NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Accuracy of consumer-grade GPS/GLONASS nav.equipment?
From: Lu Abel
Date: 2017 Apr 6, 16:47 +0000
From: Bill Lionheart <NoReply_Lionheart@fer3.com>
To: luabel@ymail.com
Sent: Thursday, April 6, 2017 8:20 AM
Subject: [NavList] Re: Accuracy of consumer-grade GPS/GLONASS nav.equipment?
From: Lu Abel
Date: 2017 Apr 6, 16:47 +0000
This has been a point I've tried to make many times -- especially when people question whether an Astra (or even a Davis Mark 25) is "good enough" -- noting that there's often a significant difference between an instrument's absolute accuracy and the accuracy that can be practically achieved on the heaving deck of a vessel at sea. I have taken shots from the deck of my 36 ft sailboat and even with the steadying effect of my sails I'm lucky to get an LOP within five miles of my GPS position.
From: Bill Lionheart <NoReply_Lionheart@fer3.com>
To: luabel@ymail.com
Sent: Thursday, April 6, 2017 8:20 AM
Subject: [NavList] Re: Accuracy of consumer-grade GPS/GLONASS nav.equipment?
Come to think of it what do people do for Celnav on a heaving deck I admit I have only tried it in fairly calm conditions sitting eg on the coachroof - I suppose that is not very realistic practice! Does anyone stand up with one arm crocked around the mast to get a better view of the horizon? Bill -- Professor of Applied Mathematics http://www.maths.manchester.ac.uk/bl
