Mavic mini loosing control mid-air?

[rafare]

Hey guys,

First of all, there was no loss here, but I really wanted to figure it out what happened.

1- Contacted "ATC" of the airport that is less than 500m from my take off, they just told me to stay parallel to the runway, but theres almost no movement as this is a very small private airport.
2- Checked windspeed with UAV forecast, it was about 10km/h with gusts of 18 km/h at 20m height
3- Before take off it prompted me to calibrate compass, The first calibration was unsucessful, for the second I walked away from the spot I was a few feet just to make sure it wasn't some type of metal underneath the grass, and it calibrated sucessfully
4- Did some flying near the take off point just to make sure wind was OK.
5- I Flied for about 300m in direction of the canyons
6- After strong wind warning I immediately turned back to return to the home point.

This is when this incident happened. Time of incident: approx. 7:47

I was flying home in sport when suddenly the camera started pointing down and to the left of the actual heading (I know sometimes the gimball have trouble with perpendicular wind), But my girlfriend had line of sight of the drone itself and told me that the drone actually bounced around. Looking at the data it really did.

I'm pretty sure this is related to wind, but I really just to make sure that this is the correct explanation. I was really afraid of it flipping upside down and turning off the motors, consequently falling like a rock. This could be possible?
Is this a normal behavior for a moderate wind?
If someone has the airdata 360 plan, can upload it just to see what kind of windspeeds the MM was facing at flight?

Checked props afterwards and it appeared to be 100% normal.

Thanks in advance guys

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[Meta4]

This is when this incident happened. Time of incident: approx. 7:47
I was flying home in sport when suddenly the camera started pointing down and to the left of the actual heading (I know sometimes the gimball have trouble with perpendicular wind), But my girlfriend had line of sight of the drone itself and told me that the drone actually bounced around. Looking at the data it really did.

I'm pretty sure this is related to wind, but I really just to make sure that this is the correct explanation. I was really afraid of it flipping upside down and turning off the motors, consequently falling like a rock. This could be possible?
Is this a normal behavior for a moderate wind?

There was something unusual in your flight starting at around 7:48.1 when you were flying at full speed in Sport Mode on a heading of 251°.
The mini rotated about 110° anticlockwise and then back again to resume its original heading at 7:51, without any corresponding joystick input to explain the move
There was no significant affect on the drone's height.

This was not the kind of thing that's normally seen in flight and it's not easily explainable as an effect of wind.
I can't see an obvious cause.
Perhaps @sar104 might find something looking deeper into the flight data.

 

[rafare]

There was something unusual in your flight starting at around 7:48.1 when you were flying at full speed in Sport Mode on a heading of 251°.
The mini rotated about 110° anticlockwise and then back again to resume its original heading at 7:51, without any corresponding joystick input to explain the move
There was no significant affect on the drone's height.

This was not the kind of thing that's normally seen in flight and it's not easily explainable as an effect of wind.
I can't see an obvious cause.
Perhaps @sar104 might find something looking deeper into the flight data.

Just to fresh your memories. My Mini is the one that had this discussion:

Mavic Mini strange behavior after take off, drifted away.

Hey guys, something very strange happened today. To summarize, just after take off the drone drifted to the right without any commands from my end, I'm flying from my "backyard" that is very small so I tend to fly straight up initially to clear all trees and houses around and then continue with...

mavicpilots.com

I already saw the mini “lose” control on the roll/yaw axis before at very strong winds, up to 30-40kmh gusts, but was not that hard.
I was almost sure that it would fall from the sky today.
The gimbal on mine keeps disarming, doing like a reset procedure under moderate winds and specially hard turns in sport mode. In this flight it happened quit times. Im considering contacting DJI with this logs.

 

[sar104]

There was something unusual in your flight starting at around 7:48.1 when you were flying at full speed in Sport Mode on a heading of 251°.
The mini rotated about 110° anticlockwise and then back again to resume its original heading at 7:51, without any corresponding joystick input to explain the move
There was no significant affect on the drone's height.

This was not the kind of thing that's normally seen in flight and it's not easily explainable as an effect of wind.
I can't see an obvious cause.
Perhaps @sar104 might find something looking deeper into the flight data.

That log gives me a headache just looking at it. The aircraft is being thrown around wildly in sport mode for most of the flight - I'm not surprised it had a dizzy spell. The wind was not the issue and there was no impact in the air. The proximate cause was a sudden FC-commanded deceleration of the right rear motor at 468 seconds after the throttle was centered from full descent during full forward elevator. The IMU and compass both recorded exactly the same resulting yaw, so it's not clear what caused the FC to do that.

 

[boblui]

My Mini has once exhibited the same behavior. In a full-speed forward flight in sport mode, the nose of the craft swang without any rudder input but the orientation was always self-restored quickly. The movement can be seen in the video feed and also the flight logs. I have tried to reproduce it in the same day but the behavior didn't show up again. I wont worry too much about it.

 

[BudWalker]

My Mini has once exhibited the same behavior. In a full-speed forward flight in sport mode, the nose of the craft swang without any rudder input but the orientation was always self-restored quickly. The movement can be seen in the video feed and also the flight logs. I have tried to reproduce it in the same day but the behavior didn't show up again. I wont worry too much about it.

View attachment 108797

The next time that happens can you retrieve the fc_log.log from the SD card? It's a .DAT that has a lot more info than the .DAT recorded by the Fly App. You'll need to retrieve it prior to the next power up.

 

[rafare]

Thanks guys.
I think Ill contact dji and supply this logs. This incident could be catastrophic with the motors turning off.

Im away from my PC today. Can anyone check what was the maximum and minimum angle of pitch/roll in my incident please?

What I could do to prevent this in the future? Maybe not combining full throttle with full pitch in sport?
Could old props be a factor? FC issue?

 

[rafare]

That log gives me a headache just looking at it. The aircraft is being thrown around wildly in sport mode for most of the flight - I'm not surprised it had a dizzy spell. The wind was not the issue and there was no impact in the air. The proximate cause was a sudden FC-commanded deceleration of the right rear motor at 468 seconds after the throttle was centered from full descent during full forward elevator. The IMU and compass both recorded exactly the same resulting yaw, so it's not clear what caused the FC to do that.

I really do not know much about drone data analysis. Could the FC be compensating for the yaw at 467 s? I don't know what frequency the data from the engines are updated, but that appeared to be a consequence of the movement.

As I said, I know next to nothing and still learning with you guys.