From auto analysis I get this Test: PM = FAIL - 19 slow loop lines found, max 15.80% on line 491. Can’t find any info on what it really means. This is a new 1300mm X8 with U8pro 170kv motors and 28" propellers, so I was prepared for a less than normal first flight, but what I got felt pretty odd in the air. I wanted it flying ok before I tried autotune. Seems like it’s barely keeping itself up in the air, hard to describe. Looking at the roll, pitch and alt makes me really wondering what’s up and maybe this slow loop has something to do with it.
I have this same question… If it means the CPU in the flight controller is too “saturated” that it is not completing a cycle fast enough then at what point should we be concerned? 20%? 30%?
Matt
A little concerning lol! May that’s why it looks like it’s about to fall out of the sky! Too bad you can’t get a Pixhawk with an Octo core, ssd drive and 64gb of ram. Only get this on the X8 though, not my hex.
I have seen quite a few people getting those errors, not seen an answer on that.
Your copter is quite different to what the defaults were probably designed for, so probably just needs tuning.
Your roll and pitch seem to be trying to match desired.
Could simply be too lightly loaded right now. It’s meant to carry about 7kg, but the payload wasn’t ready to fly. So I strapped a brushless gimbal with a sony Nex5n on it for a little ballast… At a whole 1.2kg lol. That’s a whole 13.2kg, but the motors at 50% wold be putting out 16kg of thrust. Better get some weight on this thing.
From memory of your log it doesn’t look like its lightly loaded. If I recall your rcouts were about 1600 so over half throttle for the esc. Have you calibrated your ESC?
sent from my phone so apologies for any typos
I can’t imagine I forgot to calibrate them. I’ll have to check that out. The motors are barley working at hover.
even on 6s a 170kv motor isn’t going to spin that fast, about half as fast as my 700kv on 3s, and they are hardly screaming.
They will spin as fast as they need to hover, and with 28" props probably not very 
I have the same problem with my hexa with 4.8 Kg overall weight and my Esc have been calibrated.