High altitude variation while flying ALT_HOLD

Hi all,

I have been using this drone for quite some time now, but recently, I have been experiencing a weird altitude sway while flying in ALT_HOLD mode. I have been trying to understand what is causing this, but I have yet to find the root cause.

This has happened twice. The first time it happened, it continued to behave like that for 5-6 flights, then it recovered and started behaving normally.

Now, after a few months, I am experiencing the same altitude issue again.

The drone altitude sways very highly. For instance, when flying at a height of 1.5 meters above the ground, the drone sways by at least +/- 0.5 meters. I am primarily using a rangefinder to measure the altitude, as the barometer’s performance is subpar.

I have attached a log file from the ardupilot for your reference.

00000003.BIN (408 KB)