I have always been concerned with an accidental jibe and the consequences thereof. Can someone tell me the pro's and con's of using a preventer? Where are the most convenient points to secure the boom. Is it possible to create a dangerous situation by using one? Thanks
Use of a preventor
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Used one on an overnight race
We were going down the Bay and the wind was blowing stink. We had a preventer tied from the boom to a metal toe rail. It worked fine. It is a safer way to do things in heavier air. I don't see how you could create a dangerous situation by putting a preventer on.
We were going down the Bay and the wind was blowing stink. We had a preventer tied from the boom to a metal toe rail. It worked fine. It is a safer way to do things in heavier air. I don't see how you could create a dangerous situation by putting a preventer on.
preventers
Let me pass on these links, rather than ramble on in my own words. http://en.wikipedia.org/wiki/Preventer http://books.google.com/books?id=lI71GXRPELsC&pg=PA27&lpg=PA27&dq=rigging+a+preventer&source=web&ots=QpnxoZSiwT&sig=aESdSzaBurC7bzPEvRA56g_8ip8&hl=en#PPA27,M1 Here's an excerpt from a Cruising Log discussion: "There is a very simple technique for rigging preventers. From the end of the boom (or very close to it) a line is rigged on each side to a block forward of the mast from which it then leads aft to the cockpit. When the vessel is settled on a run, the preventer on the side of the same side of the boat as the boom is simply pulled taight and belayed on a cleat in the cockpit. Don't forget to let it go before tacking or deliberately gybing! The arrangement is simple and the cost almost negligable."
Let me pass on these links, rather than ramble on in my own words. http://en.wikipedia.org/wiki/Preventer http://books.google.com/books?id=lI71GXRPELsC&pg=PA27&lpg=PA27&dq=rigging+a+preventer&source=web&ots=QpnxoZSiwT&sig=aESdSzaBurC7bzPEvRA56g_8ip8&hl=en#PPA27,M1 Here's an excerpt from a Cruising Log discussion: "There is a very simple technique for rigging preventers. From the end of the boom (or very close to it) a line is rigged on each side to a block forward of the mast from which it then leads aft to the cockpit. When the vessel is settled on a run, the preventer on the side of the same side of the boat as the boom is simply pulled taight and belayed on a cleat in the cockpit. Don't forget to let it go before tacking or deliberately gybing! The arrangement is simple and the cost almost negligable."
Quick release
Make sure you rig it in a way that it can be released quickly. I have been sailing downwind in rough conditions when the wind changed direction 90 degrees without warning. Of course it was to the same side that the boom was secured. I was able to release the preventer to keep from loosing control which is very important in close quarters racing. I lead my preventer through a block along the toe rail back to a spare ST winch I have in the cockpit.
Make sure you rig it in a way that it can be released quickly. I have been sailing downwind in rough conditions when the wind changed direction 90 degrees without warning. Of course it was to the same side that the boom was secured. I was able to release the preventer to keep from loosing control which is very important in close quarters racing. I lead my preventer through a block along the toe rail back to a spare ST winch I have in the cockpit.
Hmmm
I haven't ever used one - which I'm guessing speaks more to the type experience I have. The danger to the accidental jibe turn is in the potential to cause head injuries and MOB, but also to cause a loss of control over your boat, right? My instinct tells me having two additional lines of rigging when a sudden wind shift occurs(as Tim described) would cause greater temporary loss of control than if the crew's head is low and the boom shifts in response to the wind. Additionally, it would seem that a sudden shift in wind would cause the boat to dip and heel opposite the side the preventer (more so than an accidental jibe because of the preventer rigging along the rail) until the situation was corrected. Like I said, I haven't had the pleasure of a preventer, but am I off base?
I haven't ever used one - which I'm guessing speaks more to the type experience I have. The danger to the accidental jibe turn is in the potential to cause head injuries and MOB, but also to cause a loss of control over your boat, right? My instinct tells me having two additional lines of rigging when a sudden wind shift occurs(as Tim described) would cause greater temporary loss of control than if the crew's head is low and the boom shifts in response to the wind. Additionally, it would seem that a sudden shift in wind would cause the boat to dip and heel opposite the side the preventer (more so than an accidental jibe because of the preventer rigging along the rail) until the situation was corrected. Like I said, I haven't had the pleasure of a preventer, but am I off base?
Boom brake
Preventer could be dangerous at certain situation. If space is available, a boom brake is a better shoice. It allow the boom to swing but slowly.
Preventer could be dangerous at certain situation. If space is available, a boom brake is a better shoice. It allow the boom to swing but slowly.
Preventer
An accidental jibe in moderate or heavy air can cause damage to your rig or boom, so it is more than just a crew safety issue. It really makes wing and wing sailing a lot more relaxing. One can go off the end of the boom, but it is sometimes more convenient to attach it mid boom, especially if you decide to put it on once your main has already been eased out for the downwind tack. I prefer a traditional boom vang type set up with fiddle blocks. This allows mechanical advantage to help control the boom should an accidental gybe occur. I use the same set up I keep on board for MOB events. One can also use any stout line pretty much just as well, tying it off to the toe rail of something else midship.
An accidental jibe in moderate or heavy air can cause damage to your rig or boom, so it is more than just a crew safety issue. It really makes wing and wing sailing a lot more relaxing. One can go off the end of the boom, but it is sometimes more convenient to attach it mid boom, especially if you decide to put it on once your main has already been eased out for the downwind tack. I prefer a traditional boom vang type set up with fiddle blocks. This allows mechanical advantage to help control the boom should an accidental gybe occur. I use the same set up I keep on board for MOB events. One can also use any stout line pretty much just as well, tying it off to the toe rail of something else midship.
Taming the Boom
David, You may wish to check the March/April 2008 issue of Good Old Boat magazine. There is an article at page 44 which tells in detail how to keep things under control with dual off-center vangs which also act as preventers. I plan to install these on my boat. The authors are experienced offshore sailors and the article is well-written and will be kept in my useful article library. This article alone is worth the cost of the magazine. Good luck, Pete
David, You may wish to check the March/April 2008 issue of Good Old Boat magazine. There is an article at page 44 which tells in detail how to keep things under control with dual off-center vangs which also act as preventers. I plan to install these on my boat. The authors are experienced offshore sailors and the article is well-written and will be kept in my useful article library. This article alone is worth the cost of the magazine. Good luck, Pete
Taming the Boom
David, You may wish to check the March/April 2008 issue of Good Old Boat magazine. There is an article at page 44 which tells in detail how to keep things under control with dual off-center vangs which also act as preventers. I plan to install these on my boat. The authors are experienced offshore sailors and the article is well-written and will be kept in my useful article library. This article alone is worth the cost of the magazine. Good luck, Pete
David, You may wish to check the March/April 2008 issue of Good Old Boat magazine. There is an article at page 44 which tells in detail how to keep things under control with dual off-center vangs which also act as preventers. I plan to install these on my boat. The authors are experienced offshore sailors and the article is well-written and will be kept in my useful article library. This article alone is worth the cost of the magazine. Good luck, Pete
Preventer also helps vang the main
With the main out as far as it should go, the preventer and the mainsheet are pulling down on the boom from fore and aft, helping the vang to hold it down. While running, the most likely time for the preventer. the following wind is diminished by boat speed away from it, so my experience is that if major shifts or big following waves allow the wind to get behind the main, the boat is stable enough to allow steering the wind back into the main. If a wave dips the end of the boom in the water, a preventer attached forward of the aft end of the boom can put enormous forces on the spar, even bending it. So I prefer the end of boom configuration. Our vang has snap shackles on both ends to allow easy use as a preventer. David Lady Lillie
With the main out as far as it should go, the preventer and the mainsheet are pulling down on the boom from fore and aft, helping the vang to hold it down. While running, the most likely time for the preventer. the following wind is diminished by boat speed away from it, so my experience is that if major shifts or big following waves allow the wind to get behind the main, the boat is stable enough to allow steering the wind back into the main. If a wave dips the end of the boom in the water, a preventer attached forward of the aft end of the boom can put enormous forces on the spar, even bending it. So I prefer the end of boom configuration. Our vang has snap shackles on both ends to allow easy use as a preventer. David Lady Lillie
I've rigged a Preventor
I rigged one using some snap shackles and pullys. It is attached to the same point as the mainsheet on the boom and to a cleat and a stanchion base. With the pullys I can pull the boom nice and tight and there is little movement . When tacking in heavy winds the boom is lowered to the leeward instead of getting blown around. I only use it at sea where the chance of a jibe due to wave action is greater. This arrangement does act like a boom vang to keep the sail flat. Some recommend keeping a sharp knife handy!!!!
I rigged one using some snap shackles and pullys. It is attached to the same point as the mainsheet on the boom and to a cleat and a stanchion base. With the pullys I can pull the boom nice and tight and there is little movement . When tacking in heavy winds the boom is lowered to the leeward instead of getting blown around. I only use it at sea where the chance of a jibe due to wave action is greater. This arrangement does act like a boom vang to keep the sail flat. Some recommend keeping a sharp knife handy!!!!
I use a simple 4:1
block and tackle shackled to a boom bale and then to the toe rail. I only use this preventer when I plan to sail a pretty long leg downwind. On a previous boat, I had a helluva time when the wind shifted quickly while going downwind with a preventer in place. I was lucky to be able to release the preventer quickly and use it to control the boom. Now whenever I have a preventer rigged, I always keep the bitter end of the tackle in my hand.
block and tackle shackled to a boom bale and then to the toe rail. I only use this preventer when I plan to sail a pretty long leg downwind. On a previous boat, I had a helluva time when the wind shifted quickly while going downwind with a preventer in place. I was lucky to be able to release the preventer quickly and use it to control the boom. Now whenever I have a preventer rigged, I always keep the bitter end of the tackle in my hand.
Sam As Higgs With Some Adds
I use a 4:1 tackle from a boom bail to the tow rail. I do a couple of long downwind races and it's a necessity. I do a couple of things differently: the lower block has a heavy rubber snubber line on it to both help keep tension on the boom, but more importantly, to give it just a bit of 'give' should the boom get wet or jibe. I also keep the cleating block up at the bail with the release downward and the tail led to the cockpit so that a single yank will release it. Booms can be dangerous. At night, about 100 miles south of Cabo san Lucas, in 20 knots of wind, my head was dealt a glancing blow by a boom as it swung during an accidental jibe when we got slapped on the quarter by a odd wave. The irony is that I was moving the preventer at the time. Keep your head down!
I use a 4:1 tackle from a boom bail to the tow rail. I do a couple of long downwind races and it's a necessity. I do a couple of things differently: the lower block has a heavy rubber snubber line on it to both help keep tension on the boom, but more importantly, to give it just a bit of 'give' should the boom get wet or jibe. I also keep the cleating block up at the bail with the release downward and the tail led to the cockpit so that a single yank will release it. Booms can be dangerous. At night, about 100 miles south of Cabo san Lucas, in 20 knots of wind, my head was dealt a glancing blow by a boom as it swung during an accidental jibe when we got slapped on the quarter by a odd wave. The irony is that I was moving the preventer at the time. Keep your head down!
when wind is up and shifty
i always hook up a preventor that is attached at the bail on the boom where the vang is attached.i then lead it to the rail and back to a secondary winch and cleated off . with this setup and a accidental jibe i can control the release easily. of course the key is not to let the boom go flying. I've used this setup for many years and never had a problem.
i always hook up a preventor that is attached at the bail on the boom where the vang is attached.i then lead it to the rail and back to a secondary winch and cleated off . with this setup and a accidental jibe i can control the release easily. of course the key is not to let the boom go flying. I've used this setup for many years and never had a problem.
Preventer
An awfully large percentage of injuries and even fatalities on larger sailboats are caused by accidental jibes, and they also have the potential to damage the rigging severely. It is also true that the risk is not only in high winds but can also happen in lighter and somewhat fluky winds, especially if you are sailing close to dead downwind and there is wave action that causes you to sail by the lees. The most important thing the preventer does is to keep the boom from starting to move, so that it does not build the tremendous momentum it can develop once it starts jibing. Many of the articles I have read suggest putting a weak link in the preventer rig, so that it in a situation where the boom goes into the water (as in broach), it does not cause more trouble, though I have never fully understood this. It always seemed to me that a weak link means that in a severe situation, the preventer won't prevent.
An awfully large percentage of injuries and even fatalities on larger sailboats are caused by accidental jibes, and they also have the potential to damage the rigging severely. It is also true that the risk is not only in high winds but can also happen in lighter and somewhat fluky winds, especially if you are sailing close to dead downwind and there is wave action that causes you to sail by the lees. The most important thing the preventer does is to keep the boom from starting to move, so that it does not build the tremendous momentum it can develop once it starts jibing. Many of the articles I have read suggest putting a weak link in the preventer rig, so that it in a situation where the boom goes into the water (as in broach), it does not cause more trouble, though I have never fully understood this. It always seemed to me that a weak link means that in a severe situation, the preventer won't prevent.
I use a boom vang
We get light winds out on Santa Monica Bay at times and I always worried about an accidental jibe. I was able to buy a used small boom vang and attached a couple of snap shackles on either end. Makes it easy to snap one end on the mast and the other end on the toe rail. Nice part about it is I can also throw it in an overnight bag and take it with me when sailing on someone else's boat, just in case they don't have one.
We get light winds out on Santa Monica Bay at times and I always worried about an accidental jibe. I was able to buy a used small boom vang and attached a couple of snap shackles on either end. Makes it easy to snap one end on the mast and the other end on the toe rail. Nice part about it is I can also throw it in an overnight bag and take it with me when sailing on someone else's boat, just in case they don't have one.
I'm with Karl..
...Except that what I do is unleash the boom vang line and hook it to the base of the chainplate. Easier and quicker, fewer parts. Hasn't pulled the base plate off yet, and when it does I don't want to look.
...Except that what I do is unleash the boom vang line and hook it to the base of the chainplate. Easier and quicker, fewer parts. Hasn't pulled the base plate off yet, and when it does I don't want to look.
The Dutchman boom brake is available here
http://shop.sailboatowners.com/detail.htm?fno=400&group=863 Dave Groshong Customer Service SailboatOwners.com
http://shop.sailboatowners.com/detail.htm?fno=400&group=863 Dave Groshong Customer Service SailboatOwners.com
It doesn't take much force to prevent an accidental Jibe
When I did a lot of single handing i Used my Vang from the boom to the base of the mast to keep the boom down, and permanently mounted preventers on each side to prevent accidental jibes. They consisted of a single line each from the boom forward of the companionway (so i wouldn't get caught in it when I jibed intentionally), through a block at the aft shroud base, and back to a cam cleat on my cockpit combing so I could release it quickly and easily. It usually worked just fine but on a couple of occasions I forgot it and Jibed anyway. It accents your jibe in a hurry an you end up heaving to with some serious alarm. But even that is correctable so all in all I would recommend it to using the vang to the rail. I like the Idea of sailing from the cockpit when I'm shorthanded.
When I did a lot of single handing i Used my Vang from the boom to the base of the mast to keep the boom down, and permanently mounted preventers on each side to prevent accidental jibes. They consisted of a single line each from the boom forward of the companionway (so i wouldn't get caught in it when I jibed intentionally), through a block at the aft shroud base, and back to a cam cleat on my cockpit combing so I could release it quickly and easily. It usually worked just fine but on a couple of occasions I forgot it and Jibed anyway. It accents your jibe in a hurry an you end up heaving to with some serious alarm. But even that is correctable so all in all I would recommend it to using the vang to the rail. I like the Idea of sailing from the cockpit when I'm shorthanded.
I don't bother with turning blocks
The preventer ( 3/8") goes from the vang bail through a shackle on the slotted toe rail than back to a horn cleat - I don't use any blocks since the thing is static and I just snug up without much force. I also used climbers rope which is somewhat elastic.
The preventer ( 3/8") goes from the vang bail through a shackle on the slotted toe rail than back to a horn cleat - I don't use any blocks since the thing is static and I just snug up without much force. I also used climbers rope which is somewhat elastic.
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