Mavic 2 Pro flipped over on back (after calibration of sensors)

[Deleted member 119592]

Day after calibrating sensors I flew under a bridge, when drone flipped over on back (video frame show leg upside down relative ground). I suspect I backed too close to structure. This happened at 6m height and without any warning. No visible marks on drone or propellers suggest a physical contact. Could calibrating backward sensors have failed? I am not sure I dare fly drone again.

 

[new2mavic]

There is no footage attached.

It will be more useful if you can provide the .DAT and .TXT files in the phone. Follow this thread to get the files : Flight log retrieval and analysis guide

 

[slup]

Hi there fellow countryman, welcome to the forum ?

You wasn't close to the bridge structure as seen on the 3D picture ... crash market with a red X, the log indicated a roll angle change from +4,3 degrees before & 156,3 degrees during the crash (also pitch & yaw shifted rapidly). The chart further below covers that within the red frame. The log indicates that both Obstacle Avoidance & Obstacle Avoidance RTH was inactive ... sure you had them activated?

Think they had some wire or perhaps cabling air-attached in that spot ... did you go there after the flight to look?

Might also add that keeping the drone within visual line of sight will make it easier & not so daring to fly ... & also within the laws & regulation.






**EDIT**

Now when you got the movie clip in place ... it's easy to see what you hit, not a mystery at all, this with log indicated Obstacle Avoidance not active.

 

[slup]

@martinmchugh ... checked your flight location a bit more, when talking about laws & regulations & to dare to fly.

To keep out of trouble I strongly recommend the Swedish Drone Map --> LFV Drönarkartan (RPAS, UAS, UAV) ... there you have the correct flight zones ... not in your GO4 app.

Look here ...

In the GO4 app DJI Fly Safe map says ... no zone what so ever.



But in reality ... and you were above 50m.

 

[new2mavic]

May be the drone hit a bird ?

 

[sar104]

May be the drone hit a bird ?

No - it backed into the concrete structure.

 

[new2mavic]

No - it backed into the concrete structure.

but the OP said "No visible marks on drone or propellers suggest a physical contact " .....

 

[slup]

but the OP said "No visible marks on drone or propellers suggest a physical contact " .....

This is what's seen in the clip just parts of a second before the M2 flips ... no bird, just the corner of the new bridge foundation being constructed.

 

[sar104]

but the OP said "No visible marks on drone or propellers suggest a physical contact " .....

I know what he said but, despite that, it conclusively hit the structure.

 

[OurAngryBadger]

I'm just wondering how did you recover the drone, did it not fall in the water? If so very lucky

 

[new2mavic]

I'm just wondering how did you recover the drone, did it not fall in the water? If so very lucky

The drone was able to recover by itself before hitting the water, like what is shown in this video at 5:08 :

 

[OurAngryBadger]

The drone was able to recover by itself before hitting the water, like what is shown in this video at 5:08 :

Wow that's amazing, I've always assumed if my Mavic 2 flipped over mid air it would be a goner.

Do they actually self recover quite frequently, or is it just very lucky?

 

[new2mavic]

Do they actually self recover quite frequently, or is it just very lucky?

If the drone is not broken in the impact then it should be able to recover even if knocked upside down. In the video above, one of the front arms of that M2Z has folded back and yet it was still able to recover.

 

[OurAngryBadger]

If the drone is not broken in the impact then it should be able to recover even if knocked upside down. In the video above, one of the front arms of that M2Z has folded back and yet it was still able to recover.

That's awesome. I've always been very worried about bird strikes ever since I had a flock of chickadees attacking my Spark a few years ago, and it seems a bird couldn't really damage a mavic 2, only knock it around unless it's like a hawk or eagle or something

 

[Deleted member 119592]

Just to clarify, guys...I really suspected I backed into the bridge construction. But, I was under the impression there were supposed to be sensors all around the drone to warn, stop and hover if things got too tight. None of that happened. And, there are no physical damages to the drone nor propellers. If it backed into a steel construction surely plastic propellers with such high RPM's would shatter?
The first replier mentioned "The log indicates that both Obstacle Avoidance & Obstacle Avoidance RTH was inactive ... sure you had them activated? " I certainly had not turned anything off. However, the day before this flight I was asked by RC to calibrate sensors which I did. Maybe the calibration screwed things up? After the calibration was done I was asked to restart drone, so it seemed I performed it correctly. App Menu also tells me Forward and backward sensors are enabled.
Drone recovered and I regained control.

 

[Deleted member 119592]

I'm just wondering how did you recover the drone, did it not fall in the water? If so very lucky

No. It recovered. 6m above water.

 

[Deleted member 119592]

If the drone is not broken in the impact then it should be able to recover even if knocked upside down. In the video above, one of the front arms of that M2Z has folded back and yet it was still able to recover.

Not sure that any arm was folded back. And, if a collision happened, surely propellers would have shattered? Plastic at such high speeds are very brittle-

 

[Deleted member 94047]

But, I was under the impression there were supposed to be sensors all around the drone to warn, stop and hover if things got too tight. None of that happened.

The M2P does not have a 360 obstacle avoidance. And even if it did, it would be poor judgment to totally rely on it.

 

[Deleted member 119592]

@martinmchugh ... checked your flight location a bit more, when talking about laws & regulations & to dare to fly.

To keep out of trouble I strongly recommend the Swedish Drone Map --> LFV Drönarkartan (RPAS, UAS, UAV) ... there you have the correct flight zones ... not in your GO4 app.

Look here ...

In the GO4 app DJI Fly Safe map says ... no zone what so ever.

View attachment 96204

But in reality ... and you were above 50m.

View attachment 96205

However, it does say that no special permit is needed for drones weighing up to 7 kg. I think the Mavic 2 weighs 0.9 kg. And I wasn't flying much above 6 m when I had the accident.
I shall check out the Drönarkarta. Thanks.

 

[Deleted member 119592]

Hi there fellow countryman, welcome to the forum ?

You wasn't close to the bridge structure as seen on the 3D picture ... crash market with a red X, the log indicated a roll angle change from +4,3 degrees before & 156,3 degrees during the crash (also pitch & yaw shifted rapidly). The chart further below covers that within the red frame. The log indicates that both Obstacle Avoidance & Obstacle Avoidance RTH was inactive ... sure you had them activated?

Think they had some wire or perhaps cabling air-attached in that spot ... did you go there after the flight to look?

Might also add that keeping the drone within visual line of sight will make it easier & not so daring to fly ... & also within the laws & regulation.

View attachment 96199

View attachment 96200


**EDIT**

Now when you got the movie clip in place ... it's easy to see what you hit, not a mystery at all, this with log indicated Obstacle Avoidance not active.

View attachment 96203

I cannot understand why Obstacle avoidance would be inactive. I did a Sensor calibration the day before this flight. Maybe it tampered with settings.