NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Just getting started
From: Lu Abel
Date: 2007 Jan 19, 19:32 -0800
From: Lu Abel
Date: 2007 Jan 19, 19:32 -0800
One really great page Gary omitted: You can check your Hc calculations against the US Naval Observatory's idea of what they ought to be. Plug in a DR L/Lo and time of observation, and it gives Hc and Zn for all visible bodies! http://aa.usno.navy.mil/data/docs/celnavtable.html Lu Abel Gary J. LaPook wrote: > > Gary LaPook wrote: > > There are many web sites that have information available on navigation. > You can access Bowditch On Line free at: > > > http://www.i-DEADLINK-com/bowditch/ > > > you will soon learn that "Bowditch" (The American Practical Navigator > published by the US Navy Hydrographic Office (H.O.) as publication > number 9; H.O. number 9) is the standard reference work on this subject. > > > > You can access, for free, an online version of the Nautical Almanac at: > > http://www.tecepe.com.br/scripts/AlmanacPagesISAPI.isa > > unfortunately it doesn't include the increments pages from the N.A. > which are needed. However, if you get your hands on an old copy of the > N.A. you can use its increments tables because they do not change from > year to year. > > You can also download. for free, a program that does the celestial > computations for you which is handy when making many practice shots and > also for checking your work when doing the computations by hand: > > http://www.tecepe.com.br/nav/default.htm > > > For tables either H.O 249 or H.O. 229 or H.O. 214 are all very similar > and 249 is the most convenient but only has a precision of one minute of > arc which is an accuracy on one nautical mile which is realistic on a > small boat. If you want higher precision, especially for practice shots > while on shore, then 229 or 214 will do. 214 is out of print but I > think its arrangements of the tables is more convenient than in 229. > > BTW, does anybody know why they switched from the 214 format to the 229 > format so you cant just do a round of sight using only one page as you > could do with 214 but have to chase all over for the LHAs? > > If you want a short tabular method H.O. 208 is my preference. > > You can find many of these books on ebay. > > > > > --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to NavList@fer3.com To , send email to NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---