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US Sailing
US Sailing has polars for a number of boats, but you may be disappointed with the few number of Hunters available. At one time they had a list of boats available, but I wasn't able to find it to check the 240. Also the cost is just a tad high... Steve
US Sailing has polars for a number of boats, but you may be disappointed with the few number of Hunters available. At one time they had a list of boats available, but I wasn't able to find it to check the 240. Also the cost is just a tad high... Steve
Not there
Hunter only had Polars done for the 35.5. This is something Hunter would have needed to do and last time I checked the 35.5 was the only boat. They did this for the Liberty Cup boats back in the late 80's early 90's. They used the 35.5 for some match racing and these boats are still out ther some where but they needed the Polars for the Match Racing. Some footage of it is on the Hunter Video. CLiff H 28.5 "Red Dog"
Hunter only had Polars done for the 35.5. This is something Hunter would have needed to do and last time I checked the 35.5 was the only boat. They did this for the Liberty Cup boats back in the late 80's early 90's. They used the 35.5 for some match racing and these boats are still out ther some where but they needed the Polars for the Match Racing. Some footage of it is on the Hunter Video. CLiff H 28.5 "Red Dog"
Hey Cliff
I've been trying to get my hands on polars for my 35.5 since I bought her with no luck. The ones that US Sailing had were for a modified boat with a custom mast. If you have any idea where I can get my hands on those polars for the Liberty Cup boats I would appreciate it. My boat is set up a lot like that. By the way I have that video of the match racing in Bermuda.
I've been trying to get my hands on polars for my 35.5 since I bought her with no luck. The ones that US Sailing had were for a modified boat with a custom mast. If you have any idea where I can get my hands on those polars for the Liberty Cup boats I would appreciate it. My boat is set up a lot like that. By the way I have that video of the match racing in Bermuda.
Hey Alan
I remember talking to US Sailing trying to get Polars for my 28.5 and they told me they only had info on the 35.5. I assumed it was becasue of the Liberty Cup Regatta. Getting Polars is something the Boat manufacter would need to do at time of production. Or it could be done for private use but at a fairly good cost. In the Hunter video they show a short segment of the Liberty Cup. Cliff
I remember talking to US Sailing trying to get Polars for my 28.5 and they told me they only had info on the 35.5. I assumed it was becasue of the Liberty Cup Regatta. Getting Polars is something the Boat manufacter would need to do at time of production. Or it could be done for private use but at a fairly good cost. In the Hunter video they show a short segment of the Liberty Cup. Cliff
What are Polar Diagrams??
Can someone explain what Polar Diagrams are and what they do? Are they useful for non-racers? Thanks Peter Milne S/V Blue Heron
Can someone explain what Polar Diagrams are and what they do? Are they useful for non-racers? Thanks Peter Milne S/V Blue Heron
What are racers??
The "racing" guys are sailors that want to make their boats perform to their potential. The science that is sailing is the same for cruisers and racers. Racing sailors have a need to learn all there is to know about making the boat perform. Cruisers are basically not interested in this. Polars are diagrams drawn to show how any given sail will perform in any given wind speed and direction for a specific hull. Having these (polars)diagrams makes it easy to choose the best sail and sailing angle for optimum up wind or down wind VMG.
The "racing" guys are sailors that want to make their boats perform to their potential. The science that is sailing is the same for cruisers and racers. Racing sailors have a need to learn all there is to know about making the boat perform. Cruisers are basically not interested in this. Polars are diagrams drawn to show how any given sail will perform in any given wind speed and direction for a specific hull. Having these (polars)diagrams makes it easy to choose the best sail and sailing angle for optimum up wind or down wind VMG.
Make your own...
Polars are simply a graphic presentation of a table of performance on a particular boat. They can be built by tracking wind conditions and boat performance in a spreadsheet or chart, and then plotting the results. FYI, if you have Raymarine's RayTech Navigator charting software, they have just reciently opened up the Sail Racer program as a standard feature in version 4.1. This builds the polars for your boat as the data is entered. You have to ask them for the key, but I suspect that version 5.0 is due to be released very shortly, and will have the feature as well. Steve
Polars are simply a graphic presentation of a table of performance on a particular boat. They can be built by tracking wind conditions and boat performance in a spreadsheet or chart, and then plotting the results. FYI, if you have Raymarine's RayTech Navigator charting software, they have just reciently opened up the Sail Racer program as a standard feature in version 4.1. This builds the polars for your boat as the data is entered. You have to ask them for the key, but I suspect that version 5.0 is due to be released very shortly, and will have the feature as well. Steve
True, I've been doing that...
....but it is very time consuming. Frankly I'd rather be sailing, as that bumper sticker says. Anyway it sounds like Raymarine is on the right track putting that software together. I would like to see it in action.
....but it is very time consuming. Frankly I'd rather be sailing, as that bumper sticker says. Anyway it sounds like Raymarine is on the right track putting that software together. I would like to see it in action.
Polar Diagrams are usually generated...
...by running a Velocity Prediction Program (VPP). The VPP has algorithms that incorporate hydrodynamic and aerodynamic mathematical models of a sailboat based on the physical input parameters of a particular sailboat. The software program generates results that predict how fast a particular sailboat will perform in varies points of sail. The predicted speed is the Velocity Made Good (VMG) or target speed of the sailboat, it's the theoretical best speed the sailboat can make based on the wind angle and speed. For example, base on a hypothetical polar diagram a sailboat sailing with a wind speed of 10 knots; the best angle to sail upwind is 40 degrees which will give you a VMG or target speed of 6 knots. If that same sailboat fell off to an angle of 35 degrees the boat speed would be 5.6 knots. The Polar diagram determines the optimum sailing VMG or target speed to get the boat into the groove as quickly as possible while racing. If you generate polar diagrams using chart plotting electronics, the polar diagrams are polar diagrams of how well you and your crew can sail your sailboat, and not necessarily the VMG of your sailboat, unless the helmsman and sail trimmers are world class sailors who can react like America's Cup sailors. Polar diagrams are the theoretical benchmarks or goals based on algorithms used in the VPP in which you and your crew shoot for while sailing to get as much speed out of your sailboat while racing. The US Sailing organization generated the first "VPP", which was written at MIT. As stated in a previous post you can buy the results of the VPP computer program from US Sailing, which will be the polar diagram for your sailboat. I don't think that the VPP has the algorithm for a "Water Ballast" sailboat such as the Hunter 240 or 260. The US Sailing organization also has a "Pay-As-You-Play" web site that has a "Watered Down" VPP that will generate a polar diagram based on a very limited amount of input parameters. You have to submit a credit card and I think it costs you $5 to run the calculation and get a result. I haven't tried it, so I don't know whether it's worth it. You can also surf the web for companies with VPPs that will generate a polar diagram for your sailboat or you can buy a VPP software package. The cheapest VPP sells for $50. Unless you are a diehard racer trying to squeeze a tenth of a knot out of your boat, a polar diagram isn't worth it. If you can't make target speed or VMG, then its either the crew can't trim as fast or the helmsman is slow to respond or the bottom is foul or the sails are old or the VPP algorithm doesn't match the physical parameters of your sailboat. If you exceed target speed or VMG, then its either you should be a captain for the America's Cup or your instruments are out of calibration or the VPP algorithm is poor. Fair Winds, Clyde
...by running a Velocity Prediction Program (VPP). The VPP has algorithms that incorporate hydrodynamic and aerodynamic mathematical models of a sailboat based on the physical input parameters of a particular sailboat. The software program generates results that predict how fast a particular sailboat will perform in varies points of sail. The predicted speed is the Velocity Made Good (VMG) or target speed of the sailboat, it's the theoretical best speed the sailboat can make based on the wind angle and speed. For example, base on a hypothetical polar diagram a sailboat sailing with a wind speed of 10 knots; the best angle to sail upwind is 40 degrees which will give you a VMG or target speed of 6 knots. If that same sailboat fell off to an angle of 35 degrees the boat speed would be 5.6 knots. The Polar diagram determines the optimum sailing VMG or target speed to get the boat into the groove as quickly as possible while racing. If you generate polar diagrams using chart plotting electronics, the polar diagrams are polar diagrams of how well you and your crew can sail your sailboat, and not necessarily the VMG of your sailboat, unless the helmsman and sail trimmers are world class sailors who can react like America's Cup sailors. Polar diagrams are the theoretical benchmarks or goals based on algorithms used in the VPP in which you and your crew shoot for while sailing to get as much speed out of your sailboat while racing. The US Sailing organization generated the first "VPP", which was written at MIT. As stated in a previous post you can buy the results of the VPP computer program from US Sailing, which will be the polar diagram for your sailboat. I don't think that the VPP has the algorithm for a "Water Ballast" sailboat such as the Hunter 240 or 260. The US Sailing organization also has a "Pay-As-You-Play" web site that has a "Watered Down" VPP that will generate a polar diagram based on a very limited amount of input parameters. You have to submit a credit card and I think it costs you $5 to run the calculation and get a result. I haven't tried it, so I don't know whether it's worth it. You can also surf the web for companies with VPPs that will generate a polar diagram for your sailboat or you can buy a VPP software package. The cheapest VPP sells for $50. Unless you are a diehard racer trying to squeeze a tenth of a knot out of your boat, a polar diagram isn't worth it. If you can't make target speed or VMG, then its either the crew can't trim as fast or the helmsman is slow to respond or the bottom is foul or the sails are old or the VPP algorithm doesn't match the physical parameters of your sailboat. If you exceed target speed or VMG, then its either you should be a captain for the America's Cup or your instruments are out of calibration or the VPP algorithm is poor. Fair Winds, Clyde
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