auto-tack, itís probably not possible to happen accidentally. I donít know that but it is I think a reasonable assumption.







In my experience, tacking a boat is not likely to cause damage, no matter how abruptly it happens. If weíre talking about ďauto-gybeĒ of course thatís a different story. But programming the desired movement is surely not difficult. It canít be difficult to get a sensor to determine that if the boat is on a starboard tack, it will auto-tack to starboard and not to port. Also, on my boat, auto-tack happens in a measured albeit relentless way, the likelihood of crew being flipped overboard is pretty small.



So with that as a background, sure, the designers would need to find a solution to the possibility of accidental disconnection which could happen for example due to a battery going flat. But there are many systems that depend on electronics for safe operation, some that could have dire consequences in the event of failure but we use them happily and vary rarely experience accidental failure.



Like I said, broad brushstrokes, not a bulletproof solution.

Rather than alerting when a signal stops, how about alerting when a signal starts? That is a personal man overboard beacon (PMOB) and they come in two flavours: AIS and EPIRB. The latter is good for recovering your body, but the former will plot your position on your plotter and sound your AIS MOB alarm.

With an AIS PMOB get one that also sends a GPS signal - that way the position of the MOB marker is updated with the current position of the MOB.

Since there are NMEA signals between the AIS and chart plotter I assume a decent programmer could use that signal to send additional instructions to the plotter to tack the boat or whatever.

The one drawback to AIS beacons is that they take about 30-60 seconds to send the first signal, so depending on the speed of the boat you may get out of range (VHF range) relatively quickly. And is the audio alarm loud enough to wake the off watch?

Of course, finding the MOB is only half the problem - the other half is getting them back on board.

Regarding the line trailing behind, great idea, especially if tugging on it also deploys a sea anchor or a Jordan Series Drogue. The boat stops or slows radically and then you can pull yourself back to the boat. Then board. Neither is easy, but better than getting left behind (amazing story about John getting picked up by a cruise ship and getting taken back to his boat).
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Old 10-07-2019, 16:32   #125
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Re: How Do Couples Cruisers Fall Off Boats?

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Whatís to stop your autopilot from doing that now?
Answer I guess is good design and quality equipment. Same for anything.

I think his point was that if this new wireless device (which is superposed to trigger at a set distance) lost signal, that would trigger a tack. There is no such trigger on current autopilots.


One problem with tripping the autopilot is that this must be adjusted to the sails set (upwind, reaching, and down wind are different). For example, turn 90 degrees while on a broad reach in a blow and the boat might not even slow much. Or perhaps you forgot to reset it after the last tack and it turns the wrong way. And of course, if you are motoring, it just keeps going. All of these behaviors are fixable, but they require telling the devise about changes you have made.


I the video I shared it tool me about 6 seconds to reach the line in no real hurry, wearing a PFD on a boat with an 18' beam (which is more than most), going about 7 knots, but not falling outboard. I expect in rough weather and if it were a surprise, that 10 seconds would be a very good effort. I had 150' of line out, and it was not excessive for a fair weather test. You can see I am well down the line. This boat is capable of ~ 17 knots, and we tested up to 12 knots, once with the chute up. Rather interesting, one chute pulling hard against another.



The advantage is that there is nothing to adjust. But scaling it up to large, heavy boats is impractical. That said, my target was small, solo boats, which are hard to protect with jacklines.


It was just a thought exercise, really. I was hoping for fun comments. It did work ,every time. It is also really weird to watch the boat going away from you. It seems really fast when you are in the water!
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Old 10-07-2019, 16:37   #126
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Re: How Do Couples Cruisers Fall Off Boats?

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Of course. Iím just thinking out loud too.
Your current autopilot doesnít listen for a constant radio signal.
It seems it would be hard to have one that acts fast enough to save your life but not have false triggers.
I like the idea. Itís the details that would make it very hard to implement.

Note: these devises do exist to turn the engine off. There are a number of them. Trigger distance is a challenge. Generally the boat will stop ~ 200 feet away (momentum) and will then drift as fast as you can swim, if there is much wind. Intriguing.
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Old 10-07-2019, 16:43   #127
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Re: How Do Couples Cruisers Fall Off Boats?

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thinwater, on my long night watches, I used to get out of the cockpit, not clip on, and take a tour round the deck, sometimes to look at dolphins' phosphorescence, sometimes to get more "awake". Sometimes, I would sit on the bow pulpit, holding on, but enjoying the nighttime view of the boat sailing along on her course. Never fell off, but neither was the behavior "safety conscious." I enjoyed those times.

I think some fall off due to alcohol consumption (Natalie Woods' death, though could easily have been pushed, for instance).

Of course one doesn't know (like from having observed) what others do, but I think when the motion is lurchy at sea, and everything's wet from rain or salt spray is probably the most vulnerable, short of knockdowns and roll overs.

How I used to do it, was if I was scared to go forward to do something, because of the motion, that's when I made myself clip on, and go do it, before *things* got worse. Now that we are older, we don't consecutively singlehand the boat: we have both people in the cockpit for reefing. No one's going overboard unnoticed. Whether circumstances allow recovery or not, is in the hands of the fates.

The worst fall I had on a boat was while I had my harness on, job completed, and I started below for something. I tripped on my tether as I came over the bridge deck, and fell to the cabin sole, striking my head and back as I went down. A day or so later, we arrived in a harbor, and I went to the doctor. No serious damage, but the bruises were ugly and sore for quite a while. It was scary for Jim, too, because there was an awful thump when I landed. Not a fun way to wake up.

The only time i ever saw Jim fall on a boat was on some friends' boat, during a spinnaker take down, when they had not laid the pole against the forestay, and when he loosed the shackle, the pole moved towards where he was standing, and he received a blow to his head, that broke his nose. Fortunately, he fell on deck, and was immediately seen to by the owner's wife.

Ann
As usual Ann, you hit on the essence of Sea life.
What you are comfortable with and "Fate"

Tethers and lifejackets were used for extreme conditions

You always went to the bow via the "high side" so you could fall into the boat.

An off watch person was very near to cockpit if needed.

As you get older, you become more conservative, but as that Sad Sydney child drowning illustrates......
, sometimes Fate plays a major role, despite our best planning and precautions
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Old 10-07-2019, 19:21   #128
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Re: How Do Couples Cruisers Fall Off Boats?

Every automatic identification system (AIS) man overboard (MOB) transmitter has its own unique assigned maritime mobile service identity (MMSI). The nine-digit MMSIs for AIS MOB's (also called AIS SARTs - Search And Rescue Transmitters) all start with the digits 972. When activated, they continually transmit the lat/lon of the victim.

Triggering an on-board alarm when there's an AIS MOB activated is a problem that has already been solved, rather cheaply. If you have a modern VHF radio with an integral AIS receiver, it probably already supports AIS MOB alarms.

Since AIS MOB's provide the victim's lat/lon coordinates to high resolution, interfacing with the autopilot could command the vesel to simply steer the boat back to the victim, and then circle.

It would be helpful to have the ability to register only your own vessel's MOB MMSIs for automatic response. Otherwise, I have scary images in mind of multiple vessels self-steering to the same point. And yes, I know bad things can happen when a robot takes control to affect a sudden radical course change. But for we single-handers, solo watchstanders, and vessels with the only person who knows how to sail falling overboard, it's our only hope. Even for experienced crew, it would take a lot of the panic and scurrying around out of an MOB incident to have the boat steer itself back to the victim. The robot may not handle the boat as well as you, but it might be you in the water.

All the elements of the technology are already available. It's just a software and interface challenge. All we need is some product developer to take the initiative. Raymarine: are you listening?

Here's more info on AIS MOB alarm integrations into VHF radios: https://www.panbo.com/testing-ais-mob-beacons-acr-dsc/
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Old 11-07-2019, 08:13   #129
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How Do Couples Cruisers Fall Off Boats?

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I think his point was that if this new wireless device (which is superposed to trigger at a set distance) lost signal, that would trigger a tack. There is no such trigger on current autopilots


Well, there actually is such a trigger, the flux gate compass or whatever you autopilot uses for heading, can break of course.
A Pro installed my Brothers autopilot on his Sportfisherman years ago and it would hard over after a few seconds of being engaged, I finally figured out the compass was installed upside down, the fix was easy, swapping the port and starboard wires. But autopilots can of course malfunction.

But neither here nor there, there are two ways to make what he is propositioning work, one is loss of signal which I wouldnít do, all it would take for that to go bad is a battery going dead, however you could make it so that it doesnít trip until a signal is received, same type of trigger that inflates your vest for example, good ones seem to never false, but also I would assume operate almost immediately if you fall in.

I only bring it up as I think itís an easily solvable dilemma, not that I think a rudder hard over is a viable solution, but it wouldnít hurt, Reminds me of my old jet ski.

Anything is possible with enough money, you could even have something built that would start the engine, engage the transmission and navigate to the AIS SART.
All it takes is money.
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Old 11-07-2019, 08:22   #130
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Re: How Do Couples Cruisers Fall Off Boats?

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Maybe, since it's thinwater's thread and he wants to talk about recovery, have any more of us had to recover someone from the water? So far, we have one Lifesling recovery, and CF member, Kenomac, has also had one successful Lifesling recovery.

Anyone else?

What method?

Anything you'd do differently?

Ann
I was taught this method to haul in a MOB by Mr. Van Breems. Practiced it a couple of times during the US Sailing Basic Cruising class I took at his school.

Here is how we get the person back on board the boat:

Attach a block to a strong halyardómain or spinnaker.

Run a hoist line, preferably with a snap shackle on its end, through the block on the halyard and clip the snap shackle to the D rings on the LifeSling harness.

Pass the hoist line through a block on the deck that is positioned to give it a fair lead to a primary winch. Sometimes a genoa lead block is fine, but often such a block is too far forward. A block on the toerail a few feet aft of the lifeline gate is ideal, as the MOB can be brought through the gate.
Raise the halyard till the block is about 8ft to 10ft above the deck. Open the lifeline gate.

Using the primary winch, which is hopefully self-tailing, hoist the MOB back onboard. The 2:1 purchase, combined with the power of the primary winch, should be sufficient for a weaker crew member to hoist a fully clothed and dripping wet adult male on board.

https://www.sailmagazine.com/cruisin...ice-techniques
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Old 11-07-2019, 08:46   #131
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Re: How Do Couples Cruisers Fall Off Boats?

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one is loss of signal which I wouldn’t do, all it would take for that to go bad is a battery going dead, however you could make it so that it doesn’t trip until a signal is received
Actually the loss of signal method is the most reliable. Yeah, if it fails you get a false alarm but this can be made very reliable so that almost never happens. This is the foolproof idea of a dead-man switch or watch-dog timer in embedded electronics. Do it the other way, and a failure means no alarm for the mob. If you are protecting life, you 'll want it the first way for sure.

There are already systems available that do this, using a small fob attached to each person. Crew Watcher uses a smart phone and BlueTooth, with a 3 year battery. Others use WiFi and are rechargeable. Simple stuff. Controlling the autopilot? Complicated.

You can also attach some of the fobs to a dinghy to alert you when someone borrows it at 3:00am.
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Old 11-07-2019, 12:59   #132
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Re: How Do Couples Cruisers Fall Off Boats?

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Actually the loss of signal method is the most reliable. Yeah, if it fails you get a false alarm but this can be made very reliable so that almost never happens. This is the foolproof idea of a dead-man switch or watch-dog timer in embedded electronics. Do it the other way, and a failure means no alarm for the mob. If you are protecting life, you 'll want it the first way for sure.

There are already systems available that do this, using a small fob attached to each person. Crew Watcher uses a smart phone and BlueTooth, with a 3 year battery. Others use WiFi and are rechargeable. Simple stuff. Controlling the autopilot? Complicated.

You can also attach some of the fobs to a dinghy to alert you when someone borrows it at 3:00am.

I hope we aren't re-inventing the wheel here.

  • AIS MOBs are available from several sources. They can be configured to trigger on inflation of a PFD along with manual triggering.
  • Several modern VHF receivers support AIS and alarms on reception of AIS MOBs.
  • And the activation of an AIS MOB will alert not only your crew, but also any nearby vessels equipped with modern VHF/AIS receivers -- as well as the Coast Guard in coastal areas.
The Coast Guard radio antennas are on towers with extensive line-of-sight coverage (generally 25 miles offshore, what's called "sea area 1" in GMDSS parlance). I've heard the CG call several vessels already when they had an accidentally activated AIS MOB on board.


So if you still have an old-technology VHF radio, you'll have to upgrade, but the cost isn't outrageous. And you'll have to buy AIS MOBs. I have one on every PFD on board my boat.
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Old 11-07-2019, 13:33   #133
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Re: How Do Couples Cruisers Fall Off Boats?

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I hope we aren't re-inventing the wheel here.
We also have the AIS MOBS (Ocean Signal) on vests.
Though, I think the out-of-proximity proximity alarm would be great at anchor if you could get kids to wear them somehow. Jumping off of a perfectly floating boat seems to always be the goal of kids I know. That's probably a different discussion than couples falling off boats...
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Old 11-07-2019, 15:26   #134
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Re: How Do Couples Cruisers Fall Off Boats?

There is not much point in theorising about how people go over the side unless one can come up with remedies.

No one properly harnessed and clipped to a centrally rigged running line goes overboard. That is the simplest and best way of crawling along a deck to remedy a fault in the filthiest of weather--but of course one has to rig the line in advance, and there is much to be said for having a central set of attachments for the rigging of such a line at the first sign of a squall.

In the event someone does manage to go into the drink--a "Second Chance" knotted at intervals rope trailed astern is usual. It needs to be at least 50 metres in length, and longer is better.

If one is injured it may not be to much avail, but if one has merely slipped, a few quick strokes should enable one to grasp it with both hands and hang on for dear life. I rigged mine to a stern cleat next to a swim ladder, but pulled aside by a pair of ties. One is string designed to break when weight is applied to the second-chance, the other is strong and goes to a clamp-and-tongue switch that turns on the fog horn and a cabin siren when the tongue is pulled from the jaws and they make electrical contact. No one sleeps through that noise.

That is the basic system.

Yes it is great if one has the modern stuff aboard--the GPS devices and man overboard alarms that are distance-activated--but for those looking for something to tide them over until funds for such purchases accrue, the Second-chance and a tension alarm are cheaply and quickly devised from a knotted rope, some strings, a clothes peg and some wires.

I might also add that the chances of regaining the deck using a second-chance rope decrease as the speed of the vessel increases, so multihull sailors need to reef well in advance of bad weather, because over five knots it is hard to hold on to the rope let alone drag oneself back to the vessel. The alarm attached thereto is the REAL second chance--provided one can reach the rope. One has only a few seconds in which to do so.
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Old 11-07-2019, 17:06   #135
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Re: How Do Couples Cruisers Fall Off Boats?

Anyone have experience with these or a similar app based product?
https://www.acrartex.com/products/acr-olas-tag
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