NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: leeway
From: Greg R_
Date: 2006 Jul 7, 00:45 -0500
From: Greg R_
Date: 2006 Jul 7, 00:45 -0500
Lu wrote: > Traditionally in ocean navigation, DR is based solely on speed, time, > and course steered. > If one is sailing with a known leeway or set and drift of current, one > adds that information to the DR to arrive at an estimated position > (EP). Usually a dotted line is drawn between DR and its corresponding > EP and the information used to determine the EP is labeled on the line > ("leeway est 4 degrees" or "current, set 295, drift 0.5 kts") Gotcha... I'd seen both terms batted around in the navigation literature, but never really bothered to check on the actual "formal" definition for each term - thanks for clarifying that for me. :-) -- GregR --- Lu Abelwrote: > > Traditionally in ocean navigation, DR is based solely on speed, time, > > and course steered. > > If one is sailing with a known leeway or set and drift of current, > one > adds that information to the DR to arrive at an estimated position > (EP). > Usually a dotted line is drawn between DR and its corresponding EP > and > the information used to determine the EP is labeled on the line > ("leeway > est 4 degrees" or "current, set 295, drift 0.5 kts") > > Lu Abel > > Greg R. wrote: > > Clive wrote: > > > > > >>Does anyone know of a really good way of checking leeway? > > > > > > Along those lines, is it common in ocean navigation to try to > estimate > > set and drift (and I'd guess true wind and leeway, too) and factor > that > > into the DR position estimate? > > > > I know that in aviation navigation we have to calculate the heading > for > > a given leg based on wind correction angle, but I've never seen any > > reference to a similar allowance being made for that by our > ocean-going > > counterparts. > > > > -- > > GregR > > > > > > > >>Hi All; > >> > >>Back online again after a long while! > >> > >>Franks recent mail about using floating styrofoam reminds me that I > >>suggested using this as a means of checking leeway (by back bearing > >>on a floating paper plate) some while ago but nobody took this up I > >>will try and revive it.. > >>Does anyone know of a really good way of checking leeway? > >> > >>Clive. > >> > >> > > > > > > > > > > > > > --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to NavList@fer3.com To , send email to NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---