NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Set and drift
From: Gary LaPook
Date: 2011 Nov 9, 01:10 -0800
From: Gary LaPook
Date: 2011 Nov 9, 01:10 -0800
BTW, you can also do the computation on a standard slide rule. Line up the RWA on the sine scale with the airspeed on the D scale. Then look for the wind speed on the D scale and read out the WCA on the sine scale. If it is a tail wind add the WCA to the RWA and look at that angle on the sine scale and take out the GS on the D scale. The problem with a regular slide rule is that you might run off the end and have to reposition the slide and you don't have this problem with the MB-2A since it is a circular slide rule. Doing an example with boat speeds. Speed of the boat is 6 knots, the current speed is 2 knots and the angle between the course and the current is 40 degrees. Line up 40° on the sine scale with 6 on the D scale, look at the current speed, 2, on the D scale and take out the correction angle to keep you on course of 12° on the sine scale. If the current is from behind add the 40 and 12 and look at 52° on the sine scale and take out the speed over the bottom of 7.5 K. If the current was from ahead subtract 12 from 40 and look at 28° on the sine scale and take out the speed over the bottom of 4.4 K gl --- On Sun, 11/6/11, Gary LaPook <garylapook@pacbell.net> wrote:
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