What are the factors that lead to a dismasting?
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Accidental Jibe
An Accidental Jibe will put incredible amount of Stress on all your rigging Not sure , but i think this is the No.1 Reason Anyone that has had an accidental jibe can tell you that it os a scarey split second. Tony B
An Accidental Jibe will put incredible amount of Stress on all your rigging Not sure , but i think this is the No.1 Reason Anyone that has had an accidental jibe can tell you that it os a scarey split second. Tony B
Rigging failure
From a cruising point of view, I would think that most dismastings are caused by a failure of one of the rig components, which is why these should be inspected yearly. I would guess most sailors, at one time or another, have suffered an accidental jibe, and unless it happens in heavy air, I would expect a properly designed rig to be able to withstand it. I know that racers on the Great Lakes break masts when thunder storms blow through with higher than expected gusts catching boats with too much sail up.
From a cruising point of view, I would think that most dismastings are caused by a failure of one of the rig components, which is why these should be inspected yearly. I would guess most sailors, at one time or another, have suffered an accidental jibe, and unless it happens in heavy air, I would expect a properly designed rig to be able to withstand it. I know that racers on the Great Lakes break masts when thunder storms blow through with higher than expected gusts catching boats with too much sail up.
I think a violent 360 roll could cause a dismast
Reading the conditions he was in in and the report that said "dismasted, lost steering and is has a hatch that is broken and leaking" and in the Southern Ocean I am thinking he got caught by a rogue wave and rolled the boat. That would also account for the dmamged steering and the broken hatch. My heart goes out to him and his family. I can't even imagine whats going through his mind. It sounds like he got into a a little "bad luck" weather. But this is a circumnavigation and that is to be expected. This being his first true blue water sailing sounds like he bit a little bit more off than he could chew. Good luck to him.
Reading the conditions he was in in and the report that said "dismasted, lost steering and is has a hatch that is broken and leaking" and in the Southern Ocean I am thinking he got caught by a rogue wave and rolled the boat. That would also account for the dmamged steering and the broken hatch. My heart goes out to him and his family. I can't even imagine whats going through his mind. It sounds like he got into a a little "bad luck" weather. But this is a circumnavigation and that is to be expected. This being his first true blue water sailing sounds like he bit a little bit more off than he could chew. Good luck to him.
missing cotter pin
The only time that I've come close to losing the mast was on the day I launched my first boat, a Columbia Sabre. We had stepped the mast (deck stepped) and were late getting away from the dock for a 3 hour transit to our home slip. In the rush, someone left a cotter pin out of a turnbuckle clevis pin, and on a hard tack, the pin fell out, and we lost the forward starboard shroud at the chain plate with a loud TWANG. Thank the Lord for double lowers. We were able to resecure the shroud, and secured the pin with seizing wire. I always check my turnbuckles now, before leaving the slip, and again, before I leave the boat. Larry Wilson
The only time that I've come close to losing the mast was on the day I launched my first boat, a Columbia Sabre. We had stepped the mast (deck stepped) and were late getting away from the dock for a 3 hour transit to our home slip. In the rush, someone left a cotter pin out of a turnbuckle clevis pin, and on a hard tack, the pin fell out, and we lost the forward starboard shroud at the chain plate with a loud TWANG. Thank the Lord for double lowers. We were able to resecure the shroud, and secured the pin with seizing wire. I always check my turnbuckles now, before leaving the slip, and again, before I leave the boat. Larry Wilson
Several years ago.....
during a race in a 7-10 knot breeze the mast on my Kittiwake 23 (a design by Carl Alberg similar to a Cape Dory) broke at the spreader. After a reach on the first leg, we round the mark and hardened up for the leg to windward. Moments later I happened to look up in time to see the mast undulating at the spreader....it fell to windward in a split second with no warning. Having prided myself on maintaining a well kept boat, I remain puzzled to this day as to why it broke. Even the insurance company's marine surveyor could not determine the failure reason; the adjuster tried to make it sound as if I had done something to cause the break in order to get a new mast. But the marine surveyor ruled against him, saying the boat demonstrated the proper care and maintenance by its meticulous owner. As he said, "Sometimes they just break." D. Dixon s/v CD EXPRESS
during a race in a 7-10 knot breeze the mast on my Kittiwake 23 (a design by Carl Alberg similar to a Cape Dory) broke at the spreader. After a reach on the first leg, we round the mark and hardened up for the leg to windward. Moments later I happened to look up in time to see the mast undulating at the spreader....it fell to windward in a split second with no warning. Having prided myself on maintaining a well kept boat, I remain puzzled to this day as to why it broke. Even the insurance company's marine surveyor could not determine the failure reason; the adjuster tried to make it sound as if I had done something to cause the break in order to get a new mast. But the marine surveyor ruled against him, saying the boat demonstrated the proper care and maintenance by its meticulous owner. As he said, "Sometimes they just break." D. Dixon s/v CD EXPRESS
Rigging
Not having your standing rigging properly tensioned is probably a big factor. If there is slack in the shrouds, each time the wind changes side on your sails, there is a great surge of pressure against the rigging, connection points, mas, and deck. Eventually something is going to break. If the rigging is properly tensioned, the impact load is greatly reduced. An accidental gybe is just another way to put the high impact onto your rigging. Care should be taken to prevent an accidental gybe by using a preventer (catchy name, eh?) when sailng on a dead run. Sailing with the wind on your quarter is another way to prevent an acidental gybe. I tie a stopper knot in my mainsheet so that when fully extended, my boom cannot touch my shrouds. If you have a gybe and the boom swings against the shroud, it's quite likely to break something.
Not having your standing rigging properly tensioned is probably a big factor. If there is slack in the shrouds, each time the wind changes side on your sails, there is a great surge of pressure against the rigging, connection points, mas, and deck. Eventually something is going to break. If the rigging is properly tensioned, the impact load is greatly reduced. An accidental gybe is just another way to put the high impact onto your rigging. Care should be taken to prevent an accidental gybe by using a preventer (catchy name, eh?) when sailng on a dead run. Sailing with the wind on your quarter is another way to prevent an acidental gybe. I tie a stopper knot in my mainsheet so that when fully extended, my boom cannot touch my shrouds. If you have a gybe and the boom swings against the shroud, it's quite likely to break something.
Chainplates
On my O'Day 25 (single lowers), the chainplates had been leaking, and rotted the bulkhead. The teak veneer covered up the poor condition nicely, and I didn't know enough to inspect under the chainplates. One day the chainplate gave way on a tack, and down came the mast.
On my O'Day 25 (single lowers), the chainplates had been leaking, and rotted the bulkhead. The teak veneer covered up the poor condition nicely, and I didn't know enough to inspect under the chainplates. One day the chainplate gave way on a tack, and down came the mast.
Knock Down with Waves
I believe that mast failures off shore are mostly the result of knock-downs in high seas. The reefed main is submerged and becomes a water tank. the next wave lifts the hull, but the submerged sail does not have lift, and puts high strain on the mast, which then fails. Many non-fiction accounts of rig failure have this kind of scenario in common. More ominously, if the broken mast is not quickly detached from the rigging, it can become a battering ram, which will smash the hull, leading to sinking.
I believe that mast failures off shore are mostly the result of knock-downs in high seas. The reefed main is submerged and becomes a water tank. the next wave lifts the hull, but the submerged sail does not have lift, and puts high strain on the mast, which then fails. Many non-fiction accounts of rig failure have this kind of scenario in common. More ominously, if the broken mast is not quickly detached from the rigging, it can become a battering ram, which will smash the hull, leading to sinking.
rigging failure
I guy was dismasted at my old marina and his chainplate pulled out of rotted wood. Broke off at spreaders. A Cape Dory that I was looking at had lost it's mast twice!!! Both times at the spreaders. This makes sense as the mast is usually well supported at the spreaders by the rigging. Supposedly if you have tight lower shrouds and looser uppers the mast will suffer metal fatique. I read that the uppers should be under greater tension since they are longer. My loos gauge has recommended tension based on the wire's diameter. Using these numbers my uppers are under greater tension because they are heavier wire. I had a cracked turnbuckle that I replaced. It was to an upper shroud and I imagine that if it broke under load the mast would have a lot of stress. Most masts are not very strong except in compression. The wires take all of the lateral loads. My older mast has heavy gauge metal and a wide cross section. Some of the newer masts are much thinner in the walls and in cross section. I guess this is why many have double spreaders. They would seem even more vulnerable to a broken wire. I saw an article on a failed mast. The boat's owner had installed a lot of hardwire which required a lot of holes. Then with disimular metals electrolysis further weakend the mast and it broke along the line of scew holes. They didn't mention it in the article but I bet loose stays were a contributing factor. Aluminum is particularly suspectible to metal fatique.
I guy was dismasted at my old marina and his chainplate pulled out of rotted wood. Broke off at spreaders. A Cape Dory that I was looking at had lost it's mast twice!!! Both times at the spreaders. This makes sense as the mast is usually well supported at the spreaders by the rigging. Supposedly if you have tight lower shrouds and looser uppers the mast will suffer metal fatique. I read that the uppers should be under greater tension since they are longer. My loos gauge has recommended tension based on the wire's diameter. Using these numbers my uppers are under greater tension because they are heavier wire. I had a cracked turnbuckle that I replaced. It was to an upper shroud and I imagine that if it broke under load the mast would have a lot of stress. Most masts are not very strong except in compression. The wires take all of the lateral loads. My older mast has heavy gauge metal and a wide cross section. Some of the newer masts are much thinner in the walls and in cross section. I guess this is why many have double spreaders. They would seem even more vulnerable to a broken wire. I saw an article on a failed mast. The boat's owner had installed a lot of hardwire which required a lot of holes. Then with disimular metals electrolysis further weakend the mast and it broke along the line of scew holes. They didn't mention it in the article but I bet loose stays were a contributing factor. Aluminum is particularly suspectible to metal fatique.
standing rigging
It's not about crash gybes and rollovers. Most dismastings occur as the result of failure in the standing rigging. Several years ago I was crewing on a six-month-old Junneau 40 when the cap shroud jumped out of the upper spreader. The mast broke right at the spreader. This happened again last season to a J-24 that the junior sailors from my yacht club were racing. The plastic seizing cap simply wore through, and the stick came down in the middle of a tack. A five dollar part that should have been replaced years before cost them a stick. When shrouds and spreaders separate, masts break. When shrouds and stays part, masts break. Those who use seizing wire should check the integrity of the connection regularly. Turnbuckles, chainplates, shrouds and stays should be inspected at the beginning of each season. Standing rigging should be replaced every ten years.
It's not about crash gybes and rollovers. Most dismastings occur as the result of failure in the standing rigging. Several years ago I was crewing on a six-month-old Junneau 40 when the cap shroud jumped out of the upper spreader. The mast broke right at the spreader. This happened again last season to a J-24 that the junior sailors from my yacht club were racing. The plastic seizing cap simply wore through, and the stick came down in the middle of a tack. A five dollar part that should have been replaced years before cost them a stick. When shrouds and spreaders separate, masts break. When shrouds and stays part, masts break. Those who use seizing wire should check the integrity of the connection regularly. Turnbuckles, chainplates, shrouds and stays should be inspected at the beginning of each season. Standing rigging should be replaced every ten years.
Snagged shrouds ...
I read an account of a couple who were heading south and were on the ICW in New Jersey. I think they were motoring along the waterway and for a moment of inattention they brushed past a bouy and snagged their shroud, bringing the whole mast down on their 32' boat.
I read an account of a couple who were heading south and were on the ICW in New Jersey. I think they were motoring along the waterway and for a moment of inattention they brushed past a bouy and snagged their shroud, bringing the whole mast down on their 32' boat.
chain plates
Standing rigging at the bottom swage. Water rust the wire expanding the fitting. Or the chain plates go due to leaks and the water rust them at the point where they go threw the deck. These are the most common that I see.
Standing rigging at the bottom swage. Water rust the wire expanding the fitting. Or the chain plates go due to leaks and the water rust them at the point where they go threw the deck. These are the most common that I see.
Good topic!
The causes of dimastings are as varied as the rigging of boats. On a race boat, not getting the runners on during a normal gybe can have the stick out of the boat. Good cruising rigs should stand with any one shroud broken. Excellent cruising rig design allows any two shrouds to fail and the mast remain upright long enough for the crew to react (change tacks etc to relieve stress). For example, on a Catalina 30, the 304 alloy 3/16" lowers are marginal, the mast will probably stand if one breaks. Replacement with 316 alloy lowers in 3/16" puts them over the edge IMO. I like to see 7/32" wire and 304 alloy for those shrouds. Many boats from the 70's were designed with 304 or 302 alloy wire, 316 alloy is 15% weaker and can increase the risk of failure on boats that have minimum safety margins built into the rig. What we are starting to see is wires failing from age. Stainless steel has a finite fatigue limit before it becomes suspect. It can look fine and show no external flaws and fail the next day. A good rule of thumb is to pull the mast and do a detailed inspection every 5 years. Some riggers recommend 1x19 wire be replaced every 5-7 years, particularly 316 alloy. Navtec says rod and wire should get a professional inspection after 40,000 miles. True, there are boats that sail with 30 year old wire and the rigs don't drop, but no one can say that the rigging is sound. Just because the boat is not sailed often does not prevent fatigue stress, a loose rig rolling in the slip with each wake and gust of wind can fatigue the wire just as fast as sailing the boat to Hawaii. Reusing cotter pins is a no-no. Using split rings instead of cotters to secure clevis pins is a no-no. Using mismatched pin and hole sizes is a no-no. A 1/4" wire might have a 3/8", 7/16", or 1/2" pin. Putting a 3/8" pin into a 1/2" chainplate because the turnbuckle toggle will only take a 3/8" pin is asking for trouble. The 3/8" pin in a 1/2" hole is much weaker than the same 3/8" pin in a 3/8" hole. If the chainplates have 3/8" holes 3/8" turnbuckles should be used, if the holes are 1/2", use 1/2" turnbuckles. What is scary is I've seen brand new production boats where the turnbuckles have been downsized but the chainplates still have larger holes. This is on factory supplied rigging! Speaking of turnbuckles, stainless turnbuckles that use stainless rigging screws are automatically suspect. They require yearly inspection (complete removal of the turnbuckle body for cleaning, thread inspection, and lubrication. These are the ones that make the screech of death as the threads gall when you try to adjust them.
Chrome Bronze turnbuckles with stainless rigging screws are fine, the seldom seize or gall. Navtec turnbuckles used to come with SS rigging screws, if you have these, replace the screws with bronze and then replace the rigging screws every 40,000 miles or 10 years. Installing roller furling on a headstay that has no toggle at the masthead can bring the rig down. As mentioned earlier, loose rigs cause more problems than properly tuned rigs. If the rig will not hold it's tune for the sailing season, there is something wrong. The wire is no longer elastic, the chainplates are distorting, the compression post or deck is crushing, the hull is getting soft ... something is wrong. Yes I'm a rigger, I'm not trying to sell things that are not needed. We make more money replacing the whole mast and rigging after it fails than we do just replacing the wire. The insurance companies are starting to take a look at this and rig inspection requirements for insurance surveys will probably get stricter in the next few years. 15-20 year old wire may not be insurable. Once the rig is in good condition and well tuned, roll over and collision are the most common causes of dismastings.
The causes of dimastings are as varied as the rigging of boats. On a race boat, not getting the runners on during a normal gybe can have the stick out of the boat. Good cruising rigs should stand with any one shroud broken. Excellent cruising rig design allows any two shrouds to fail and the mast remain upright long enough for the crew to react (change tacks etc to relieve stress). For example, on a Catalina 30, the 304 alloy 3/16" lowers are marginal, the mast will probably stand if one breaks. Replacement with 316 alloy lowers in 3/16" puts them over the edge IMO. I like to see 7/32" wire and 304 alloy for those shrouds. Many boats from the 70's were designed with 304 or 302 alloy wire, 316 alloy is 15% weaker and can increase the risk of failure on boats that have minimum safety margins built into the rig. What we are starting to see is wires failing from age. Stainless steel has a finite fatigue limit before it becomes suspect. It can look fine and show no external flaws and fail the next day. A good rule of thumb is to pull the mast and do a detailed inspection every 5 years. Some riggers recommend 1x19 wire be replaced every 5-7 years, particularly 316 alloy. Navtec says rod and wire should get a professional inspection after 40,000 miles. True, there are boats that sail with 30 year old wire and the rigs don't drop, but no one can say that the rigging is sound. Just because the boat is not sailed often does not prevent fatigue stress, a loose rig rolling in the slip with each wake and gust of wind can fatigue the wire just as fast as sailing the boat to Hawaii. Reusing cotter pins is a no-no. Using split rings instead of cotters to secure clevis pins is a no-no. Using mismatched pin and hole sizes is a no-no. A 1/4" wire might have a 3/8", 7/16", or 1/2" pin. Putting a 3/8" pin into a 1/2" chainplate because the turnbuckle toggle will only take a 3/8" pin is asking for trouble. The 3/8" pin in a 1/2" hole is much weaker than the same 3/8" pin in a 3/8" hole. If the chainplates have 3/8" holes 3/8" turnbuckles should be used, if the holes are 1/2", use 1/2" turnbuckles. What is scary is I've seen brand new production boats where the turnbuckles have been downsized but the chainplates still have larger holes. This is on factory supplied rigging! Speaking of turnbuckles, stainless turnbuckles that use stainless rigging screws are automatically suspect. They require yearly inspection (complete removal of the turnbuckle body for cleaning, thread inspection, and lubrication. These are the ones that make the screech of death as the threads gall when you try to adjust them.
Chrome Bronze turnbuckles with stainless rigging screws are fine, the seldom seize or gall. Navtec turnbuckles used to come with SS rigging screws, if you have these, replace the screws with bronze and then replace the rigging screws every 40,000 miles or 10 years. Installing roller furling on a headstay that has no toggle at the masthead can bring the rig down. As mentioned earlier, loose rigs cause more problems than properly tuned rigs. If the rig will not hold it's tune for the sailing season, there is something wrong. The wire is no longer elastic, the chainplates are distorting, the compression post or deck is crushing, the hull is getting soft ... something is wrong. Yes I'm a rigger, I'm not trying to sell things that are not needed. We make more money replacing the whole mast and rigging after it fails than we do just replacing the wire. The insurance companies are starting to take a look at this and rig inspection requirements for insurance surveys will probably get stricter in the next few years. 15-20 year old wire may not be insurable. Once the rig is in good condition and well tuned, roll over and collision are the most common causes of dismastings.
Lost a Few
Missing cotter pins twice. The mast held once but had a bend. With deference to Moody, both times were following a re-rig. The third time was a lower eye letting go and the fourth was an upper swage fitting cracked. Two were my boat, one twice. I like free-standing rigs a lot. RD
Missing cotter pins twice. The mast held once but had a bend. With deference to Moody, both times were following a re-rig. The third time was a lower eye letting go and the fourth was an upper swage fitting cracked. Two were my boat, one twice. I like free-standing rigs a lot. RD
John (et.al.) yes you are correct
Typical dismastings are due to simple rigging failures like broken tangs or cotter pins falling out. Sorry, I read the question wrong, I was trying to figure out (guess) what might have happened to that boat solo sailing that got dismasted If anyone read "Red Sky in Mourning" its a true story of a woman that lost her loved one overboard due to a "HUGE" wave that rolled their boat and just snapped the tether he was on. She came to a day later in the salon very groggy with about a foot of water in the boat and the skipper and the mast gone. Incredible story of her survival Here is the book http://www.amazon.com/Red-Sky-Mourning-Story-Survival/dp/0786886765/sr=8-1/qid=1167858135/ref=pd_bbs_sr_1/105-7875417-7084405?ie=UTF8&s=books
Typical dismastings are due to simple rigging failures like broken tangs or cotter pins falling out. Sorry, I read the question wrong, I was trying to figure out (guess) what might have happened to that boat solo sailing that got dismasted If anyone read "Red Sky in Mourning" its a true story of a woman that lost her loved one overboard due to a "HUGE" wave that rolled their boat and just snapped the tether he was on. She came to a day later in the salon very groggy with about a foot of water in the boat and the skipper and the mast gone. Incredible story of her survival Here is the book http://www.amazon.com/Red-Sky-Mourning-Story-Survival/dp/0786886765/sr=8-1/qid=1167858135/ref=pd_bbs_sr_1/105-7875417-7084405?ie=UTF8&s=books
Moody:
You state some say to replace rigging evry 5- 7 years. Do you, as a rigger, think that is neccessary? What about fresh water boats? I took a 20 year old back stay used on fresh water into Plamer Johnson, and asked them to make me a new one because I thought it was time. They thought there was no reason to replace the stay.
You state some say to replace rigging evry 5- 7 years. Do you, as a rigger, think that is neccessary? What about fresh water boats? I took a 20 year old back stay used on fresh water into Plamer Johnson, and asked them to make me a new one because I thought it was time. They thought there was no reason to replace the stay.
What could have led to one...
Years ago, racing my Pearson 26 One-design in 15-20 knot gusting winds, we put the chute up (against my better judgement). We went through a series of two or three spectacular broaches, with the chute collapsing then refilling with a shock like an explosion. The last fill/broach easily outdid the others, with water pouring over the coaming. I looked up at the rig, water around my ankles, expecting to see the chute split to confetti. What I saw instead was the windward upper shroud swinging loose. Ugh, and thank goodness for stout mast sections. After dropping the sails and rigging a halyard to a stanchion base, I got a chance to look at the shroud. The rigging screw had snapped, and looking at the fracture it appeared it had been cracked halfway through for some time before. In short, I got away with one.
Years ago, racing my Pearson 26 One-design in 15-20 knot gusting winds, we put the chute up (against my better judgement). We went through a series of two or three spectacular broaches, with the chute collapsing then refilling with a shock like an explosion. The last fill/broach easily outdid the others, with water pouring over the coaming. I looked up at the rig, water around my ankles, expecting to see the chute split to confetti. What I saw instead was the windward upper shroud swinging loose. Ugh, and thank goodness for stout mast sections. After dropping the sails and rigging a halyard to a stanchion base, I got a chance to look at the shroud. The rigging screw had snapped, and looking at the fracture it appeared it had been cracked halfway through for some time before. In short, I got away with one.
My surveyor told me...
that in the northern areas he would consider replacing rigging around the 30 year mark. In southern climates possibly 15 years would be a more appropiate time. I specifically asked this question when he was doing a 10-year survey for my insurance company. However, he did say that yearly inspections (or more often) should definately be done. End fittings should be checked for cracks and signs of degredation. Wires should be checked for broken strands. Anything suspicious should be reviewed by a professional.
that in the northern areas he would consider replacing rigging around the 30 year mark. In southern climates possibly 15 years would be a more appropiate time. I specifically asked this question when he was doing a 10-year survey for my insurance company. However, he did say that yearly inspections (or more often) should definately be done. End fittings should be checked for cracks and signs of degredation. Wires should be checked for broken strands. Anything suspicious should be reviewed by a professional.
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