#4435 - 12/02/01 03:13 PM
crew weight on the Inter 20
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old hand
Registered: 07/26/01
Posts: 800
Loc: MI
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-Since we are basing a class largely on Inter 20 specs , -not Hobies with narrow bows a 30 Lb heavier cat that is weight sensitive,smaller sail areas and no shutes , and not the Tornado with much smaller sail plan ,10 ft beam and added 800 ft lb average added righting moment as compared to the Inter 20 with its 8.5 beam ,the following is particularly relivant.
-This from a well known cat designer ---as follows
The parameter that will bring this discussion on crew weight to focus is "overturning moment to righting moment ratio". The overturning moment corrilates with sail area times the height of the center of effort above the center of bouyancy of the burdened hull. The total righting moment is the sum of the boat righting moment (boat weight X boat width/2) plus the crew's righting moment plus the skipper's righting moment. This ratio tells the tale as to the optimum weight for the boat. Boats designed with a larger number (ratio)favor larger people and boats designed with a smaller number (ratio) favor smaller. Boats designed with a larger number tend to become overpowered sooner (less wind) and boats with a smaller number are more controlable in stronger winds and will excell in stronger winds.
Designers have gradually increased this ratio by adding additional sail area , and now the addition of large spinnakkers ,in an effort to build faster boats at lower cost than the competition via higher sail area to weight ratio. This doesn't work if you can't hold the boat down, does it?
Remember the recent Olympic catamaran selection trials? The old boat 10ft wide with 237sqft of sail area beat all the new designs with more sail area including spinnakers but only 8.5ft wide. If you don't go up in righting moment as you go up in sail area, then you can't drive the sails to their capability and the boat moves out of the competitive weight range for normal weight people and it won't perform well in strong winds. . What's happening with the 'new boats' they are powered up with more sail area and no improvement in righting moment and the big people are favored.
Good Sailing,--end
-It automatically requires larger crew to sail the Inter 20 effectively . proven in natl's and numerous race results .
Thes boats are POWERFULL and can not be held down by small crew . Again we are basing a class largely on Inter 20 specifications ,--{huge sail areas } -
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Being 6,4 and 225 , do not want to exclude racing sailors from the 20 class to allow myself a perceived advantage , even though most larger people in N A have raced at a disadvantage in predominantly light air racing on smaller less powerfull cats with smaller sail plans for decades
-In racing the Inter 20 extensively both singlehanding at 225LBs with CRAM and distance racing in MI. and racing it at just under 400Lb crew weight in 2 Worrell 1000s ,-before that 2 on the Nacra 6/0. Several have commented on how they believe the Worrell is a heavy air race ,---WRONG ,--over 13 days and nights in 1000 miles you encounter every combination of wind strength mother nature can conceive. Surprizingly the largest gains are made in light air .This being my 6th Worrell 1000 this year in 02 it is very disturbing to read other comments on how they think the Worrell is only in heavy air when they have NEVER RACED ONE , it is 60 to 75 percent in lighter wind .-Even at near 400 LB crew weight we still excell on the Inter by powering up the main and positioning more weight to leeward on these large bouyant hulls required to carry shutes. -The best example in the Worrell this year was the leg sailing up to cape Hatteras , light air 5 to 8 mph. The first team to the Cape was GUIDANT -Rod is an excellent world class Aussie 18 skiff and cat sailor , -2nd there was Tommy Bahama --{Nigel and Alex } ---3RD To Cape Hatteras was us ,-TEAM SAIL for SIGHT , Dave and I at just under 400 LB crew weight , --Dave and I passed T B in the surf at the cape and popped into the lead for a time shortly after .--The point is weight is not the factor that most are used to on other types of cats ,--These are large bouyant POWERFULL cats that require large crews with their added righting moment to race them.-
.–Again I have raced the Inter both at 400 LB CREW WEIGHT AND SINGLEHANDED AT 225 lb CREW WEIGHT ,Having this wide a range of crew weights in distance racing has given some special insight on crew weight as it is applied to these already overpowered cats which actually favor large crews in any winds above 10 mph.
Again the best way to equalize crew weight is with a total crew and boat weight rule , but even this still favors larger crew , allowing them more righting moment in weight on the wire in that above 10 range.
-The Inter 20 has 15 more sq ft than its Euro counterpart , all of this is in the upper mainsail with a larger sq top. –With regular crew this cat flies a hull in 8 mph winds , when singlehanding about 5to 6 mph winds IN WHICH CASE ONE BECOMES COMPLETELY OVERPOWERED IN 10.
-The power of these cats with huge sailplans and the same beam as smaller cats with smaller sailplans automatically requires a large crew to hold it down and sail it at near its performance capabilities.
-This was best illustrated to me in sailing the RED FOX distance races with CRAM 2 years ago–racing singlehanded.
-The 20 mile distance race on Lk Charlivoix began well for me at the start port tacking out in front of the fleet of of about 15 I-20s and a few other cats in 5 mph winds on Sun. the 2nd leg back to Charlivoix.. I held the lead for some distance passing numerous boats that had started ahead in different classes .
About halfway through the 20 mile course the wind kicked in to about 15 with higher gusts . I cranked the downhaul untill the upper main was flat as a board and popped out on the wire keeping the Inter in perfect trim just skimming off the wave tops . -
One by one other Inters with normal crew weight begane to pass as I struggled to hold it down , by the end of the race more than 12 cats had passed even though I knew I had sailed technically perfectly and made no course errors.
-Again compare sail area on the Inter to the Formula 18 -its much smaller but has the same beam and righting moment ,
The only way to hold these larger more powerfull cats down is with LARGER CREW which they are already specifically designed for .
The best solution is a total boat and crew weight rule ,
This requires a comprehensive scale of total weights to sail areas , as opposed to the present Formula means of various jib and spin sizes per crew and corrector weights.
A total boat and crew weight to sail area rule is the best rules method of providing equal FAIR sailing for ALL.
Carl
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#4436 - 12/02/01 06:18 PM
Re:total weight rule example
[Re: sail6000]
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old hand
Registered: 07/26/01
Posts: 800
Loc: MI
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-Hopefully now most comprehend the fact that all FORMULA CLASSES are developemental to some degree, and the need for sail area to weight applied . To what extent and how this weight and sail area rule should be constructed is now hopefully the discussion .
A claim may be made that a Formula Class with a total boat and crew weight rule is in effect more fair in that regard as it includes equal total weight -which even one design does not address other than a min. The downside is it requires a list of weights and sail areas just as the other Formula Classes .
This list for the 20 class is broader and cleans up the remedy for crew weight by combining and addressing it in the basic FORMULA, -while also including the wide array of existing active racing 20s , existing iF -20S like the Fox, and new HP 20s , lighterweight in design in its scope.
-Base specifications for the class are Inter 20 rounded down in weight -to 380 min boat weight with av 330 crew to a total of 710 LBs.-Again crew weight becomes less revevant as total weight is adjusted by total sail area in main jib and spin respectively per ISAF and Texel ratings in each catagory ,-with added class definition as to rated applied sail area limitations of configuration .
Inter 20 =-Sails-- mainsail 208 -Sail jib 53 -sail ar spin =270
-In example as we progressed up the scale in a total boat and crew weight to sail area rule to include iF Cat designs like the Fox and most existing active racing 20s in the U S like the H-20 and N-6/0 at a min 410 boat weight with av 330 crew to a total 740 LBs would be allowed =
-have not run these yet in ISAF or TEXEL and will adjust , but for example purposes , -an increase of 1 jib 3 main and 10 sq ft of sail areas in jib main and spin for each 10 Lbs would allow all cats in this 740 catagory a 56 jib ,217 main inc mast -and 300 spin .
Trade offs from main to jib area to be allowed for design variation and modification . -Note ,-larger jibs are especially effective in combination with spin poles set lower , effective area can be added lower to the pole with a low C E or as the existing N A Nacra 6/0 already has though using a foil.
-Example applied to the nacra .
Esisting main -197 jib -67 spin=300+
allowed main 217 -jib 56 -spin 300-
note trading off the existing jib of 67 =11 from main = 206 max. and is 197 now or just 9 sq ft difference. .
-The process now is to verify an exact scale coresponding to ISAF and TEXEL rating , then applying this formula to each existing design with potential modification to each , {as per example }and as applied to existing iF 20 designs like the fox , though rumor is it may lighten its boat weight . Then apply this rule to potential new HP designs and study the effects and feasability .
working on it -help
Carl
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#4439 - 12/02/01 11:37 PM
Re: Formula
[Re: sail6000]
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member
Registered: 11/13/01
Posts: 195
Loc: Texas
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Carl
We have talked about this before on several occasions. As we have agreed that it might be a good formula for sailors who are already envolved in the class in some for. It is not good for sponsors or converts as it allows for too many class divisions in an event, too much equipment for crews that change on a boat (IE one skipper that has multiple crews = multiple sail sets for varying weights), and it is too confusing for the officials to keep track of and therefore adjust for divisions. It leaves open a wide array of percieved adn probably actual cheating scenarios and finally is too complex for the average public to follow and therefore leaves potential sponsors cold.
The best way is as Mike Hill suggested regulate the sail area and keep up the crew weight. THis way we close the gap to a 40-50 lbs difference between boats all up and therefore make the sport more competitive for head to head racing. Remember the basic concept is to run the formula as first to finish first to win. Not a mathematical formula that is too difficult to explain to a sailor much less a spectator.
Trying to keep it simple for the public.
Steve
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#4441 - 12/03/01 02:02 PM
Re: simple for ALL
[Re: majsteve]
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old hand
Registered: 07/26/01
Posts: 800
Loc: MI
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Hi Steve -
great work with contacting potential sponsors and boat builders.
-All Formula classes are developemental , and all have a sail area to weight variable Formula in some aspect of rules with the goal of equal fair sailing for all .
-As Mike noted sail areas have to be defined , otherwise the rulebeater scenarios previously stated occur ,--then absolutely no sponsor or spectator will understand , and very few will even desire to partisipate.
Again a better vehicle for the sponsored racing at the top level of the sport would be one design , just as we did in Prosail , on Hobie 21s , If we have a class for ALL sailors it will not suit those specific requirements , though as it is proposed a better faster form of 20 ft cat will evolve from it for the top level racing that will as explained in the previous post abosulely require LARGER crews to race them effectively.--{see designers comments and righting equation}
-The other aspect of setting a 350 min is that it does not allow for equal fair sailing unless you weight 350 to 370 . As you say there is no allowance for variation of crew , and under this 350 rule scenario if you weight 400 your at a 50 LB disadvantage , -If you weight 320 you are completely excluded from racing 20s altogether , -Evan the average 170 LB guy has to have a 180LB guy to sail with ,or carry dead weight. What flexability is allowed here ?
It does not allow for variables in boat weights .
With this 350 min you have eliminated all junior sailors from competition , most all women sailors , a large majority of existing sailors not being able to meet weight , and worse have disadvantaged the heavier near 400 LB teams . A better solution is required that is fair to all .
-The proposed sail area to total weight rule DOES allow and factors in total boat and crew weights through the entire range .
-Again all other existing Formula classes have weight and sail area charts , but they pertain to crew weight . This rule combines boat weight and crew weight and cleans up the basic FORMULA TO INCLUDE ALL boats and types / sizes of crews .
--The specific scenario of changing crew weight to an extreme ,-{which most racing sailors do not do }.
Racing sailors will look at the rules -{total boat and crew weight to sail area } -find their boat and its weight add their crew weight , just as they do nowfor one design , then find sail area on the chart ,-again based on similar existing 20 ft designs. -Based on this they purchase a new boat per total weight or modify their existing boat if needed , {not all will}-skippers that change crew through a wider range say 50 LB , could either carry weight to meet the sail area per chart or have a 2nd spin of larger area , just as other Formula classes prescribe, and accept a slightly smaller main or larger with weight.
This is not complex or difficult to understand , -
Certainly very simple as compared to comprehending a 12 meter rule for the Ameriacas Cup , -A simple chart scale ,just as other Formula Classes have ,but applied to total crew AND boat weight.
The cheating aspect you mention can unfortunately occur anywhere .-We label all sail areas by the tack on each sail next to the sailmakers logo and have them label all new sails clearly per size in 2 inch numers easily reeadable and all crew similarly list their weight in large easily readable numbers , I believe in the honor system ,but any challenged and found in error would be DSQ.
-THE BEST ASPECT OF THIS RULE is beyond being fair and equal to all 20 sailors is that it allows existing and older boats to become part of the FORMULA 20 class , --this is unlike the other Formula classes in existance which seem to require new formula specific boats to compete. -
-Any can modify a 20 or take a 20 platform refinish it add some sails and race . This will encourage entry level racing and hopefully newer younger sailors ,without deep pockets to join in . Existing sailors that desire a new lighterweight 20 in a few years will make the existing boat available to more potential racing sailors . A number will take older excellent platforms and hulls like the light Tornado and build a Formula 20 , fun stuff .
As a class we will have to set up an active site for new and used parts, boards, masts suppliers , and especially sails and spin new and used in various sizes, Rick already has an auction board and classifieds set up . -
-Carl
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#4442 - 12/03/01 02:09 PM
Re: Formula
[Re: mhb]
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member
Registered: 11/13/01
Posts: 195
Loc: Texas
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Marc,
Let me be real direct here. Anytime you vary any setup for what ever reason it raises questions. Anytime you have identical set ups it does not.
Yes, I do care about this class. I have been working to make sure that it has something that no other class today has (including hobie). --- Viable corporate sponsorship, IE money.
If you look at sports as a business anytime that the organizational body has structured itself for corporate interaction it has been successful. Sailing is the only sport that has totally screwed itself in that area. It comes directly down from USSAILING and how it interacts with corporate amercia. DO you know that USSAILING does not even endorse the AMerica's cup campaigns? Most people don't. Yet it is the biggest draw that people have to our sport and has been existance for more than 150 years. Our country's leading organization is the only one that does not back our sport with its "national pride" yet its existance is chartered by Congress to do so. So for all you guys that want to work around USSAILING with another national organization -- sorry you still have to deal with USSAILING.
Marc, my point here is that I love this sport and that we as sailors need to make a stand to force reality into our sport,
If we design rules that are really simple (so even a moron can understand them) then we can get corporate sponsorship and show these dumbass monohullers how this sports needs to change. Which in my humble opinion will help revive sailing in general.
So for me it goes way past just a few pounds on a boat. I'm looking at the bigger picture here.
I did not take you comments as a personal attack. Please do not take these as such. I do have almost weekly contact with companies that want to do something (because they are headed by sailors and agree with my arguements) to help. All of these companies can move dollars into our sport in excess of what hobie and PC makes a year in gross sales.
THanks
Steve
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#4444 - 12/04/01 12:00 AM
Re: Formula
[Re: mhb]
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member
Registered: 11/13/01
Posts: 195
Loc: Texas
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Marc
What the Hell is your agenda? This is formula racing multiple builders building thier designs to box rules. Which is exactly what I am proposing. No changes for anyone. PERIOD.
The formula is what it is. And it is not one design! I am so tired of hearing that BS. I have stated various times that for a clear understanding simple is better. And that is what I am saying here.
I have not taken offense to anyones statements or thoughts. But the last one you made definitely offended. Just because we disagree on an issue (weight) that is not a reason to chuck it into a "go somewhere else" statement.
Marc, your building a boat if memory serves me correctly. What about this upsets your plans?
Steve
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