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don1reed · 02-09-11, 10:01 AM

Full disclosure, Mike. I mistakenly referred to Gnomonic chart as Conic in our last email.

An here is the reason DR doesn't work in the games:

from HO Pub No.9 The American Practical Navigator a.k.a. Bowditch, 1995

A Gnomonic chart provides the navigator a GREAT CIRCLE course. When laid out on a Mercator chart it becomes a curved course made up of many, small, Rhumb line courses. It provides the navigator the shortest distance course between two points...in case some of you have been wondering why you've been running out of fuel in operation Paukenschlag [sic] when crossing the Atlantic.

Soooo....every time you construct a long straight line course (>600 nm) on the F5 chart (which is made to look like a Mercator, but really isn't) you are going many extra miles out of your way to get between the two locations.
Proof: That straight line course on a Mercator chart, is now a curved course on a Gnomonic chart. (they are inversely proportional).

Simply put, the F5 chart is not a Mercator Projection chart and it makes DR navigation very difficult.
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02-09-11, 10:01 AM	#183
don1reed Ace of the Deep Join Date: Dec 2004 Location: Valhalla: Silent Generation Posts: 1,149 Downloads: 910 Uploads: 0	Full disclosure, Mike. I mistakenly referred to Gnomonic chart as Conic in our last email. An here is the reason DR doesn't work in the games: from HO Pub No.9 The American Practical Navigator a.k.a. Bowditch, 1995 A Gnomonic chart provides the navigator a GREAT CIRCLE course. When laid out on a Mercator chart it becomes a curved course made up of many, small, Rhumb line courses. It provides the navigator the shortest distance course between two points...in case some of you have been wondering why you've been running out of fuel in operation Paukenschlag [sic] when crossing the Atlantic. Soooo....every time you construct a long straight line course (>600 nm) on the F5 chart (which is made to look like a Mercator, but really isn't) you are going many extra miles out of your way to get between the two locations. Proof: That straight line course on a Mercator chart, is now a curved course on a Gnomonic chart. (they are inversely proportional). Simply put, the F5 chart is not a Mercator Projection chart and it makes DR navigation very difficult. Uploaded with ImageShack.us __________________ [SIGPIC][/SIGPIC] During times of universal deceit, telling the truth becomes a revolutionary act. ~ George Orwell Last edited by don1reed; 02-09-11 at 10:15 AM.