Uncommanded descent Mini 3 Pro - lost into ocean

[ctiptonk]

Phantom Help Log: DJI Flight Log Viewer - PhantomHelp.com
Last 10s crash video:

I lost a Mini 3 Pro into the ocean, and can't figure out what went wrong. After a series of uncommanded descents/a momentary uncommanded left yaw and motor/prop errors. I attempted to use auto RTH (bad idea) and it unexpectedly yawed/spun hard left, rapidly lost altitude and went into the water. I was using MAS props, maybe it lost one blade, however it didn't appear to be vibrating. Here is a timeline of events:

5m 51s - Exited sport mode, 14ft above ocean. 10 mph wind, 84˚F. Sea was relatively calm; no observable wave caps or birds in area.
5m 52s - Sudden shock (?) uncommanded backwards pitch/left roll. I thought this might be due to wind, but there was no wind message in the app.
5m 57s - Begin full stick climb, switch to sport mode
6m 3s - AC descends 18ft despite continuous climb command
6m 9s - Reverse heading to return home. AC starts to recover altitude. Altitude varies despite full climb command.
6m 18s - 84ft alt
6m 20s - Release climb stick. AC descends to 70ft uncommanded.
6m 22s - Resume full climb command. AC continues to descend to 60ft then recovers slowly to 71ft
6m 31s - 120652 "Motor error. Check propellers and fly with caution!"
6m 32s - 30303 "Motor overloaded. Land promptly or cancel takeoff. Check whether motor and propellers are blocked or have frozen." These errors repeat several times.
6m 33s - Altitude recovers to 77ft. Release climb stick. AC resumes uncommanded descent.
6m 36s - 70ft. Resume full stick climb.
6m 22.3s - Was already in sport mode, pushed full stick climb
6m 49s - Altitude recovered to 97ft. Exited sport mode to attempt to address motor overload error. AC rolls sharply left uncommanded and begins to slowly descend.
7m 2s - AC now drifting left uncommanded, no forward travel despite full forward stick.
7m 5s - Activate RTH in hopes that RTH system will figure it out (in retrospect, this was a very bad idea). AC begins rapid descent despite being well below set RTH alt.
7m 9s - AC enters sharp uncommanded left roll and continues rapid descent. Momentarily rights at the last second
7m 12s - Splashdown, AC lost in unreachable deep water.

 

[Meta4]

Phantom Help Log: DJI Flight Log Viewer - PhantomHelp.com
Last 10s crash video:

I lost a Mini 3 Pro into the ocean, and can't figure out what went wrong. After a series of uncommanded descents/a momentary uncommanded left yaw and motor/prop errors. I attempted to use auto RTH (bad idea) and it unexpectedly yawed/spun hard left, rapidly lost altitude and went into the water. I was using MAS props, maybe it lost one blade, however it didn't appear to be vibrating. Here is a timeline of events:

Your drone was in steady forward flight when the trouble started at 5:51.1.
It was pitched forward at 30° and suddenly bucked backwards as far as 68° while rolling left 67° and losing directional stability.
Shortly after, it also lost stability it the vertical axis.
For the rest of the flight the drone was uncontrollable and erratic.
It was only able to roughly maintain height with with full left stick up.
When you engaged RTH and released the sticks, it was unable to maintain height and tumbled down into the water.

The inability to maintain height without full throttle together with the pitch, roll and yaw data suggests that the drone lost one propeller blade.
If it had lost a complete propeller, it would have spiralled downwards without you being able to hold height to some degree.

 

[Starz]

That’s not fun. Without a recovery, the most that can be determined would be in post number two. Was there a particular reason for the aftermarket props?

 

[ctiptonk]

Your drone was in steady forward flight when the trouble started at 5:51.1.
It was pitched forward at 30° and suddenly bucked backwards as far as 68° while rolling left 67° and losing directional stability.
Shortly after, it also lost stability it the vertical axis.
For the rest of the flight the drone was uncontrollable and erratic.
It was only able to roughly maintain height with with full left stick up.
When you engaged RTH and released the sticks, it was unable to maintain height and tumbled down into the water.

The inability to maintain height without full throttle together with the pitch, roll and yaw data suggests that the drone lost one propeller blade.
If it had lost a complete propeller, it would have spiralled downwards without you being able to hold height to some degree.

That’s what I thought might have happened; the only confusing bit is why it wasn’t vibrating. Can it lose one blade and still have steady video?

 

[ctiptonk]

That’s not fun. Without a recovery, the most that can be determined would be in post number two. Was there a particular reason for the aftermarket props?

Out of habit from when MAS props made my previous Mavic Pro significantly quieter. The MAS blades are much more fragile than factory, I won’t be using them again.

 

[Meta4]

That’s what I thought might have happened; the only confusing bit is why it wasn’t vibrating. Can it lose one blade and still have steady video?

The gimbal's job is to stabilise the camera and it does that very well.

 

[TonyPHX]

Looks alot like my MAS prop experience....don't get me wrong, i use them, love em, but well, stuff happens.