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 5, 16:57 +0000
From: Bill Lionheart <NoReply_Lionheart@fer3.com>
To: luabel@ymail.com
Sent: Wednesday, April 5, 2017 8:00 AM
Subject: [NavList] Re: Accuracy of consumer-grade GPS/GLONASS nav.equipment?
From: Lu Abel
Date: 2017 Apr 5, 16:57 +0000
The primary purpose of WAAS is to allow aircraft land under conditions of near zero visibility. That means you want a system that will put your aircraft into the center of the runway, not 10 or 15 or 20 meters on either side. Which, in turn, means that its primary accuracy requirement is at ground level. Being off by a few dozen or even a few hundred of yards while you're at altitude is inconsequential; not so when a few feet off the ground on final approach.
From: Bill Lionheart <NoReply_Lionheart@fer3.com>
To: luabel@ymail.com
Sent: Wednesday, April 5, 2017 8:00 AM
Subject: [NavList] Re: Accuracy of consumer-grade GPS/GLONASS nav.equipment?
My understanding is SBAS/WAAS is for aircraft primarily which is why it does not work so well at sea level. Also one suspects GPS is optimized for the US and GLONASS for Russia... is that right you would think the military would optimise for where they expect to fight.