Farr 30 Flyer
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YACHT DESIGN Farr 30 IRC-Optimized Bowsprit Farr Yacht Design has designed a removable, IRC optimized bowsprit for the Farr 30 One Design. The bowsprit measures 1.79m from the stem, a length which was chosen after evaluating similar boats and determining that the increased downwind boat speed eclipsed the induced rating penalty. The bowsprit’s cross sectional shape was derived from FYD’s proprietary formula that minimizes aerodynamic drag without compromising structural rigidity. 3D modeling tools were used to ensure that the bowsprit conforms perfectly to the bow geometry. The tackline is routed through existing hardware on the bow, reducing the amount of additional hardware required. A single bolt per side attaches the bowsprit to the hull; the bowsprit is easily removed so that the boat can get back into its one design configuration. Competition Composites Inc. (CCI) is an authorized manufacturer for the new bowsprit design. CCI is a unique Canadian manufacturing business focused on designing and building composites products for various industries, especially for the boating market. For the past several years, CCI has been manufacturing our Farr 395 and Beneteau 10R rudder upgrades. The feedback from these boat owners has been very positive regarding the craftsmanship, feel, and performance of the rudder designed by FYD, and manufactured by CCI. CCI offers the new IRC-optimized bowsprit for $3,900 USD, not including packaging & handling. For more details and to order, please contact CCI at [email protected] or +1-613-599-6951. If you wish to speak with FYD, please contact us at [email protected] or +1-410-267-0780. Farr Yacht Design / 613 Third St., Suite 22, Annapolis MD 21403 , United States / FarrDesign.com Competition Composites / 251, 5th Ave. Arnprior, Ontario, K7S 3M3, Canada / FastComposites.ca 1 Performance Details The sailplan (Figure 1 on page 5) shows the general arrangement for the bowsprit Performance Details PERFORMANCEdesigned DETAILS for the Farr 30. Sail and bowsprit dimensions are listed on the drawing and The sailplan (Figure 1 on page 5) shows the general arrangement for the bowsprit are further detailed below in Table 1. The sailplandesigned (Figure for 1 on the page Farr 4) shows30. Sail the and general bowsprit arrangement dimensions for the bowspritare listed designed on the for drawing the Farr and 30. Sail and bowspritare dimensions further detailed are listed below on the in drawing Table 1 and. are further detailed below in Table 1. ISP 13.62 [m] STL/TPS 5.20 [m] JISP 13.623.32 [m] [m] SpritSTL/TPS Length from stem 5.201.79 [m][m] MaxJ imum tack working load 4003.32 [kg] [m] Sprit LengthTable 1from: Relevant stem Bowsprit Dimensions1.79 [m] Maximum tack working load 400 [kg] The sprit was designed to beTable long 1: enoughRelevant toBowsprit accommodate Dimensions a wide variety of downwind sails without incurring an unnecessary IRC handicap penalty. The bowsprit is not The spritdesignedThe was sprit designed wasto carry designed to be high long luffto enough be-load long codeto enough accommodate 0’s that to accommodate could a wide be varietyused afor ofwide upwinddownwind variety sailing sailsof downwind ,without but this incurring an unnecessarysailsails type without IRC is handicapnot incurring typically penalty. an favored unnecessaryThe bowsprit under isIRC IRC not since designedhandicap it must to penalty. carry be highmeasured luff-loadThe bowsprit as code a headsail 0’s is that not could be used for(insteaddesigned upwind sailing, of to a carryspinnaker), but highthis sail luff incurring type-load is not code a typically large 0’s thathandicap favored could under penalty. be used IRC since for upwind it must be sailing measured, but as this a headsail (instead sail of atype spinnaker), is not incurring typically a favoredlarge handicap under penalty. IRC since it must be measured as a headsail As(instead long asof athe spinnaker), sail midgirth incurring is greater a large than handicap 75% of penalty.the foot length, then all sails flown As longfrom as the the sail sprit midgirth will isbe greater rated than as spinnakers 75% of the foot and length, theref thenore, allonly sails the flown maximum from the sized sprit willsail be rated as spinnakerswillAs long affect and as therefore, thethe sail rating. onlymidgirth the Table maximum is greater 2 (shown sized than sail below) 75%will affect of thesummarizes the foot rating. length, Table two then2 (shownoptions all sails below) for flown summarizesthe two optionsmaximumfrom for the the sprit- sizedmaximum-sized will spinnaker. be rated spinnaker. as spinnakers and therefore, only the maximum sized sail will affect the rating. Table 2 (shown below) summarizes two options for the maximum-sized spinnaker. Option 1: Large Option 2: Smaller SPA [m2] 106.9 99.4 Option 2: Suggested Linear Dimensions: [m] Option 1: Large Smaller SLU 15.6 15.29 SPA [m2] 106.9 99.4 SLE 13.08 13.14 Suggested Linear Dimensions: [m] SFL 9.06 8.29 SLU 15.6 15.29 SHW 8.97 8.45 SLE 13.08 13.14 Table 2: Spinnaker Sizing Recommendations SFL 9.06 8.29 Two sailsTwo sizes sails are sizes given aresince given theSHW optimum since the solution optimum8.97 depends solution somewhat depends8.45 on the somewhat typical sailing on the profile typical of the boat. A largersailing sail will profile increase of downwindthe boat.Table running A 2larger: Spinnaker performance, sail will Sizing increase particularly Recommendations downwind at wider apparentrunning performance,wind angles. Therefore the largerparticularly sail is favored at wider on windward-leeward apparent wind courses angles. where Therefore equal parts the of larger upwind sail and is downwind favored osailingn are included.windwardTwo A larger sails sailsizes-leeward will are also givencourses increase since wherepeak the performance optimum equal parts solution in marginal of upwind depends surfing and somewhatconditions, downwind ason long sailingthe as typical the are sail is not overpoweringincluded.sailing the profile boat A andoflarger the causing boat.sail excessive will A largeralso heel. increasesail It willis expected increase peak thatperformance downwind this will coincide running in marginal with performance, downwind surfing running in the windspeedsconditions,particularly range asat from longwider 12-18 as apparentthe knots. sail is notwind overpowering angles. Therefore the boat the and larger causing sail excessive is favored heel. on Itwindward is expected-leeward that thiscourses will coincidewhere equal with downwindparts of upwind running and in thedownwind windspeeds sailing range are A smallerfromincluded. sail 12 will-18 more knots.A larger likely besail favored will (takingalso increase into account peak its handicap)performance on courses in marginal with more surfing upwind than downwind conditions, sailing, and as courses long as with the reaching.sail is not This overpowering is especially true the ifboat reaching and causingwithout spinnaker, excessive but heel. is also true if flying AIta smallsmalleris expected reaching sail willthat sail more thatthis is likelywill less coincide than be favored the maximumwith (taking downwind rated into size. accountrunning inits the handicap) windspeeds on courses range withfrom more12-18 knots.upwind than downwind sailing, and courses with reaching. This is especially In bothtrue cases, if reachingthe spinnaker without area spinnaker,(SPA) is the butmost is important also true suggested if flying a value. small The reaching detailed sail luff, that leef, is foot and mid girthlessA smallerdimensions than thesail shouldmaximum will more be selected ratedlikely besize. by favored a sail designer (taking to into ensure account that the its sail handicap) flies properly. on courses Table 3 (shown on the next page) displays the predicted downwind VMG performance versus the one design configuration. The with more upwind than downwind sailing, and courses with reaching. This is especially performancetrue if deltas reaching are shownwithout as spinnaker,percentage butspeed is alsogain, truei.e. percentage if flying a speedsmall reachingincrease over sail thethat one is design configuration.less than the maximum rated size. 2 In both cases, the spinnaker area (SPA) is the most important suggested value. The detailed luff, leef, foot and mid girth dimensions should be selected by a sail designer to ensure that the sail flies properly. Table 3 (shown below) displays the predicted downwind VMG performance versus the one design configuration. The performance deltas are shown as percentage speed gain, i.e. percentage speed increase over the one design configuration. Wind Speed Spin Option 1: Large Spin Option 2: Smaller at 10m [kts] 4 8.1% 6.2% 6 5.6% 4.0% 8 2.8% 1.6% 10 2.0% 0.9% 14 3.2% 1.2% 18 4.4% 2.4% 20 3.8% 2.0% 25 1.2% 0% Table 3: Downwind VMG Performance Delta CONSTRUCTIONConstruction DETAILS Details The bowsprit is carbon construction made in a female mold. It uses a single external The bowsprittack line, is carbon one removableconstruction through made in hull a female bolt permold. side, It uses and a a single simple external wire bobstay.tack line, oneIt was removable throughengineered hull bolt per using side, anda 400 a simplekg working wire bobstay. tack load; It was this engineered loadcase usingwas driven a 400kg by working the breaking tack load; this loadcase was driven by the breaking strength of the halyard sheave at the masthead. strength of the halyard sheave at the masthead. The hull requires very little modification, thus keeping installation costs and added weight to a minimum. The only piece ofThe new hulldeck requhardwareires requiredvery little is an modification upgraded clutch, thus to handle keeping the increasedinstallation tack costs line load. and Each added component of the bowspritweight assemblyto a minimum was designed. The only to boost piece performance of new deck without hardware compromising required on is cost an andupgraded weight. clutch to handle the increased tack line load.