I'm pretty sure I know the answer but wanted some clarification. On the 35.5 Legend which sail provides the power. My thinking is that it's the main but wanted to be sure.
Which Sail is the "Engine"?
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I had this same question and ran it all the way to the Navy College, USCG, colleges, & sailing schools. The best answer I got was explained this way. The main sail WAS always thought to be the main driving force behind sailboats which is why they called it the main. But this was the old way, long before jibs were made 90%, 120% 150% & so on. A sail (ALL SAILS) produce .2 horsepower per square foot based on 5knt wind & the horsepower produced increases the same as speed increases (to the power of 4 as wind speed doubles). NOW it is said, whichever sail has the bigger area is now the main power sail. You can easily see boats on the weekend under jib alone easily passing other boats w/ just a main up (same size boat). That's because the area of the jib on boat 1 is larger then the area of the main sail on boat 2. So on boat 1, the jib produces more power, therefore boat 1s main sail engine On boat 2 (if the jib is below 100%) the main produces the most power.
I had this same question and ran it all the way to the Navy College, USCG, colleges, & sailing schools. The best answer I got was explained this way. The main sail WAS always thought to be the main driving force behind sailboats which is why they called it the main. But this was the old way, long before jibs were made 90%, 120% 150% & so on. A sail (ALL SAILS) produce .2 horsepower per square foot based on 5knt wind & the horsepower produced increases the same as speed increases (to the power of 4 as wind speed doubles). NOW it is said, whichever sail has the bigger area is now the main power sail. You can easily see boats on the weekend under jib alone easily passing other boats w/ just a main up (same size boat). That's because the area of the jib on boat 1 is larger then the area of the main sail on boat 2. So on boat 1, the jib produces more power, therefore boat 1s main sail engine On boat 2 (if the jib is below 100%) the main produces the most power.
Which sail
has the most power is determined by the design of the boat. Some boats are foresail driven and some are main driven. My C&C 38 was foresail driven. The Hunter 40 I have now is main driven. Both boats are mast head rigged. It is the size of the fore triangle that counts. Which is determined by where the mast is placed fore and aft on the boat by the design team. Not the % of the fore triangle that is used when making a sail. A 90% jib may be bigger on one 38' boat than a 100% or 110% on another 38' design. So the % of the fore triangle is only important when talking the same size fore triangle boats. Vinny
has the most power is determined by the design of the boat. Some boats are foresail driven and some are main driven. My C&C 38 was foresail driven. The Hunter 40 I have now is main driven. Both boats are mast head rigged. It is the size of the fore triangle that counts. Which is determined by where the mast is placed fore and aft on the boat by the design team. Not the % of the fore triangle that is used when making a sail. A 90% jib may be bigger on one 38' boat than a 100% or 110% on another 38' design. So the % of the fore triangle is only important when talking the same size fore triangle boats. Vinny
Hugh
While I like Morning Glory's post and it certainly sounds reasonable, I would suggest that the answer is different with each different sailboat, sail plan, and point of sail, as Vinny suggests. For a slope rigged boat, try taking the boat out in about 15kts of wind; put up the jib only, trim it on a close reach & sail for about 10 minutes. What's the boat's average GPS speed over the ground? Now furl the jib, raise and trim the main on the same close reach under the same conditions. What's the average GPS speed with the main? In my experience, with the above conditions, (whether cruising or racing) the boat (even a Hunter with a fractional rig) is almost always faster with just the jib compared with just the main. Downwind is a different story as would be boats like 12 meter monsters with huge mains and relatively small jibs. Curious to hear others experience
While I like Morning Glory's post and it certainly sounds reasonable, I would suggest that the answer is different with each different sailboat, sail plan, and point of sail, as Vinny suggests. For a slope rigged boat, try taking the boat out in about 15kts of wind; put up the jib only, trim it on a close reach & sail for about 10 minutes. What's the boat's average GPS speed over the ground? Now furl the jib, raise and trim the main on the same close reach under the same conditions. What's the average GPS speed with the main? In my experience, with the above conditions, (whether cruising or racing) the boat (even a Hunter with a fractional rig) is almost always faster with just the jib compared with just the main. Downwind is a different story as would be boats like 12 meter monsters with huge mains and relatively small jibs. Curious to hear others experience
clearing up what I ment
I agree vinny. You've cleared up what I was trying to say. The % I spoke of wasn't the foresail area, it was in error the % in relation to the main sail. You are right and that's what I was meaning. Whichever sail has more area = more power as long as it's trimmed right & the same basic shape as the other sail you're comparing it to. So you can't look at the area of a moderen jib and compare it to the cloud of canvas a square rigger flys.
I agree vinny. You've cleared up what I was trying to say. The % I spoke of wasn't the foresail area, it was in error the % in relation to the main sail. You are right and that's what I was meaning. Whichever sail has more area = more power as long as it's trimmed right & the same basic shape as the other sail you're comparing it to. So you can't look at the area of a moderen jib and compare it to the cloud of canvas a square rigger flys.
Depends whether it is a mast head rigged
(the head sail) or a fractional rig (the main). Obviously this is a general observation and may vary from design to design. Back in the 70's and 8o's designers used large genoa headsails and high aspect mains. A high aspect main was tall (luff)but not very wide (foot and leech). Starting in the 90's we start seeing small headsails and large mains like with the no backstay Hunters and hughe roach sails. Your legend 35.5 is considered to be main driven but when your sailing under jib alone, what is your engine? I would tend to agree with MORNING GLORY that both sails contribute to moving the boat. The other day I heard or read that a sailor claimed his boat moved as it was being pulled by the sheet coiled around the winch and after thinking about decided he was correct and an interesting way of looking at it.
(the head sail) or a fractional rig (the main). Obviously this is a general observation and may vary from design to design. Back in the 70's and 8o's designers used large genoa headsails and high aspect mains. A high aspect main was tall (luff)but not very wide (foot and leech). Starting in the 90's we start seeing small headsails and large mains like with the no backstay Hunters and hughe roach sails. Your legend 35.5 is considered to be main driven but when your sailing under jib alone, what is your engine? I would tend to agree with MORNING GLORY that both sails contribute to moving the boat. The other day I heard or read that a sailor claimed his boat moved as it was being pulled by the sheet coiled around the winch and after thinking about decided he was correct and an interesting way of looking at it.
I think Don got it right, IMHO...
head rigged the genoa is usually a larger sail and derives more power than the main. Fractional, the main is usually larger and derives more power, generally speaking. Of course there are always exceptions. Terry
head rigged the genoa is usually a larger sail and derives more power than the main. Fractional, the main is usually larger and derives more power, generally speaking. Of course there are always exceptions. Terry
Fred,
Her name's Charlie, she's crew ! I just have a hard time getting her to keep her clothes on. What am I gonna do; any suggestions ?
Her name's Charlie, she's crew ! I just have a hard time getting her to keep her clothes on. What am I gonna do; any suggestions ?
think about before you buy
but heres a link to buy it. hope it helps. ie you need to be licensed to buy and apply it due to the harmful affects on nature.
but heres a link to buy it. hope it helps. ie you need to be licensed to buy and apply it due to the harmful affects on nature.
I think that last reply was just advertising
I have no idea what bottom paint has to do w/ sail power, trim, etc. It looks like a misprint reply or just someone trying to do advertising.
I have no idea what bottom paint has to do w/ sail power, trim, etc. It looks like a misprint reply or just someone trying to do advertising.
Hugh
It's really very simple. Which is larger? on a frac rig the main is bigger on a masthead the headsail is. But in either case, both generate power. Trimming them both to work together is the key to performance. Understanding how and why to pull the strings is the key to success.
It's really very simple. Which is larger? on a frac rig the main is bigger on a masthead the headsail is. But in either case, both generate power. Trimming them both to work together is the key to performance. Understanding how and why to pull the strings is the key to success.
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