Next message: Dan Hogan: "Re: Silicon Sea: Leg 88"
Well, a dozen years and the rust has removed all of the paint. Here
are my answers to the first part, followed by questions for the
experts. I used a calculator with trig functions for the
calculations and home-made sheets for the graphical solution (after
locating my Speedbow, C-Thru ruler, and a metric scale).
1) L2 = 39d 39.0'N Lo2 = 154d 43.0'W via Mid Latitude Sailings
L2 = 39d 39.0'N Lo2 = 154d 42.1'W via Mercator Sailings
L2 = 39d 38.5'N Lo2 = 154d 43.9'W via three plotting sheets
2) 0830:20 ZT 10SEP2002 (1830:20 UT 10SEP2002 +10). Intermediate DRs
were plotted every four hours starting 0400 UT 09SEP2002, since we
are in the open sea.
Questions:
1. Are there rules-of-thumb in terms of distance limits for which I
decide to use Plane, Mid Latitude, or Mercator Sailings?
2. Plotting sheet dL = 0.5 Nm to calculated L2, which shows my
current ineptitude in plotting (used 10 sheets of paper to get three
"good" plots). How close to calculated Lo2 can I reasonably expect
to arrive with a correct plot? Note that I cheated and used dL = 2d
20' for the middle plotting sheet.
