Blurb with Deep Ww Foil
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VOLVO PROA !1 SPECIFICATIONS Weight: 480 kgs Sail Area: 66 sq m Length: 15m Mast height: 20m above water Beam: 8.4m Frontal Area: 8.8 sq m at 25° apparent while foiling, excluding rig and rudders Wetted Surface: 12 sq m when floating including hulls, foils, rudders Righting Moment: 7,240 kgm when flying Draft rudders up: 0.2m Draft rudders down: 1.75m Shipping: 3 shipping containers for 8 boats Cost: 150,000€ GENERAL DESCRIPTION The numbers refer to items in the following drawing, page 3. 1) The triscarph configuration reduces weight, cost, wetted surface and drag. 2) Rudders at 30% and 70% of the length provide leeway resistance and faster steering than stern mounted rudders. 3) Foils plug into the bottom of the rudder to enable changing foils afloat and simplify repairs. Foil lift is controlled by wands linked to the foils. 4) The foil under the windward hull automatically rotates to follow the direction the boat moves in. 5) The crew hull is always to windward and all sail controls lead to it. Once the sail is up, the crew do not move from the windward hull except in wind below 6 knots. 6) The single main sail is large enough that no extra sails are required. The 20m mast puts sail area above the turbulence and wind shadows in sheltered venues and ensures hull flying in 6 knots of breeze. 7) The two piece mast slots together and is raised and lowered sideways (canted) using the sheet winch. 8) The wishbone boom extends in front of the mast where it attaches to the forestay. Leech tension tightens the forestay, keeping the mast straight. A lever on the diamonds provides 30:1 purchase from the cockpit. 9) Washboard for easy guest access and padded stool for him/her to sit on. 10) Trampolines in carbon rod frames attached to the beams with quick release buckles. 11) Removable soft ends to limit impact damage. 12) Remote controlled camera to view the sails, foils, crew and other boats without risk of damage from crew, sheets or sails !2 OVERVIEW 6 7 8 3 12 10 11 1 2 3 5 4 11 3 9 !3 SHUNTING Unlike conventional craft which tack and gybe, the Volvo Proa shunts. The rudders rotate but the boat remains angled to the wind. Once the rudders are pointing upwind (tacking) or downwind (gybing), the sail is sheeted to the opposite end. The hulls do not have to point into the wind with the associated drag and both the steered rudders on the lee hull and the auto aligning rudder on the windward hull rudders are always aligned with the water flow. Consequently the boat stays on the foils for longer. The faster the sail is sheeted to the other end, the higher the likelihood of staying on the foils. For most of the shunt, the main is weathercocking towards it’s new position so sheet loads are low and sheet speed is key. To facilitate this, the mainsheet is a 1:2 system. The main is self vanging, so the sheet loads are relatively low, the #40 winch handles the fine trim at the end of the shunt. Shunting is millennia old, yet only in the last couple of years have rigs and techniques become fast enough to make proas viable in short course racing. Professional sailors will not only learn it quickly, but improve it as well. DOWNWIND SHUNTING (page 5) Foil shunting is done quickly. The rudders are turned through 180 degrees as quickly as possible. The red one starts turning first to initiate the turn and again after the rudders are pointing downwind. When the platform is at right angles to the wind, the sail is sheeted on as quickly as possible to keep the power on as the boat bears away onto the new course. The rig can be raked forward to assist with the bear away. If VMG>TWS at step 3, continue foiling dead down wind until VMG<TWS UPWIND SHUNTING (page 6) The rudders are turned through 180 degrees as quickly as possible. The red one starts turning first to initiate the turn and again after the rudders are pointing upwind. As soon as the platform is at right angles to the wind, the sail is sheeted on as quickly as possible to keep the power on and luff the boat onto the new course. !4 DOWNWIND SHUNTING !5 UPWIND SHUNTING !6 VOLVO INSHORE FOILER PRICES AND WEIGHTS SUMMARY Prices are Australian labour and materials converted to Euros at 0,68 Platform, Spars, Rudders Materials 9 748 Platform, Spars, Rudders Labour 74 800 Build Hours incl fitout 1191 Consumables @ 25 Euros per sq metre 2 433 Fittings and fit out materials 44 046 Fittings and fitout labour 6 188 Mould amortisation assuming 8 boats built 6 795 Design fee 5 000 COST OF BOAT in container 149 011 Euros WEIGHT OF BOAT ready to race 480 kgs PLATFORM, SPARS, RUDDERS Surface Weight Foam carbon resin Paint Labour Area 10mm H80 uni/db kgs 3 coats hours Windward hull, floor and bhds 300/10mm/300 plus 20% overlaps and reinforcing21 52 13 15 16 8 120 Lee Hulls 450/10mm/450 plus 20% overlaps and reinforcing 23 68 14 24 21 8 160 2 x Athwartship Beams 23 70 41 21 9 160 Fore and aft beam lee hull 11 24 13 7 4 80 3 x rudder shafts and foils 2 56 37 19 1 80 3 x rudderblades 450/10mm/450 + uni 2 6 2 2 2 1 200 Boom 300/10mm/300 + uni 6 18 11 5 2 60 Mast incl integral fittings 10 88 56 28 4 240 Totals 97 383 29 199 117 36 1100 Unit cost 34 32 10 34 68 Total cost 1 002 6 308 1 198 1 241 74 800 Notes: resin:fibre is 1:2 by weight, plus 300 gsm per side for the foam FITTINGS AND FIT OUT labour Rate materials weight cost source 68 Sail, cars and battens 25 160 30 25 160 North Brisbane Stays 44m 8mm dyneema 4 272 269 2 541 Strong Ropes 1273 Halyard (36m x 3m), sheet (22 x8), diamonds (26 x 6, 20 x 8) 4 272 432 4 704 Strong Ropes Outhaul (20m x 8 mm), downhaul (12m x 8mm) 2 136 65 3 201 Strong Ropes Diamonds adjuster, mast collars, spreaders, mast head, boom ends 8 544 612 6 1 156 in house 2 x #40 winches 1 for main sheet, 1 for sail and mast control 1 68 2 795 14 2 863 whitworths less 30% 4 x Power clutches for cant and rake, 6 x cam cleats 2 136 1 605 5 1 741 whitworths less 30% 24 turning blocks (18 plus steering) loop tied to beams and boom 1 68 1 900 5 1 968 Karver KB010 trampolines 2.2m x 7m, 40 straps, 20m 10mm rod frame 5 340 802 9 1 142 net systems 2 x steering wheels, mounts, quadrants, 60m 3mm dyneema 20 1 360 1 862 9 3 222 Jefa 6 x rudder bearings 10 680 8 000 10 8 680 Jefa 2 x wands and linkages 20 1 360 136 2 1 496 various Trolleys 10 680 340 1 020 in house Packing in container 4 272 68 340 Total 91 6188 44046 97 50234 MOULDS Plug and Mould OR Mouldcam OR 3d printed Hours Rate materials shipping not incl 816 per sq m 68,00 estimares Mast incl track, head, base, collar, sleeve 240 16 320 1 360 13 226 8 455 Lee hull ADDRESSING THE120 TENDER8 160 CRITERIA680 26 407 9 220,8 Windward hull half mould 240 16 320 1 020 13 203 8 568 fore/aft beam 120 8 160 680 3 597 8 976 athwartships beam 120 8 160 340 9 893 9 302,4 Therudder key objective is to produce a racing platform200 13 600 designed340 to test and3 591 excite elite1 632 foils 120 8 160 340 1 796 816 levelboom sailors and deliver high performance 120 8 160 340 5 396 2 448 Miscellaneous small moulds (10% of total) 128 8 704 510 7 711 4 942 The 15m/ 50’ Volvo Proa is one fifth the weight1408 65 of 106 the AC5 610 50 (480 kgs vs ~2,400) with two Total mould costs 70 716 84 821 54 360,8802 thirds the sail area (66 sq m vs 100). It is easier to sail, rig and maintain and will fly a hull andPer boat, foil assuming in 6 8 knots of breeze. In 30+ knot winds it will be8 839able to race,10 603 not just6 survive.795,110025 COST PER BOAT 6 795,110025 PERFORMANCE NUMBERS Weight of boat incl 5 x 90 kgs crew and guest 930 kgs Wetted Surface floating 11 sq m Weight in ww hull incl 2 x 90 kg crew 267 kgs Windage when flying, 25˚ AWA 9 sq m Weight in ww hull incl 5 x 90 kg crew 537 kgs Sail area 66 sq m Centre line to centreline beam 8 m Minimum righting moment 5114 kgm Maximum righting moment 7163 kgm height of coe 10 m Apparent windspeed to fly a hull, 3 crew to leeward 8 knots Foiling. Approximations, to be tuned when final weights etc are known. Lift off speed 10 knots m/sec 5 m/sec lee hull weight incl 3 people 663 kg Newtons 6498 N CL of foil 1 water density 1025 kgs Area = W/0.5 x CL*density*speed squared.