We have been using GPS Blending for 10 or so flights without issue on Arducopter 3.5.2. During our last session flying we got a pre-arm fail of “GPS Blending Unhealthy” (I dont have a log as we dont log while disarmed - although we can turn on and try again) I had to disable the blending function (GPS_AUTO_SWITCH) back from 2 to 1 (Use Best) to fly.
What we would like to learn about initially is what are the causes that would trigger this pre-arm fail.
Now GPS 1 is “failing configuration checks” This is a copter that is identical, but never had the “blending” issue. There are 19 Sats so I’m stumped. I have 6 identical Vulcan Hexacopters used for agriculture.