I've got a NEO-6M on a F-450 quad. During stable mode flight, I see no significant (unexpected) changes in the reported GPS position. Telemetry shows the flight. The little dot/line shows up in mission planner just where it should
Now, turn on a mission, and very frequently, I'll get the APM seeming want to flight off in an 'odd direction'. this isn't compass related. The compass bearings are just fine. The telemetry shows that the GPS reported position has changed massively (say 600 feet away), and then after I kick it back to stable mode, a few seconds later, the reported GPS position returns to what it should be.
Is there any way to verify if I've put the appropriate ublox configuration onto the GPS? (say the one that should block out large spontaneous changes in position because it's supposed to be slow moving?)
I've moved the GPS away from the F450 arm, and mounted in on a nylon standoff about 25 mm from the deck, close to APM housing. I've seen pictures of others with gps mounted on or near their APM housing, which should suggest that there's not large interference issue.
I'm open to verifyable suggestions.
FYI, this is from a GPS that had play view to the sky and appropriate power for 10-15 minutes before the flight started. This isn't a 'just turned on the GPS' problem.