This will not be used in the calculation of leeway only the real time heel measured by the heel sensor is used as a value in the calculation of leeway. Heel Polar: Used to generate / display polar / target heel as a value that should not be exceeded in heavier breezes or possibly aspired to in very light stuff. "Commodity level laptop" is a term I first encountered here on this forum (Thanks JB) and it really is germane to utilizing Expedition in the ocean racing circumstance. This can be obviated by using two PCs with one dedicated to the performance monitoring and a second dedicated to routing and Race Schedules. Note: It follows from the above that it is often necessary to switch scaling percentages in the Nav Polar during a point-to-point event when using the Nav Polar for both routing and predicting time to laylines. Perf Polar: This should be the MH polar to be used to monitor boat performance in real time. If no MH polar is available as a Perf Polar then use the 10M polar but scale it up to MH wind velocities that you will encounter, again using the Help file to obtain the scaling method / formula. If no 10M polar is available as the Nav Polar for routing then use the MH polar as the Nav Polar but scale the grib winds up to MH velocities, again using the method / formula set forth in the Help file. This should be the 10M polar when routing as you will be using 10M winds from the grib file. If no MH polar is available as the Nav Polar for buoy racing then use the 10M polar as the Nav Polar but scale the polar up to the MH velocities that you will encounter, using the method / formula set forth in the Help file. Nav Polar: This should be the MH polar when buoy racing as it is used to calculate laylines. I will try to address some of your questions and I hope that my explanations can be supplemented by others and corrected if my understandings appear flawed. Practice, the help file, the webinars, Will Oxley's book, and this forum have all contributed significantly to whatever limited proficiency I have acquired. I bought Expedition in 2012 and I am still on a steep learning curve. Heel and leeway again seem obvious in intent, yet not clear if they modulate other calculations eg leeway affects lay lines, heel angle ? I'd guess that these numbers should reflect less than a minute of acceleration, and so at higher TWS might approach Perf, but at low would be significantly less, especially if your boat is higher displacement/sail area and your starting box is constrained. Start seems eponymous, the data should reflect performance during reaching and maneuver, rather than asymptotic optimized speed, combined with the acceleration, Rate of Turn and braking parameters. I'm not clear what the difference in Perf vs Nav usage and thus what the specific data should be. Nav seems to be the basic set that predict sailing speed. The polar5-9 I take to be for future use, or what if display. There was also a "Leeway" in the Farr 40"set, which with a CCA centerboard yawl, I suspect I need, but don't as yet have data for. Those curves were not monotonic in mid speeds as TWA changed, which makes sense. "Heel": from another post I took the hint to review the supplied Farr 40 heel, and realized I could extract the "phi" term from US sailing and enter for TWS x TWA grid to tell EXP my predicted heel. As my Asym and Genoa polars are near identical I'll hold off for some calibration before editing here. In the North U buoy course Peter suggested deprecating the downwind numbers to reflect no-spinnaker pre start, which makes a lot of sense. Thanks to those who pointed out the omission. "Start": I originally missed loading here, and had some odd behavior in simulated starts without them. "Perf": I also loaded them here, but didn't scale or edit as yet
"Nav": I loaded the US Sailing VPP, masthead corrected polars for my boat here. To that end I am stating my limited understanding and hoping that it will be improved by those with further progress along the path pointing out my errors. It became clear the other day while taking the North U buoy course that I didn't understand the many polars that are available, where and when they are used and why. My style of learning software has generally been to scan the menus and dive in, referencing user guide,manual or in extreme cases tutorials as needed, while teaching myself the tool.
Having recently started with Exp, I'm on a steep learning curve.