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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Unwarranted levels of precision
From: Paul Hirose
Date: 2017 Dec 20, 16:44 -0800
From: Paul Hirose
Date: 2017 Dec 20, 16:44 -0800
When the fire department in my area calls for an air ambulance, they give the coordinates of the landing spot to .001 arc minute. Sometimes the units on scene are too busy to take a GPS fix, so the dispatcher gives the copter "approximate" coordinates in degrees, minutes, and seconds to 4 decimal places. I believe they are reading that off a GIS at the dispatch center. But the biggest case of precision overkill I have ever heard was a transmission to a Los Angeles County Sheriff helicopter searching for a missing hiker. A cell phone company provided lat/lon which was relayed to the copter in decimal degree format with 14 decimal places. Then the copter read back all the digits for confirmation. The only comment was, "those are the most specific coordinates I've ever seen."
