NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Traditional navigation by slide rule
From: Gary LaPook
Date: 2016 Jan 7, 18:59 +0000
From: John Brown <NoReply_JohnBrown@fer3.com>
To: garylapook@pacbell.net
Sent: Thursday, January 7, 2016 7:04 AM
Subject: [NavList] Re: Traditional navigation by slide rule
Attached File:
(Blundell_Harling_SuperDuplex.jpg: Open and save)
From: Gary LaPook
Date: 2016 Jan 7, 18:59 +0000
The most useful scale found on yours and not on the K&Es is the second tan scale starting at 45 degrees. Without this second tan scale you end up needed some tricks when dealing with angles greater than 45 on the K&E. My Pickett N 3-T and my Pickett N 3-ES and even the cheap Stirling have the second tan scale. (Actually, the K&E does have a second tan scale but it is inverted so requires different procedures when using it, I don't understand why K&E did it this way.)
gl
From: John Brown <NoReply_JohnBrown@fer3.com>
To: garylapook@pacbell.net
Sent: Thursday, January 7, 2016 7:04 AM
Subject: [NavList] Re: Traditional navigation by slide rule
Attached is a pic of my Blundell Harling Super Duplex Academy 504 - sea navigation model, as endorsed by Podmore. Unusually for a UK made slide rule the trig functions are on the slide. They are divided sexagesimally, which I find slightly inconvenient with my no longer perfect eyesight.
John
Attached File:
(Blundell_Harling_SuperDuplex.jpg: Open and save)
