NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: GPS backup/emergency navigation
From: Denis Gutar
Date: 1998 Nov 26, 21:04 EST
From: Denis Gutar
Date: 1998 Nov 26, 21:04 EST
Would anyone please scan these 3 or 4 pages from Bowditch for us the arnchair navigators? -----Original Message----- From: Rick Emerson <rick@XXX.XXX> To: navigation@XXX.XXX> Cc: Mark Anderson <andermar@XXX.XXX> Date: November 25, 1998 10:57 AM Subject: [Nml] Re: GPS backup/emergency navigation >A friend wrote the following comments in response to a discussion >about the need for sight reductions with the Nautical Almanac and >sight reduction tables of some sort (e.g., HO 249) versus doing the >reductions by solving the navigation triangle "by hand". > >[...] > > No you don't, i.e. need an almanac or HO 249. Well, you need an almanac, > > but the perenial one in Bowditch that's about 3 or 4 pages long will > > suffice for the sun and stars. It's based on the fact that the almanac > > nearly repeats every 4 yrs. and a fudge factor is added. A few basic trig > > formulas and you don't need 249 =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-= =-= TO UNSUBSCRIBE, send this message to majordomo@XXX.XXX: =-= =-= navigation =-= =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-=