Precision landing saw its target: the first lock failed, or succeeded

What ArduPilot says:

• PrecLand: Init Complete
• PrecLand: Init Failed

Precision landing follows a beacon or marker on the ground with its own small estimator. When the target first comes into view the estimator needs 2 s of readings, with no gap longer than 0.5 s, before its output is used. “Init Complete” says it got them and the landing will now steer onto the target. “Init Failed” says the target was lost again within those 2 s; the next sighting starts a new attempt. Until one succeeds the aircraft lands without the correction.

What to do, most likely first

1. The target was only glimpsed: too high, at the edge of the sensor's view, or while the aircraft was still turning.

   Check“Init Failed” and “Init Complete” alternate on the way down, and it locks once lower.

   FixStart the landing closer to directly above the target and inside the height the sensor is rated for.

2. The sensor loses the target for moments: sunlight on an infrared beacon, a marker too small, a slow camera feed.

   CheckIt never reaches “Init Complete”, even hovering low over the target.

   FixShade or strengthen the beacon, enlarge the marker, and make sure the sensor reports at least several times a second.

Parameters to look at