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Asymmetric Sailing Some secrets Andy Howard Llandegfedd Sailing Club
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Downwind speed? What’s the fastest theoretical speed you can sail directly downwind? Slide 2 Andy Howard Llandegfedd Sailing Club
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Downwind speed? Max theoretical speed straight down wind has to be wind speed – otherwise what is pushing you? So - how do you go faster? Slide 3 Andy Howard Llandegfedd Sailing Club
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Polar Diagrams - 1 Slide 4 Andy Howard Llandegfedd Sailing Club Typical RYA teaching diagram No go zone
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Apparent Wind - 1 Boat goes at 5 mph in 10 mph cross- wind Vector addition shows 11 mph wind at 27° away from true, 63° from bow This means as you speed up you trim the sails as the wind moves forwards Slide 5 Andy Howard Llandegfedd Sailing Club wind boat Apparent wind
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Apparent Wind - 2 Boat goes at wind speed 45° from downwind (say 10mph) Complex trig – (subtraction) shows wind is still in front of boat, 65 from the bow° The apparent wind speed is now 7.8 mph You should bear away to go faster! Get wind across the beam Skiffs go much faster than the wind – even more pronounced effect Slide 6 Andy Howard Llandegfedd Sailing Club wind boat Apparent wind
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Apparent Wind - 3 Boat goes near downwind at 5 mph after Genniker launch in 10 mph wind Subtraction shows wind is behind the boat, near 180° from the bow, speed about 5 mph. You should head up a long way to go faster. Get the wind across the beam This mode is beginners and launch/drop mode only Slide 7 Andy Howard Llandegfedd Sailing Club boat Apparent wind
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Slide 8 Andy Howard Llandegfedd Sailing Club Polar Diagrams - 2 Real life with apparent wind angles for fast boats Boats actually sail with the apparent wind and that is what you set the sails against
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Apparent Wind Diagram We cannot go upwind We can go down- wind only at wind speed Fastest point of sailing is “crosswind” Slide 9 Andy Howard Llandegfedd Sailing Club No go zone No go zone downwind
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Genniker Secret Gennikers are not a downwind sail! They don’t work upwind (flap and flog) They don’t work downwind (collapse) They only work crosswind So only use them crosswind Slide 10 Andy Howard Llandegfedd Sailing Club
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Using Apparent wind Remember the effect of speeding up is to move apparent wind forwards Re-set course to take advantage of apparent wind as your speed changes Bear off in gusts Head up in lulls Remember the effect of slowing down is to move apparent wind backwards So, sheet all sails accordingly Main is a big driver if used right It will come automatically with practice – your brain does the sums! Slide 11 Andy Howard Llandegfedd Sailing Club
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Polar diagrams Slide 12 Andy Howard Llandegfedd Sailing Club Inner lines. Slow boat at 10 mph wind Outer lines, Fast boat, 20mph with and without asymmetric Genniker Left hand side, 18’ skiff with extreme angles
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Essential tips At all points of sailing, including course changing and mark rounding, consider; Boat Trim Boat Balance Centreboard (does this apply to us?) Sail setting Course made good (especially applies to us!) The RYA Level 2 Five Essentials Slide 13 Andy Howard Llandegfedd Sailing Club
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Applied essentials Boats not upright need rudder to correct the course – it’s a brake All sails ought to be trimmed together When moving fast – sails need to be pulled in further. When planing, main needs to be over the boat – not set as per Wayfarer or Enterprise Limit turning speed to capability and trimming speed, don’t “fall off” Max power is when boat is upright, crews leaning out fully Slide 14 Andy Howard Llandegfedd Sailing Club
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Downwind speed tips Launch and recover Genniker whilst pointing nearly downwind, boat bolt upright Head up, ideally until both crew are on sitting out fully Hawk/burgee should be 90° to the boat at full speed If less than 45° to centre-line you are far too deep Play the Gennicker and the main, jib cleated Crew tells helm when pressure on Genniker changes – more and less. Head up when less On gusts bear away On lulls head up to maintain speed Slide 15 Andy Howard Llandegfedd Sailing Club
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Gybing angles Most boats it’s about 90° through the gybe (less when very windy) Angle on RS 400 is when the buoy is seen behind the mainsail when the helm is sitting out Apparent wind will then always be abeam (real wind is much further back) Slide 16 Andy Howard Llandegfedd Sailing Club
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Upwind Exercise – why? Check 5 Essentials Boats flat Sails right Course Made Good - ~45° to wind Check Tacks Clean rounding Roll if wind strength suitable Sheeting in together on the up-roll Get back upwind to start downwind work! Slide 17 Andy Howard Llandegfedd Sailing Club
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Upwind Exercise – how? Coach to gather boats by follow-my leader Two whistles – head upwind One whistle – tack Next whistle – tack, etc Video attempted of each boat – check Angle of heel Rudder central Sail setting Course made good Slide 18 Andy Howard Llandegfedd Sailing Club
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Downwind Exercise – why? Check 5 Essentials Boats flat Sails right Rudder near central – little force needed Course (Made Good) - ~45° to down-wind Check Gybes Clean rounding Roll if wind strength suitable Sheeting in together on the up-roll Maintain planing See how fast you can go! – that’s the racing line Slide 19 Andy Howard Llandegfedd Sailing Club
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Downwind Exercise – How? Coach to gather boats by follow-my leader Two whistles – head downwind One whistle – gybe Next whistle – gybe, etc Video attempted of each boat – check Angle of heel? Rudder central? Sail setting Speed and course Slide 20 Andy Howard Llandegfedd Sailing Club
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Different speeds? Up and Downwind exercises will be longer legs for the faster boats Join in when boats “collect” you upwind or down to keep connected to the group Stay together if feasible – you will learn less if totally isolated Slide 21 Andy Howard Llandegfedd Sailing Club
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Capsizing If you capsize, we will probably continue the exercise and leave you once OK Multiple Capsizes – go in and have a rest All capsized – its probably too windy! Slide 22 Andy Howard Llandegfedd Sailing Club
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Genniker Launch Communicate Bear off to Dead Run, Bolt upright Kicker off, rig tension on (400 – confirm Pole out, helm swings it then and not before) Hoist like crazy, long pulls, use legs, say when done Head up for power, both hike if at all possible Slide 23 Andy Howard Llandegfedd Sailing Club
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Genniker Recovery Communicate! Bear off to Dead Run, bolt upright, helm does all balancing with main sail Long pull, use legs, fast as possible Move around under control, don’t bang around and upset the balance Crewe kicker back on, Outhaul on Mark settings on rig and other controls Slide 24 Andy Howard Llandegfedd Sailing Club
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Streamlines Slide 25 Andy Howard Llandegfedd Sailing Club The back – leach of each sail should be parallel – including the mainsail
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Hoist to Drop life cycle Slide 26 Andy Howard Llandegfedd Sailing Club Power Zone Hoist Zone Drop Zone
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Apparent Wind 4 Slide 27 Andy Howard Llandegfedd Sailing Club Boat goes upwind at 45° from real wind (say 5 mph) Complex trig – (really!) shows wind is further to the front of boat, 30° from the bow (moved by 15°) The apparent wind speed is now 14 mph This is why its colder upwind – there is more of it. The angle is very slim between stalled and overpowered Faster boats may plane towards the wind – but control is on a knife edge wind boat Apparent wind
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Rudderless Sailing Why? – because the rudder is a brake – the less its used, the better. (how do you steer a bicycle – with no hands?) So how do we steer/go straight? Adjust the sails Adjust the heel of the boat Adjust the crew position Use sail controls What advantages? – go faster, better control, better manoeuvring Slide 28 Andy Howard Llandegfedd Sailing Club
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Bearing away / Luffing up Bearing away – windward mark Mainsail let loose, jib kept in Roll boat to windward Luffing up – leeward mark Roll boat to leeward Pull mainsail in hard Use the rudder to “follow” the boat Slide 29 Andy Howard Llandegfedd Sailing Club
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What to do with Gusts
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