talked at some length with the authors of the F-18 U S rules.
-they have done a very nice job ,and have numerous F-18 specific cat designs to choose from and dealer support that goes with it ,-
AGAIN -we did not create the present set of existing conditions for 20s in the U S ,-we are proposing solutions to remedy these various weights and sail areas in existing designs , often 60 LB crew weights and 20 LBs boat weight variations within the same one design .!!!
Web site =http://www.f18.nl/index.html?Frame_ClassRulesF18.html&ClassRulesF18.html
Other Formula classes use approx 20 sq ft of spin area to 30 lb different weight catagory . -with a jib increase of 6.5 sq ft .
Believe these are a good basis for weight catagory ,though we do sail mainly during summer months in predominantly lighter wind conditions, and would propose placing 6 sq ft differentials in the main in 30 lb increments of weight classification , along with a minimal 2 sq ft in the jib .
This seems to be a proven basis or starting point that may be revised in the classes future.-Will work on substantiating this in design , and refining it further as required .
Original earlier numbers were based on existing designs we wished to include , -but realize they were too far apart.
-Catagory one ,--as compared to catagory 2 Inter 20 class base model at 380 min boat weight , -av 330 crew weight ,-208 mainsail area , 53 jib ,-and 270 sq ft spin.
--Catagory one with an av boat weight or 410 and 330 av crew for a total of 740 would have 6 sq ft more in the main than the Inter base specs. -2 in the jib ,-and 20 sq ft more spin area.
-CATAGORY ONE -wgt=740 spin =290 main =214 jib =55
-CATAGORY TWO-wgt.=710 spin,=270 main= 208 jib=53
-CATAGORY #3 -wgt.=680 spin =250 main=202 jib=51
Cat #4 future -wgt 650 spin=230 main =198 jib=48
-Other rules proposed include the trade of sail area from main to jib only in equal amounts to allow sail plan variation and modification.
-All crews would be advised to target a total weight and sail area below max. allowed ,---full weights will be required rather than half as allowed per other classes as the 20s are a total weight class .
-The 18 and 16 Formula classes have exact specific definitions .
Would like to propose simplified rules in abbreviated form and allow future F-20 members to write more definiative specs , most likely evolving to a modified and developemental trophy scoring system.
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