Crew over board how to find them ?

[a64pilot]

The Mcmurdo s20 has a test function that will set off my Vesper and I believe any other AIS receiver within range, but I guess is just maybe one short pulse as opposed to continuous alarm?
Anyway it could be used as a drill, see attached link to see how the test is done
http://www.mcmurdomarine.com/images/..._Manual_p2.pdf

[Sandero]

Toss the MOB gear and hit the MOB button on all the GPS plotters.... which should at least give you the course to MOB's position when they went in.

[JPA Cate]

Originally Posted by tkeithlu

Secondary question, particularly for us cruising couples. Once you've found your hypothermic mate for life, can you get him/her back on board with no help whatever from him/her? There have been some tragedies of this sort - found alive, but not recovered. I noticed this morning that the water temperature here in north Florida was 57 F. The only chance my wife would have of recovering me would be by my hooking onto a carabiner, and then her lifting me with the electric hoist we use for the dinghy and kayaks.

Yup. Us, too. If conscious, i could hoist Jim with a spinnaker halyard, but his flotation device would have to have crotch straps.

Mostly, we just accept that if you're overboard, you're gone.

Ann

[Dave_S]

Originally Posted by Ann T. Cate

Yup. Us, too. If conscious, i could hoist Jim with a spinnaker halyard, but his flotation device would have to have crotch straps.

Mostly, we just accept that if you're overboard, you're gone.

Ann

Hi Ann

Really, you think the odd are that much against you? That's scary!

[Lou254]

I feel like as humans we like to make it happen despite everything. Why even bother to turn the tiller if we will not try struggling against long odds? Why not wave goodbye and sail on. I feel the ones that say yeah so and so's boat is going under and we are 5 miles down wind in this storm and the water is to cold for any chance of survival would exhaust all efforts to get to them. They know the odds and because of that push even harder to make the improbable happen griping all the way about how it can't I have been in the water. I intend never to go back in. I did not calculate odds. I was an indestructible teen. Odds never really came to my thoughts. Just what can I do to improve my situation. Even now I have to maintain that attitude. We all do to some extent. We get up we participate in life. We prepare for what if and how to prevent it. A lot of times life just happens The way it is but we always keep going against the odds. The best way never to go overboard is to stay on land. That is not going to happen for me. Kind Regards, Lou

[meirriba]

Originally Posted by Sandero

Toss the MOB gear and hit the MOB button on all the GPS plotters.... which should at least give you the course to MOB's position when they went in.

Good for an aware crew situation.
How does it solve the single night watch?

[Stumble]

Originally Posted by Dave_S

Hi Ann

Really, you think the odd are that much against you? That's scary!

I have never seen any statistics on it, but my guess is the recovery rate for someone's who falls overboard at sea is less than 1%. Add an AIS beacon and a properly properly set up ship and I would give you 50/50 odds.

The reality I see that if you fall over underway in seas, it's going to take a lot of time to get the boat back to you. First the second person needs to hear the alarm (if you have one of the proximity alerts) then they need to make it up on deck asses the situation and get to work. Turning the boat around, figuring out the reciprocal course, all while searching for someone in the water (really looking for a strobe light) is amazingly unlikely. Possible, but very unlikely. It could have taken minutes possibly hours before someone even recognizes that you are gone.

Electronics can help... as soon as you fall overboard the chartplotters starts screaming a MOB (proximity alert sensors), marks the GPS position where the person fell overboard, then the AIS MOB kicks in and plots the GPS position of where the MOB is sitting now.

So why only 50/50? Because if anything goes wrong you have no backup. There is absolutly no margin for safety here, it either all works as intended the firs time time or you die.

That's a pretty heavy burden to place on a piece of safety equipment most of us have never actually testes, let alone used in anger.

[meirriba]

1. AIS MOB device depends on line of sight with the boat. I have heard from people who sell these and tried them at sea that the range is highly variable and if the sea is agitated (as it usually will be when MOB happens) the range gets down to few hundreds meters.
2. PLB should be nice, but if the MOB happens far from shore, there is usually no way to contact the boat that lost its crew where the MOB is, as the boat will normally be out of shore stations VHF range.
This is a pity as this would be the nearest boat to the person in the water. Maybe this issue can be solved by having satellite phone on board (or SSB) and the phone registered in the PLB database.
3. If you fall overboard while tethered and there is nobody that takes notice (e.g. single watch at night) you will probably drown, unless the tether is very short and keeps you above water level.
4. VHF radio with all crew would be good for communication but I do not see how you alert someone on board to the situation. Maybe it should be combined with the Bluetooth contraption that makes an alarm when the bearer gets too far from the boat.

It seems to me that the best is to stay on board

[JPA Cate]

Originally Posted by Dave_S

Hi Ann

Really, you think the odd are that much against you? That's scary!

Hi, Steve,

Yes, if at night on passage, during one's partner's off watch. I think daytime overboard situations, if you have the skills, you have a fair chance if you see them go overboard. If you're in the head, or fixing lunch or checking something down below, quite possibly not, especially if it's raining or foggy. People are hard to see in the water.

I disagree that it is scary. It is a fact of sailing, no emotional charge whatsoever. Stay on the boat, take staying on the boat with utmost seriousness.

And, if one has the money, but whatever makes you feel good, but still, stay on the boat.

Ann

[Lou254]

This might be a new thread or I should just start looking though old threads. What type of short teather do you all like? I am in KY. Not exactly a sailing destination. I have to look online at these threads or companies with an online presence. When I get the chance to get close to the ocean I sure do not want to waste time looking at stuff trying to figure out if it will work. The only sailing I get is inland lakes and some on the great lakes. One quick trip to the Bahamas. I look to the future recommend some harnesses and teathers. Kind regards, Lou

[RPZ]

Seems foolhardy to me for solo watches not to be harnessed and tethered when at sea on open cockpit boats, and when out of enclosed cockpits. It is not a major undertaking to have secure lifelines running the length of a boat. Arguably, depending on sea conditions I would include even when there is more than one person on deck, and there are solid siderails all around in clear daylight.

[Stumble]

Originally Posted by meirriba

1. AIS MOB device depends on line of sight with the boat. I have heard from people who sell these and tried them at sea that the range is highly variable and if the sea is agitated (as it usually will be when MOB happens) the range gets down to few hundreds meters.
2. PLB should be nice, but if the MOB happens far from shore, there is usually no way to contact the boat that lost its crew where the MOB is, as the boat will normally be out of shore stations VHF range.
This is a pity as this would be the nearest boat to the person in the water. Maybe this issue can be solved by having satellite phone on board (or SSB) and the phone registered in the PLB database.
3. If you fall overboard while tethered and there is nobody that takes notice (e.g. single watch at night) you will probably drown, unless the tether is very short and keeps you above water level.
4. VHF radio with all crew would be good for communication but I do not see how you alert someone on board to the situation. Maybe it should be combined with the Bluetooth contraption that makes an alarm when the bearer gets too far from the boat.

It seems to me that the best is to stay on board

AIS transmitters operate on the same channels as VHF, so I found you are out of range of one, the other isn't going to work either.

There waster a couple of good articles about these on gCaptain and Panbo, and the take away for me is pretty much the same. AIS or DSC beacons are an attempt to get picked up by the boat you fell off of. PLB's are an attempt to get the normal SAR teams to come find you. AIS/DSC if it works is going to be a far faster response, likely minutes instead of hours, so where possible they are far preferred.

Position broadcast times on the AIS transmitters take about 1 minute from a cold start, then broadcast every 10 seconds or so and it takes 1 minute for the beacon to recognize you are in the water. So if the signal is only picked up every 6th broadcast by the boat, and the boat was traveling at 10kn the boat will pick up the first AIS broadcast when it is .5nm away from you. Easily within range of even a bad transmission over VHF.

Let's assume it takes five minutes for the crew to get the boat turned around, that's still only 1.33nm away from the person I need the water.

Where typically an eight minute leg time between hitting the water and being noticed is pretty much a death sentence at least with an AIS transponder you have a chance. It might be slim, but it is reasonable to think you will be picked up.

A number of AIS transmitters were tested while in the water, and they all came back with a reception range of about 3.5nm. Which works out to 21minutes that the mob isn't within range. If at any time during this the AIS system picks up the broadcast it logs that's location so the ship can at least start the search from there (and hopefully be much closer to the MOB than they otherwise would be.

[a64pilot]

I don't understand the hard to turn the boat around, just let go the lines and let the sails go, crank engine and turn around, drive to the icon on the chart plotter. Deal with the sails once you recover the MOB.
I accept the likelyhood if I'm unconscious I'm gone, but that is pretty unlikely if I'm recovered in 10 min or so? If I'm so wasted I can't come aboard likely I will be able to climb into the dinghy or life raft.

Now in honest to God storm conditions if may be that nothing can be done and that is just the way that it is. In less than that weather maybe you can just get close enough to give them the raft, at least they would have a chance then.
Our tethers are our life vests too, self inflating, although I will likely upgrade them when we leave for the Pacific, by then who knows what will be available

[RPZ]

a64pilot,

If you see them go over the side, I would agree. But even on a moderate sea they are going to tricky to spot. Add limited visibility from the cockpit over the bow, the possibility of a low sun, and you may not see them. And there is also a risk you might run right over them.

[Lou254]

A64 pilot, what kind of life vest ? Who makes it.