Mavic 2 Pro Down: Cause Undetermined

[Totem]

On November 20th I attempted to map a 26-acre oyster bed lease area using the Drone Deploy (DD) mapping app and a DJI Mavic 2 Pro. The M2P did not make it back to me and I cannot figure out why. About 95% of the flight was over a mud flat, unfortunately the failure occurred over the navigation channel. I will forgo discussing recover effort to be brief but the M2P was not recovered. Drone Deploy evaluated the flight records from the tablet and suspect the problem is rooted in the hardware since the GPS Signal Score was a mere 10.2 out of 100. I had 17 satellites so this is a mystery to me. DJI will not evaluate second party flight logs. Bird strike is a possibility, though three of us watching the drone fall do not believe so. One oddity of note was that this was a two battery mission and instead of turning towards home for the battery change, the M2P began flying backwards and slow during automated RTH. I turned on Sports Mode for the flight back. Ops seemed normal for about 2,000 feet then the M2P appeared to just fall from the sky... and into the navigation channel. This was perhaps the 20th flight for the M2P and the battery was at 22%. This particular battery likely only had 2 or 3 charges. Your thoughts and comments will be appreciated.

 

[Totem]

AIRDATA:
Drone Deploy Flight Record

Go4 Flight Record

 

[Totem]

Mission launch site.

 

[Totem]

Last one.

 

[Daggad]

Prop failure maybe ?

 

[ff22]

Prop failure maybe ?

How often does that happen? I guess I should inspect them more carefully.

 

[squashpile]

Signal looks pretty bad and I see amperage spikes. I don't think I have ever seen that on my batteries.

 

[Totem]

I am open to any explanation backed up by some flight log data. The M2P fell like it lost a prop...but would that cause it to RTH backwards? I think the answer lies inside the drones computer. Unfortunately that is swimming in Davy Jones Locker.

 

[sar104]

I am open to any explanation backed up by some flight log data. The M2P fell like it lost a prop...but would that cause it to RTH backwards? I think the answer lies inside the drones computer. Unfortunately that is swimming in Davy Jones Locker.

It was flying south and facing south on the way back - it was not flying backwards. It does look a lost like a lost prop or ESC failure:



The pitch, roll and yaw oscillations are consistent with propulsion failure on one motor, but it's not definitive.

 

[crlmjohnson]

what application or software should I used to open the flight log files?

 

[Totem]

what application or software should I used to open the flight log files?

I used the AirData service. They offer a 30 day free trial and reasonable monthly costs after that.

Drone Data Management and Flight Analysis | Airdata UAV

 

[Totem]

It was flying south and facing south on the way back - it was not flying backwards. It does look a lost like a lost prop or ESC failure:

View attachment 55759

The pitch, roll and yaw oscillations are consistent with propulsion failure on one motor, but it's not definitive.

View attachment 55758

 

[Totem]

Okay, so I was operating under the assumption that the orientation of the aircraft was indicated by the blue triangle. This icon was tracking along normal until the automatic RTH. This is where the aircraft appeared to be flying backwards until I switched to Sport mode. I then turned the aircraft to the forward orientation and flew for and estimated 2,000 feet before the accident. I trust your assessment, I just want to be clear on the icon orientation being faulty.