Real Probability of Death Passaging the N. Atlantic

[LakeSuperior]

FWIW, I am in the camp of going for the adventure like many CF cruisers. In fact, I have crossed the Atlantic twice on a Mason 44 as a co-owner and co-captain. For many of us it is all about getting out there and meeting the challenge. In some sense we want that glimpse into the abyss.

In a recent thread and in older threads new sailors have been very much urged to just go for it, ignore the naysayers, damn the torpedoes, full speed ahead. Any posters voicing even a hint of caution or reservation have been roundly castigated. Consequently, these threads seem to always come around to grapple with questions about the real risk of ocean passaging.

As has been said many times no one looks out for you like you. So it would be good to have an estimate of what the danger really is. Risk that is 10 or 100 times greater than being in an automobile might give pause. People have crossed the Atlantic in all manner and size of craft and most make it without incident. However, some do not. Consider the fates of sailors in Agecanonix, Escape, and Cheeki Rafiki for example.

Any hard data on sailing death rates is hard to come by or nonexistent. So, when real data can’t be had the next best approach is to make some up. We want to estimate a death rate per 24 hours of passage making in the North Atlantic. An hour searching on the internet showed me 10 deaths from 4 incidents spanning 40 years occurring during Atlantic crossings and north south passages in the US. I saw of 3 deaths in the last two seasons. I personally am aware of addition incidents that didn’t show up in the duckduckgo searches so conservatively let’s settle on an average of 1 death in all the passage making in the North Atlantic per year.

Every year for the last 30 some years there have been approximately 200 ARC yacht crossings. So counting getting there the other way gives us 400 crossing per year related to the ARC. Counting north south passages in the US and additional non-ARC crossing a 1000 passages per year might be a starting place. If we assume each passage is roughly 20 days then there are 20,000 Atlantic passage days per year. Consequently, using these estimates there is a 0.005 percent chance of a single death on a yacht per 24 hours of passaging in the North Atlantic.

Now consider that from the NTSB there are 1.34 fatalities per 100 million vehicle miles. If each vehicle is driven at an average of 40 miles per hour then it is roughly 1.34 deaths per 104,000 days of driving or 0.0013 percent chance of a death in a car per 24 hours of driving.

Consequently, if you believe this analysis, then the odds of a death passaging in the North Atlantic in a sailboat is 3.8 times higher than a death in a car accident.

While these numbers are simply estimates it is likely that passaging in the North Atlantic is somewhat more dangerous than driving around in a car contrary to the many assertions by members of CF. However, it appears the increase in risk is somewhat modest and not 10 times or 100 times riskier.

[chubby]

Originally Posted by LakeSuperior

FWIW, I am in the camp of going for the adventure like many CF cruisers. In fact, I have crossed the Atlantic twice on a Mason 44 as a co-owner and co-captain. For many of us it is all about getting out there and meeting the challenge. In some sense we want that glimpse into the abyss.

In a recent thread and in older threads new sailors have been very much urged to just go for it, ignore the naysayers, damn the torpedoes, full speed ahead. Any posters voicing even a hint of caution or reservation have been roundly castigated. Consequently, these threads seem to always come around to grapple with questions about the real risk of ocean passaging.

As has been said many times no one looks out for you like you. So it would be good to have an estimate of what the danger really is. Risk that is 10 or 100 times greater than being in an automobile might give pause. People have crossed the Atlantic in all manner and size of craft and most make it without incident. However, some do not. Consider the fates of sailors in Agecanonix, Escape, and Cheeki Rafiki for example.

Any hard data on sailing death rates is hard to come by or nonexistent. So, when real data can’t be had the next best approach is to make some up. We want to estimate a death rate per 24 hours of passage making in the North Atlantic. An hour searching on the internet showed me 10 deaths from 4 incidents spanning 40 years occurring during Atlantic crossings and north south passages in the US. I saw of 3 deaths in the last two seasons. I personally am aware of addition incidents that didn’t show up in the duckduckgo searches so conservatively let’s settle on an average of 1 death in all the passage making in the North Atlantic per year.

Every year for the last 30 some years there have been approximately 200 ARC yacht crossings. So counting getting there the other way gives us 400 crossing per year related to the ARC. Counting north south passages in the US and additional non-ARC crossing a 1000 passages per year might be a starting place. If we assume each passage is roughly 20 days then there are 20,000 Atlantic passage days per year. Consequently, using these estimates there is a 0.005 percent chance of a single death on a yacht per 24 hours of passaging in the North Atlantic.

Now consider that from the NTSB there are 1.34 fatalities per 100 million vehicle miles. If each vehicle is driven at an average of 40 miles per hour then it is roughly 1.34 deaths per 104,000 days of driving or 0.0013 percent chance of a death in a car per 24 hours of driving.

Consequently, if you believe this analysis, then the odds of a death passaging in the North Atlantic in a sailboat is 3.8 times higher than a death in a car accident.

While these numbers are simply estimates it is likely that passaging in the North Atlantic is somewhat more dangerous than driving around in a car contrary to the many assertions by members of CF. However, it appears the increase in risk is somewhat modest and not 10 times or 100 times riskier.

i for one do appreciate the fear p0rn..

[Mike OReilly]

I appreciate the attempt LS, but the error bars around your values are way to big to make this meaningful. Meanwhile, we do have solid figures for incident rates for coastal US waters.

For your analysis to be true, ocean travel has to be magnitudes more dangerous. This doesn't pass the sniff test for me. In fact, it's often pointed out that coastal sailing is more dangerous than big open water. The coast is where the dangers are.

[boatman61]

I can think of one year where there were at least 10 deaths on the annual Caribe-Azores run.. A 70ftr disappeared with 7 crew on board and wreckage from another boat with three crew was found, no crew..
There was a third boat lost but cannot recall how many crew were aboard.
Between 1951 and 2006 a total of 309,144 people were killed and 17.6 million were injured in accidents on British roads.
With an average of 6000 death a year I think sailing is safer..

[leecea]

Since I have nothing else to do, I tried imagining the numbers slightly differently (still using your data). Hopefully I did this right...

If there are 1000 passages per year and we assume 4 people per boat, 4000 people sail across per year and 1 dies. So the risk of death is 1/4000.

If 1.34 people die in cars for every 100 million miles, at 40 mph that means 1.34 deaths per 2.5 million hours or 1 death every 1,865,671 hours. Divide by 4000 gives 466 hrs. If you drive 2 hours per day that's 233 days. So 233 days driving 2 hours per day gives you the same odds as sailing across the Atlantic.

Not sure what one would do with this data but it's interesting

[rbk]

Other factors in automobile crashes not taken into account are non-fatal accidents which can be extremely life altering. Fatalities make up only a portion of auto accidents. It’s comparing apples to oranges imo and I’d take my chances on the water any day.

[MicHughV]

One can manipulate facts and figures willy nilly...

To boot.....

If a ship takes 6 days to cross an ocean, six ships can cross an ocean in one day...
1s x 6d = 1c or 6sd = 1c
6s x 1d = 1c or 6sd = 1c

[LakeSuperior]

Originally Posted by Mike OReilly

I appreciate the attempt LS, but the error bars around your values are way to big to make this meaningful. Meanwhile, we do have solid figures for incident rates for coastal US waters.

For your analysis to be true, ocean travel has to be magnitudes more dangerous. This doesn't pass the sniff test for me. In fact, it's often pointed out that coastal sailing is more dangerous than big open water. The coast is where the dangers are.

Mike, I was attempting to get a order of magnitude estimate on the actual risk using reasonable estimates of the underlying numbers. Many have strong opinions on their own perceived risk or gut-level risk estimates. In reality I think I reduced the error bar when compared to these gut-level estimates.

[LakeSuperior]

Originally Posted by boatman61

I can think of one year where there were at least 10 deaths on the annual Caribe-Azores run.. A 70ftr disappeared with 7 crew on board and wreckage from another boat with three crew was found, no crew..
There was a third boat lost but cannot recall how many crew were aboard.
Between 1951 and 2006 a total of 309,144 people were killed and 17.6 million were injured in accidents on British roads.
With an average of 6000 death a year I think sailing is safer..

Try and normalize the denominators and the difference is much closer than you think. Your just looking at the numerators.

[StuM]

Reducing things to hours or 24 hour periods is meaningless.
You don't just sail across the Atlantic for a few hours or for a day.


The only valid number for crossings would be deaths per year as a percentage of people crossing the Atlantic per year. Leecea takes the correct approach so lets take his 1 in 4000 figure for the sake of argument.


Now we have to decide what to compare that too. Again number of people dying against number of people driving would seem appropriate.


Let's take Boaties 6000 deaths per year in the UK. The relevant question there is the number of vehicles/drivers . There are about 50 million registered vehicles and about the same number of registered drivers.
So that's about 1 in 8,333 drivers. If you consider that many of those killed are passengers who are not licenced drivers, cyclists, pedestrians etc, that ratio will be overstated


So the chance of dying on an Atlantic crossing is MORE than double the chance of dying on the roads in the same year, possibly more like triple.

[boatman61]

Originally Posted by StuM

Reducing things to hours or 24 hour periods is meaningless.
You don't just sail across the Atlantic for a few hours or for a day.


The only valid number for crossings would be deaths per year as a percentage of people crossing the Atlantic per year. Leecea takes the correct approach so lets take his 1 in 4000 figure for the sake of argument.


Now we have to decide what to compare that too. Again number of people dying against number of people driving would seem appropriate.


Let's take Boaties 6000 deaths per year in the UK. The relevant question there is the number of vehicles/drivers . There are about 50 million registered vehicles and about the same number of registered drivers.
So that's about 1 in 8,333 drivers. If you consider that many of those killed are passengers who are not licenced drivers, cyclists, pedestrians etc, that ratio will be overstated


So the chance of dying on an Atlantic crossing is MORE than double the chance of dying on the roads in the same year, possibly more like triple.

Keep it up mate..
Us delivery folk love your figures.. scares owners $hit less..

[mjscottinnc]

Your globally generalized risk assessment leaves out 2 very salient factors while comparing this set of apples and oranges. The risk associated with the vessel and the risk associated with the captain & crew. Under an infinite set of risk modifiers, the odds of death could be 100,000 times different (at one death per year, well you get what I mean). Then there is the presence or absence of your personal rabbit foot, phase of the moon, gut feeling... analysis paralysis. Ah, I’ll just keep sailing until I don’t, I’ve got better things to do with my brain.

[ChrisJHC]

Another factor is that once you get offshore, the majority of incidents are “internal” - i.e. involving you and your boat only.

While driving, a not-insignificant number of incidents are caused by other people/vehicles.

[wyb2]

Originally Posted by MicHughV

One can manipulate facts and figures willy nilly...

To boot.....

If a ship takes 6 days to cross an ocean, six ships can cross an ocean in one day...
1s x 6d = 1c or 6sd = 1c
6s x 1d = 1c or 6sd = 1c

I’m sure you already know this, but for anyone who is confused:

This is a misinterpretation of numbers, not an example of making numbers say something that isn’t true.

6 ships got 1/6th of the way there, which is the equivalent of 1 ship getting 6/6ths of the way there.

What defines “a crossing”? Logic would suggest 6 days, but the formulas given have set it to 6 ship-days. Not the same thing.

[Mike OReilly]

Absent even semi-accurate data, this is a meaningless exercise. This is why I point to the moderately credible data already available for events that happen within US jurisdiction. This publicly available data shows just how exceedingly rare it is for a cruising-level boat to come to a bad end.

BTW, has anyone queried organizations like SSCA. Surely it is in their member's interest to keep this kind of data.