I was told by 2 prominent people in this sport, who shall remain nameless, that I can hold down a larger modern sail than an older one...'old' say in my case 18-20 years ago. But what wasn't explained was how much power they provide and for arguments sake an old pointy top 7.0 has the same power as a 6.5 in a flat top?
Can someone explain, and for my education, how this is achieved? Let's use a 6.0m no cam sail from both eras, I use this size as from memory most larger sails than a 6.0 were fully battened with cams.
For example, does the twist off at the top of the sail (flat top) soften the gusts and spills excess air therefore one would be able to hold down a larger sail in comparison? Is the more modern sail from around 10 years ago to now offer the same amount of power but just more comfortable and easier to use?
Older sails are more powerful than modern sails of the same size. This is true. Modern sails have evolved to be more rangy. If you can imagine your old pin head 6 with an extra half a square metre of flat panel at the top that's roughly what modern sail are like. They also tend to be longer in the booms.
my opinion - i'd agree with NotWal. The older sails seem to be punchier in the low end and have quite good acceleration, but not-so-good stability in the gusts (therefore less range). As you suggested, I believe this all comes down to the floppy-leech tech that has become standard in most sails in the last ten years.
With the older sails, without the ability for the leech to twist off in gusts forces the sail to absorb the wind ultimately deforming the draft. Centre of effort moves back and it's a fight to keep the sail balanced.
This is an uneducated guess, but I think the extra (low-end) power the older sails seem to have is in the cut; favouring deeper drafts and fatter sections under the mast.
New sails = more controllable power and wider wind range. Not sure that they are necessarily more powerful, I remember an old NPryde 7m one of the most powerful sails I ever had, just had a very narrow wind range about 12 to 14 kts, 15kts plus and became uncontrollable. However I would suggest the foils of today would have to be aerodynamically more efficient and hence more usable power.
I have recently changed from 15 year old sails to recent ones.
The recent ones are much nicer to sail, have a wider wind range and are much more stable in gusts but are less powerful per square metre than the old ones.
I would think you'd need to add .5m in size to a new sail to get the same power as an older one. ie 5m old sail = 5.5m new sail ( .5m is in the square top for spilling the excess power and does not contribute to forward drive.)
Agreed ...... less power - partly due to twist - and much greater range.
However you are getting a Kona? If so, this may be relevant.
I see many of the dedicated longboard guys use old style sails. I seem to remember a discussion online in which some said the new sails don't suit longboards (can't see why? but anyway...)
Perhaps their use of old style sails is just to be more retro and authentic on their old Mistral Malibu's and Pan Ams and WS Onse Designs.... I dunno.
I also think they mentioned a sail, manufactured new, but with old style cut and modern materials, specifically for longboarders.
Regarding sail types on Konas. I tried old v. new, just to find out.
For recreational fun sailing, new (twist top) sails work with no problem. A 6.0 Tushy Storm and 7.0 Tushy Thunderbird give excellent planing performance in appropriate wind strengths. They add to that 'short board feel' once up and blasting, and retain modern sail forgiving characteristics in the gusts.
Old sails have more grunt in marginal conditions, and may help if racing, but otherwise the new sails FEEL better once up and blasting, and isn't that why people still like long boards?
New sails with loose leaches don't pump efficiently. A pump of the sail looks pretty much like a gust, to the sail, so it dumps it. Imagine rowing with a floppy paddle.
Longboarders who race in classes that allow pumping prefer older, tight leech sails in lighter winds.
Quite so jtw, but for recreational sailing on a Kona, especially in planing conditions, loose leech sails put a bigger smile on my face!
To answer your question look at the evolution, alot of it focuses on race sail technology since that has been the "cutting edge" with the technology flowing down to other sails. Generalising-
Old sails (pre 1990):
Long luffs
Tight leeches
Often full profiles controlled with lots of outhaul
Flexible fibreglass battens
These sails had the power high up in the sail which helped lift heavy boards out of the water. Quite narrow wind ranges but size for size extended their range lower (6m comparable to a 7m circa 1995 sail). Produced fantastic catapults [}:)]
1990-1995:
Long luffs
Very loose leeches
Shallow static profile, lots of negative outhaul to get some fullness into the sail
Very stiff carbon tube/rod battens (they broke lots) or crap fibreglass battens
Very stiff carbon masts (460's up around imcs 28)
2d seam shaping- lots of flat sail panels stitched together that were forced into shape by the wind
Explosion of the loose leech- lots of static twist (loose material that twists away) terrible bottom end but great top end. Kind of a transition period with freeride sails alot of the freeride sails used old sail technology or loose leech technology so they were either bottom end oriented or top end oriented. Alot of the sails from this period felt very stiff and sometimes a bit twitchy.
1995-1999:
Long luffs
Better understanding of dynamic twist but erring towards loose leech
Better understanding of seam shaping via 3d and broadseam
Great battens lots of carbon and quite durable
Masts became a bit softer
Most sails from this period were loose leeched still quite shallow profiled including freeride and wavesails. Generally top ended sails with a bit better bottom end/more forgiving than before.
1999-2004:
Short luffs (fat heads/flat tops)
Continuation of seam/twist understanding
100% carbon masts
1999 the pwa went big, lots of 10m+ sails. Shortly afterwards slalom died, thankfully formula was there to take it's place in sail development. The focus was on making big sails work in more wind with better handling. Still lots of quite flat sail profiles but some freeride sails going quite deep in profile to get good bottom end with the loose leech. Unfortunately alot of sails were made to a cost in this period also with alot of crap monofilm/materials used and a step backwards in battens.
New sails-
Shorter luff
Shorter booms
Better use of seam shaping
Better use of dynamic twist
Fuller profiles down low
Softer and rd masts
Approx 04 speed sailing took off again with lots of money spent on developing the fastest sails possible. From that the ultra wide luffs came back bringing better stability. Graduated luffs and shorter booms give better handling. Shorter luffs keeps the coe lower. All this enables sails to have fuller profiles which gives better bottom end and go in the lulls yet you can pull on the downhaul and the sail wont turn twitchy. The twist focus is to have sails that drive well yet twist off when required. Softer masts give the sail a more alive/forgiving feel.
So yes because of all of the handling benefits you can hold down a larger sail than 15 years ago AND it will also have better bottom end (approaching that of old pre-loose leech sails). Top end is better because the sail drives better through the lulls so you are maintaining a higher average speed.
Excellent mkseven!
Well that well and truly brings me up to date, very interesting indeed and answered lots of my questions that I haven't even asked yet but would have sooner or later! Thank you.
Two more questions though, if the new sails have gone to shorter luffs and shorter booms, which I assume would need shorter masts, where did all the sail material go? Is this where the notched clew comes in? Someone in the late '80s or early '90s tried this, I think it was De Vries with very little success. It could have been experimental, it was a long time ago.
Second question, approximately when did the "x-ply" start being used in mainstream main sail panels? I've been assuming x-ply is the transparent material with the reinforcing X string grid as opposed to tear-prone (exploding) clear mylar of old?
Thanks again for putting together that report, good stuff. I'm slowly moving into the 21st Century.
It goes into the leech (about 30cm the whole way up) and a little bit into the foot.
Inset clews is not a new thing, alot more development has gone into it and still is (checkout the gaastra vapor threads in gear reviews). Everything current has been seen before for that matter ie wide luffs etc. There have been no magical concepts in the last 15 years- it is the rest of the development that enables old ideas to work.
Xply- it's always been there, mostly in wavesails. I think aerotech was the first to make the majority of their range xply since early 00's. It's a selling point for less mainstream sails- loft, aerotech, ezzy. It's a pity the big companies don't use it more but it means they sell more sails long term. Laminates are becoming more popular in racesails because of their weight saving properties rather than longevity. Pretty sure North are the only brand that have produced a single panel laminate windsurfing sail (same as yacht sails).
I used to sail a 7.5m back in the 80's.Now my biggest will be 6.6m..maybe I can go bigger....food for thought
i htink something missing off your list mk is sail tension.
late 90's saw sail surface tension increase to control draft and increase speed.
it got to the point where you needed a car to downhaul the sails.
in my mind one of the biggest improvements with sails in the last 4 years other than dynamic twist increasing wind range has been the designers have figured out how to come up with a sail that requires less tension (feels more forgiving) and still keeps it's draft shape static under load.
Quite right gestie, it was (mis)implied under the continuation of seam and twist technology in that the biggest way I feel the improvements is you have a sail which retains tension and drives well yet twists off when required. It probably does deserve it's own mention since it is the designer's buzz word of the moment.
The others I didn't mention is luff curves, but these have altered in no specific direction. I guess modern high carbon content masts could enable an increased curve (more stability) since they are more responsive.
A designer could probably add a hundred other things, I just sail em I don't make em
I will say though there are some interesting things happening with sail design at the moment. My pryde rs racings surprised the hell out of me when i'd expected a sail which was a bitch to downhaul due to numerous reports of mast failure in the last 5 years. But on getting them found them the easiest to downhaul out of all the modern race sails i've tried 
- in fact I would say my 7.8 race sail is quite possibly easier to downhaul than my 5.3 wavesail. They do however use stacks of tension through the cam/battens, very different to what the others seem to be doing- I guess all that point loading must torture the masts.
I maintain there is no one single big improvement, more the biggest improvement is all those single (at times unsuccessful) bits coming together to make sails what they are now. Many of the concepts in modern sails had been tried and dropped at some point. In that it is hard to isolate any one thing such as tension keeping the sail stable under load when it's many things that have contributed to that- increased luff curve, better cam systems, stiffer battens, better seam use, better panel shaping etc.
My one critisism of modern sails- the battens are ****. They either break or we are given fibreglass ones where we should be getting carbon 
Is racing the ONLY reason to be using long boards? I think not!
I use one (Kona currently) for long distance cruising along cliff lines and around islands. (Safety is an issue so I carry split kayak paddles and have a method of paddling efficiently without derigging if stranded by lack of wind.)
In the 80's early 90's there was no option but to use 'old' tight leech sails, so I very much appreciate the wider wind and comfort zone of modern sails. On an average 20+ mile cruise the wind can flutuate wildly (next to nothing to force6) owing to cliffs or funneling effects down inlets. That's where the greater wind range of modern sails is a safety factor. And that takes precedence over outright speed.
In my opinion the obsession with racing, and the implication that that's all longboards should be for, is a mistake. Cruising is a extra activity for days when short boarding is out. It's a pity nobody tries to 'push' the concept.
Glad you also enjoy long board cruising Jonesmb.
One of the great delights (Scottish Coast, masses of Islands, tiny bays to explore, and big headlands) is unexpectedly coming across stacks with narrow tide race passages to wiggle through. That's when a smaller throwabout 7.0 sail comes into its own. You can stop and play!
On windier open parts the 7.0 readily pops the Kona onto the plane.G.P.S. 23.7 m.p.h. average on windy day. Not record breaking, but so what? I was singing my head off! (I use an 8.0 on light wind days, of course, but windy is more fun.)
I grabbed an old North Ezzy Elipse 5.0 from the back of my shed this week to give to someone. I had forgotten how different those mid eighties sails were. The luff length was 4.7m, there is no way to rig that on a 4m mast! Amazingly tough material and great colours... purple, pink and yellow.
So Rubby, when I sail my wave board and 4.2 (loose leech) in a gusty gale and surf, it should have camber inducers to help control the sudden blasts on the wave face?
( Err, you do sail and surf in strong winds, don't you?)
Rubby I did say generalising. I know there are big discrepancies in the timeline- in the last 30 years there probably would have been over 5000 different sail designs put into production so it's impossible to discuss all. Almost everything had been tried in the 80's/early 90's only to be dropped or visited again later.
You probably will find well designed old sails work better with older boards than new stuff since boards and sails were designed to match (old boards i'm refering to widepoint forward, heavy, mast track forward, floppy finned stuff).
UP, ART, Arrows all had a different agenda- their sails were produced to compliment production boards. Their focus shifted closer to normal brands over the years as production boards became better and lighter (and marketing didnt want them to be seen as just production brand).
Your North Sting is certainly not the earliest of loose leech designs. North had been using loose leech since the early 90's at least. 98 was towards the end of the IQ era which focused on draft/seam placement and sail tension. A few sail brands started producing almost too many different types of sails (north was one of them)- particularly when freestyle first arrived, these sails worked great in the relatively narrow range.
There are plenty of no-cam freeride and wavesails around with great range and stability. It's all about the overall design and to a lesser extent the quality/number/placement of the battens used. Also locked full profiles don't always mean better gust handling, many wavesails use the direct opposite and you can depower if needed.
Yep; it seems like a fantastic place.
I'm trying to work out when we can have a weekend there on the boards. I've got to do some mods so that we can carry camping gear, but it should work out fine.
I haven't gone overnight cruising on a board for a gazillion years and really must do it again.
talking about old sails, i have 4 going for $10 each.
5m,5.8m,6.5m+7.5m. all race from 1995--2005.
i was on a gaastra course slalom sail 6.7m a few weeks back from around 1994 i think.
the leach shook itself crazy, the centre of effort was moving quite a bit compared to new race sails. it was slower for topend and more tiring to use.
i do agree with Chris 249 that a smaller sail, rigged with a tight leach is nicer to use over a larger more downhauled heavier sail.
not many though would agree!
i hate the feel of large sails especially on too small a board. the board tends to slide rather than lift upwards and you end up fighting like hell to get upwind.
newer sails from 2004 onwards wave + race are heaps better than older sails.
as for longboards, the great benefit is if conditions turns glassy the centreboard can get you back upwind better than a formula board ever will.
Thank you for the reply C 249.I wasn't contradicting you since I realise you do 'push' long board usage. I was merely stating my own dissatisfaction at the way long boarding is perceived.
I think that of all the windsurfing I've ever done (since 1982) the long board cruises will forever be burned into my memory. Gallumphing along on a lovely smooth swell, watching the other side visibly nearing as the mast tip carves it's way through a mackeral type sky, is the nearest thing to heaven I'll ever experience!
As you say sir,each to his own way of doing things!
