Automatic launch of parachute failed

We did a flight test where we wanted to check the automatic launch of the parachute in case of a motor failure. After disconnecting a motor, first the drone made a few tumbles but then settled in a relative level spin and no automatic launch occured. Eventually we succesfully manually deployed the parachute and made a safe landing.

The question is why that the automatic launch of the parachute failed. I’ve reviewed the logs and from what I can see is that the angle error (effective angle - desired angle) was larger than 30 degrees for more than a second, with a decreasing barometer altitude and above the minimum altitude of the parachute. So, according to me all conditions for an automatic launch should have been fullfilled. Does anyone have an idea what I’m missing that prevented the launch or how I can best debug this without having to do 10 more drops? below is a link to the flight log for additional information.

PS: also the critical sink rate was set, but the drone did not reach this because it was still powered and doing a “stable” descent at a lower rate (after potential thrust loss detection)

Many thanks in advance for the help!


2022-05-06 16-50-28.log.param (18.5 KB)