That is an interesting analysis.I was thinking self steering was a good candidate for something which could rip a big hole in the stern area.
Then I read this. Interesting analysis - still conjecture though, as everything will be!
I am of the belief that a boat and it’s crew should arrive at a destination in possibly even finer well oiled, working fettle than when they set out .. from what little onboard vid I have sent, she seems very at one with boat and sea and self .
I have been saying since the last McIntyre Circus, you cannot recreate a bygone 'golden age of sailing', that never existed, using old huls and modern sails and string.So my theory is that the increased tensions on the rigging due to all the above factors, and the age of the boat, led to a fatal crack in the hull, probably at or near the rudder post.
Looking at that immense rebuild, was it completely DIY design or was a professional designer involved? What sort of oversight would there have been from the organisers?We will never know what happened to Tapio's boat, but please indulge me while I explained my diagnosis.
Here are the background facts:
The boat was manufactured sometime in the late 1960s or early 1970s. It was designed by Sparkman and Stephens similar to the Swan 36. Note the counter stern.
Tapio's boat had heavily upgraded rigging, including a shortened mast and much heavier stays. It also had multiple headstays.
The boat sank rapidly after a bang, with no mention of collision shock.
View attachment 146538
Now for my theory.
One of the first engineering principles I learned as a teenager building model aeroplanes, was that reinforcing a structure can throw extra load onto other parts of the structure. It also taught me about stress concentrations.
Creating stronger rigging and a stronger mast allows for much greater tension forces in the rigging. These tension forces create a bending moment on the hull, with upward loads at the bow and stern. Now look at the drawing of the similar Swan 36. Note the potential stress concentration at the end of the counter and the rudder post. The counter is also small and narrow.
The Southern Ocean is cooler than the late summer temperatures that would have been experienced at the start of the race. Lower temperatures would result in rigging contraction and even higher tensions. It is unlikely that Tapio had a chance to retention his rigging at sea. So much higher loads were placed on an old hull, not designed for them.
So my theory is that the increased tensions on the rigging due to all the above factors, and the age of the boat, led to a fatal crack in the hull, probably at or near the rudder post.
So that's my theory, and as Donald Trump would say, "only saying"....
Did they listen?I have been saying since the last McIntyre Circus, you cannot recreate a bygone 'golden age of sailing', that never existed, using old huls and modern sails and string.
I have been saying since the last McIntyre Circus, you cannot recreate a bygone 'golden age of sailing', that never existed, using old huls and modern sails and string.
using old huls and modern sails and string.
Thoughtful supposition - makes sense. But how about the more likely - its a 60 year "old banger" and simply past its sell be date? Everything on a boat ages over the years and all a refit can do is to tackle some of them.We will never know what happened to Tapio's boat, but please indulge me while I explained my diagnosis.
Here are the background facts:
The boat was manufactured sometime in the late 1960s or early 1970s. It was designed by Sparkman and Stephens similar to the Swan 36. Note the counter stern.
Tapio's boat had heavily upgraded rigging, including a shortened mast and much heavier stays. It also had multiple headstays.
The boat sank rapidly after a bang, with no mention of collision shock.
View attachment 146538
Now for my theory.
One of the first engineering principles I learned as a teenager building model aeroplanes, was that reinforcing a structure can throw extra load onto other parts of the structure. It also taught me about stress concentrations.
Creating stronger rigging and a stronger mast allows for much greater tension forces in the rigging. These tension forces create a bending moment on the hull, with upward loads at the bow and stern. Now look at the drawing of the similar Swan 36. Note the potential stress concentration at the end of the counter and the rudder post. The counter is also small and narrow.
The Southern Ocean is cooler than the late summer temperatures that would have been experienced at the start of the race. Lower temperatures would result in rigging contraction and even higher tensions. It is unlikely that Tapio had a chance to retention his rigging at sea. So much higher loads were placed on an old hull, not designed for them.
So my theory is that the increased tensions on the rigging due to all the above factors, and the age of the boat, led to a fatal crack in the hull, probably at or near the rudder post.
So that's my theory, and as Donald Trump would say, "only saying"....
An already strong solid GRP boat was intensively rebuilt. Was it professionally overseen?Thoughtful supposition - makes sense. But how about the more likely - its a 60 year "old banger" and simply past its sell be date? Everything on a boat ages over the years and all a refit can do is to tackle some of them.
Thank you for your detailed post. I don't recall saying Tapio had 'thrown his boat together'. While the skippers are attempting to do is to be admired, I wish I had the resources to do a single handed non-stop circumnavigation in a Boreal 47, I question the whole basis of the event.A long meandering thread. Ignore if you are busy!
Bear in mind the rules have no logical basis - as almost all of the original GGR boats (bilge keelers, trimarans et al) would not qualify.An already strong solid GRP boat was intensively rebuilt. Was it professionally overseen?
It does bring into question the rules of the race, the boats are supposed to be 60 years old, or the design is. With it being rebuilt to different standards, is it still a 60 year old boat?
And agreed by the entrants. Don't like it? Don't do the race.Bear in mind the rules have no logical basis - as almost all of the original GGR boats (bilge keelers, trimarans et al) would not qualify.
Rule 1 (and Rule 2 to infinity) is everything is at the personal whim of the race organiser
Thanks @capnsensible good to see somebody knows their way about. It would be so easy to present the data on a page, we might even call it a dashboardThe website shows you how to download the app. Simples. Updated every 4 hours.
Live Tracker
So easy even engineers can do it.
I have the app and use it daily.Thanks @capnsensible good to see somebody knows their way about. It would be so easy to present the data on a page, we might even call it a dashboard
Meaning everything from clothing, nutrition to bits of string and sails, and the conclusion that it might lead to hulls being overstressed. Let's not even get into the advances in electronic navigation, and the speed and number of large ships plying their trade over the oceans.
I see that while the boat is almost as old as I am it has had a major refit and am questioning what changed in the structure of the vessel.