Using Target Boat Speed

you can stop reading if you have satisfied your question the following is just more boring details of where Target Boat Speed comes from and how to use themP89 TARfff Y Y llfff Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Yffff333fff333 Offff Y Y Y Yffff333fff333 Slffff Y Y Y Yffff333fff333 SOffff Y fff Y Y Y Yfff333fff333 ffff Y Y Y Yffff333fff333 J3 ffff Y Y Y Yffff333fff333 J385 ffff Y Y O l23ll 6 nO333M M M 333M M M M 33333333ffJ3 333333M M M 6 n G 333333M M M 1 1O M 33333O3333M M 33331l13O M M 333O23333M M M 333 3333M M M 3O M 332 M 333 l33333M M M M 1 M M 33 6 nG 13333M M G 6 nM M M 333 6 n 333333M 333M M M 336 n 33333M M 3333M M M 333J M 33333M M 3333M M 333 23M G 2333333M 33333M M M M 3333M M M M 3333333 6 n l333333M M G 3M 3333M M M M 33333 3333 M 33333333M M l333 M 2l2333333M M E 133 G O33333333M M M M G 33 E 23333333333333 33333333O3333 333E M l3332lOM l23M 33M M l2333M 3ll333M O33O3333M 333333333M 3333333336 n M 333331O33333 E M M 333Sff3333 GJ M 333ff3333 6 nM 333O3fff333 M 32l333333333G M 1O33333333OJ M J 3333333M L SfvKL r44114r 1rs4R4RRR4r L R1LLL11 L41 K1 8LRL LV 2OjJ22jJ81prrV Vr prr1 r jJ2lCE11 18 L Sfv ls1uprr1v 1 r 4 SfvR 841 Vu1u1 4 rD5u22222 u4 jJCELCE 1l8 L L4lL R L RR K Sfv1 s VMG is defined as velocity made good against the direction of the wind VMG is that portion of the boats velocity vector which represents the progress of the boat against the wind and is quantified by the expression VMG Bs x COSTWA where TWA is the the angle between the direction of the wind and the direction of the boat Fig 4 ThusTrue Wind Angle TWSBoat Speed Bs024160 kts4524160 kts9024160 kts13524160 kts18024160 ktsFigure 4 VMGVMC VMC is defined as velocity made good against the course to the mark not the direction of the wind VMC is commonly confused with VMG Generally a GPS or LORAN will give VMC as the speed made good towards a mark or waypoint over the bottom not through the water this is sometimes labeled as VMG by the GPs or LORAN Only when the bearing to the mark and the bearing of the True Wind are the same will VMC be equal to VMG VMC Bs x COsAm where Am is the angle between the direction of the mark or waypoint and the direction of the boat Fig 5Figure 5 VMCTrue Wind Speed True Wind Angle True Wind Speed TWS and True Wind Angle TWA are the speed of the wind relative to the water and the angle of the wind relative to the bow of the boat respectively Apparent Wind Speed AWS and Apparent Wind Angle AWA are the vector sums of the True Wind Speed and angel and boat speed This is the wind you feel as the boat moves through the water and the wind the sails see Fig 6Figure 6 TWS TWA AWS AWAtheoretical goalsin theory the jib Telltales are for trimmers only and the helmsman watches the Boat SpeedFigure 7 Target Boat Speed You know that if you sail too high for too long a time period performance will decrease and if you sail too low performance will decrease Target Speed therefor is the value which you should always try to maintain to stay at maximum performance The important concept is to identify the target speed for a True Wind Speed and then use the target speed to monitor the performance of the boat and sailing techniques of the crew Apparent Wind Angel or True Wind Angle and VMG functions do not have the inherent stability to verify your performance upwind or downwind especially over the entire period of the leg of the course Target Speed is the upper and lower limit of speeds for sailing upwind and downwind to maximize performance The telltales will not tell you the whole story over these speed changes If you are too fast head up When you are too fast you should head up but the telltales will indicate that you are too high In these instances disregard the telltales until boat speed approaches target then bear off to hit target at the proper wind angel with the tell tales flying Likewise if you are too slow bear off to accelerate to Target Boat SpeedThe telltales will tell you that you are sailing too low again the helmsman should disregard the telltales and the trimmer should adjust the sails until boat Speed approaches target speed and then head up so that you hit target speed at the proper wind angle and adjust the sails accordingly Using the apparent wind angle function or Windex to steer by especially at night is slow The technique emphasizes the coordination required between the trimmer and helmsman Both the jobs of the helmsman and trimmer should be regulated by the Target Speed Boat Speed fast head upIf you are too fast1 Trimmer should trim slightly as you head up 2 As excess speed starts to bleed off Trimmer should ease to allow you to them bear off and maintain speed again 3 Helmsman should call out above target trim slightly Coming up trim with me Boat speed slowing east to proper trim at target Or something to that effect 4 Helmsman starts to come down to reestablish target speed This is a constant loop with constant positive interaction between Helmsman and Trimmer Tactician can then use excess speed to his advantage tactically against other boats A good example of this use is in sailing through changing sea states Assume that you are sailing in 23 chop at target speed and the boat enters a smooth condition with 1 chop Boat Speed starts to accelerate as the boat hits smooth water Use this excess speed to sail higher and gain distance to weather maximizing performanceToo slow bear offIf you are too slow1 Trimmer should ease sails to allow you to bear off and accelerate 2 Helmsman should call out below target ease sheets bearing off 3 As the boat speed builds towards Target Trimmer starts to trim Helmsman slowly starts bringing the boat back to close hauled 4 When Boat Speed reaches upwind target Helmsman call out Boat Speed at target full upwind trim and Helmsman settles in at target Speed upwind Again this is terrifically positive and productive interaction between the crew for maintaining maximum performance upwind As the previous example this coordination of Helmsman Trimmer and Target Boat Speed allows you to maintain maximum performance when you enter a rough patch of water sailing through a current rip or backwash near a shore As the boat enters the rough water and Boat Speed slows you reestablish target speed quickly allowing you to preserve your maximum performance for Sea speed can compensate for overall sea conditions1 In smooth water the boat is able to sail to Target speed while pointing high The average sailing angle is closer to the wind and target speed is maintained The same rules apply during shorter changes in sea state too fast head up too slow bear off2 In rough seas the Target Speed will remain the same but the average wind angle will be wider and you will have to sail lower because of the sea conditions However the theory of target speed s hold true too fast head up too slow bear offIm not competitive when I sail to the Targets The Targets posted here on the website are for the individual boats as noted For instance the Targets for Deviation are for using a 143 headsail with a 14 OD size girth Spinnaker Thus if you have tried the Targets and have failed to be satisfied then you can establish your own through trial and error which is optimized for you own boat set up and style of sailingThe best targets you can get are developed thought experience In other words how does your speed and point compare with other boats Your own testing and date recording before and during races is extremely valuable data You can construct your own set of polars or update existing polars with footnotes of sail selection lead position halyard tension and sea conditions TWS Upwind Sail Downwind 3 24 143 21 06 oz 5 40 143 37 06 oz 8 56 143 55 06 oz 10 59 143 60 06 oz 12 60 143 64 06 oz 13 61 105 66 06 oz 15 62 105 70 06 oz 18 63 105 78 06 oz 20 63 105 82 06 oz 23 63 105 88 06 oz 25 64 105 93 06 oz 30 65 90 107 06 oz Sample Duct Tape Strips re Deviation 2002 Three pieces of duct tape in the cockpit can be the most guide on the boat With True Wind Speed on the first piece of tape Target Boat Speed and Headsail for upwind and Target Speed for downwind sailing Use the true wind function to reference the target speed Continuously checking boat speed against target speed will maximize your performance As True wind changes check your new target speed and respond to maintain maximum 1 Helmsman checks True Wind Speed 2 Helmsman identifies target speed for that True Wind Speed 3 Helmsman checks boat speed in relation to target speed 4 If boat speed is slow Helmsman communicates with the Trimmer to ease the sails bears off accelerates and retrimms 5 Helmsman then rechecks True Wind Speed and so on 1 Ez B7 77005Oo009BNjz ccVMG VMG is defined as velocity made good against the direction of the wind VMG is that portion of the boats velocity vector which represents the progress of the boat against the wind and is quantified by the expression VMG Bs x COSTWA where TWA is the the angle between the direction of the wind and the direction of the boat Fig 4 Thus True Wind Angle TWSBoat Speed BsVMG024160 ktsBs x 100060 kts4524160 ktsBs x 070742 kts9024160 ktsBs x 000000 kts13524160 ktsBs x 070742 kts18024160 ktsBs x 100060 kts Figure 4 VMG PGZp3Om5HXf 1F6bYALXid 2DV24CQcuNi Fp1GYizBTh 1Lv87Ufs2IbnK VMG is defined as velocity made good against the direction of the wind VMG is that portion of the boats velocity vector which represents the progress of the boat against the wind and is quantified by the expression VMG Bs x COSTWA where TWA is the the angle between the direction of the wind and the direction of the boat Fig 4 Thus True Wind Angle TWSBoat Speed BsVMG024160 ktsBs x 100060 kts4524160 ktsBs x 070742 kts9024160 ktsBs x 000000 kts13524160 ktsBs x 070742 kts18024160 ktsBs x 100060 kts Figure 4 VMG VMG VMG is defined as velocity made good against the direction of the wind VMG is that portion of the boats velocity vector which represents the progress of the boat against the wind and is quantified by the expression VMG Bs x COSTWA where TWA is the the angle between the direction of the wind and the direction of the boat Fig 4 Thus True Wind Angle TWSBoat Speed BsVMG024160 ktsBs x 100060 kts4524160 ktsBs x 070742 kts9024160 ktsBs x 000000 kts13524160 ktsBs x 070742 kts18024160 ktsBs x 100060 kts Figure 4 VMG PGZp3Om5HXf 1F6bYALXid 2DV24CQcuNi Fp1GYizBTh 1Lv87Ufs2IbnK aw7Fs8OYkzMZlz