My geometry for calculating leeward layline: If my ideal heading for the current conditions is 230* and TWD is 270*, that means my stern has to swing 40* to become dead downwind, and another 40* to get to the reciprocal course after the jibe. In a perfect scenario, this means an 80* swing. So, when the windward mark is at a bearing of 80* I'm on the leeward layline. Bearing to the mark can thus be calculated as 2 x (180-TWA).
Bob > On 10/08/2021 11:15 AM Bob Mann <sailrm...@comcast.net> wrote: > > > I still need to review the geometry, but I believe that when the bearing > to the mark is equal to 180-TWA, one has reached the downwind layline. I > also found that when the masthead is pointing at the mark, that also > indicates the layline has been reached. > > Bob > > > > On 10/06/2021 11:17 AM Jeff Nelson via CnC-List > <cnc-list@cnc-list.com> wrote: > > > > > > Hmmm...Interesting question. > > > > So, Ed's answer was pretty good, I'll add a few thoughts here: > > > > AW isn't an ideal guide, True wind is what is needed so that you > > can keep the angle to true wind to be constant on > > either Gybe, assuming you know what the best angle is. > > If you can find polar's for your boat, they will give you an idea > > of ideal. > > As Ed mentioned, VMG is your friend in determining what the best > > angle is (especially if no polars are available). > > You can experiment in different wind speeds to find a reasonably > > good angle for windspeed and VMG. > > > > Here's a good article to get you thinking: > > http://www.oceansail.co.uk/Articles/VMGArticle.php > > > > Hope this helps. > > Jeff Nelson > > Muir Caileag > > C&C 30 549 > > Armdale Yacht Club > > > > On 2021-10-06 12:02 p.m., Bob Mann via CnC-List wrote: > > > > > > > I'm fairly new to flying a spinnaker. I did > > it last weekend in a race and I believe I overstood the mark as we were > > sailing 110 AW before the gybe and 85 AW heading directly to the mark. > > > > > > How does one determine when to gybe? > > > > > > Bob > > > > > > > > > Thanks to all of the subscribers that contributed to the list > > > to help with the costs involved. If you want to show your support to the > > > list - use PayPal to send contribution -- > > > https://www.paypal.me/stumurray Thanks - Stu > > > > > > > > > > > > https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient > > Virus-free. www.avast.com > > https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient > > Thanks to all of the subscribers that contributed to the list to > > help with the costs involved. If you want to show your support to the list > > - use PayPal to send contribution -- https://www.paypal.me/stumurray Thanks > > - Stu > > > > >
Thanks to all of the subscribers that contributed to the list to help with the costs involved. If you want to show your support to the list - use PayPal to send contribution -- https://www.paypal.me/stumurray Thanks - Stu
