NavList:

Doug,

I like your list 1 through 5.

You added:
"For Longitude: time sights. This will be when far from land.
Near landfall, traditional LOP's for a fix. "

Some of the posts I've read in this topic seem to imply that folks believe that the time sight is still in some way inferior to a "traditional" LOP. It's not. It's equivalent to a single point on an LOP that is every bit as good as one generated with an intercept method. In fact, if you follow Sumner and simply work each time sight twice with somewhat different latitudes, the line of position that you get by running a line through the two lat/lon's is every bit as good as an LOP generated by any more modern method, just so long as you're using tables that have similar mathematical accuracy to a "modern" method.

By the way, there's one BIG advantage of a Sumner line of position over an intercept method LOP that may not have been mentioned yet (or emphasized loudly enough). You can plot Sumner lines on ANY graph paper. You don't need the "conformal" projection of a plotting chart; you don't have to worry about the changing scale for longitude that preserves angular relationships since you never calculate or plot any azimuths. Of course if you want to use a single LOP for bearing on land or similar then you would need to use some sort of conformal plotting chart, but that's a secondary application of the method.

-FER

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