Yesterday after a rather perfect mission flight, my current build did a very hard landing which broke a few things. It was in normal landing mode and suddenly came down very fast. I have done my own log analysis and my working theory so far is that a GPS glitch led the EKF to failsafe and invoke an emergency landing. LAND_SPEED_HIGH was set to 0 and WPNAV_SPEED_DN to 150 which is somewhat consistent with the “crash” speed I saw. I would be grateful for a second opinion on that analysis.
The other question is how do I avoid those kind of issues in the future. I’m using an uBlox M8N which gives pretty good accuracy. Sky was clear and I was flying in an open area. I see no possible reason for a GPS glitch. Is it possible to “turn down the sensitivity” of the glitch detection?