I wanna share with you guys the last moments of my Mavicair2 RIP

[DavidT_ NZ]

@Leo_mtz To get a more definitive analysis of your log file, post it in the Mavic Crash & Flyaway Assistance section of the forum and somebody will likely provide a thorough analysis of what happened.

What an excellent forum this place is for DJI drone pilot assistance!

 

[DavidT_ NZ]

In level flight and stable. In a turn, unless all props are at the same speed and pitch angle, other forces can happen. In my opinion, drone controls leave a lot to be desired. And, as you suggest, it is easy to inadvertently apply some control input, that can result in unfortunate circumstances.
Not flying too low is a simple solution but because photography is a mission of many flights,
getting close to the subject tends to happen. Sometimes with awkward results.

I also recall early DJI drone advice about flying low over water potentially affecting the downward sensors, although in this case, flying in Sport Mode offered no protection anyway. Better, perhaps, to fly in Normal Mode and then increase the replay speed in post editing for the desired viewing. And fly higher using the Air 2 digital zoom on the video, or gain some close up effect in editing. Very sorry to see a great drone lost but good to see the experience shared here. We all learn something.

 

[0Kajuna0]

I don't think the left stick is involved here. See the data synced with the video:

The recorded altitude suddenly increases before the crash, while the drone is not actually gaining altitude. I think the drone tried to compensate for the altitude change it (incorrectly) perceived by lowering its altitude, and that caused the crash.

There are users with more experience analysing crashes, but I would rule out a GPS-altitude error, I would rather suspect a barometer problem or, especially at that altitude, a problem with the downwards vision sensors. The warning at the top could also point in that direction: "Ambient light too weak. Vision and object detection systems not available. Fly with caution". Maybe the drone got confused when switching between vision altitude and barometer altitude? Again, not sure, others might have better insights.

I think it's worth sharing the video and the data with DJI, even without DJI Care.

 

[Leo_mtz]

Update:


Thanks for your comments and especially for the ones that recommend me to send my info to DJI support I reached out to them to request info for buying a spare they requested my flight log and concluded that garanty apply for the case so, they sent me a replacement free of charge It was a lot more than I expected. I did not believe it until it was here.
Thanks so much for all your comments I have learned a lot from this experience and will certainly avoid flying too low in the future

 

[EpicFlight]

All things being equal, I fail to see how choice of direction would affect altitude. (Again, assuming zero accidental stick input)

It doesn't, he's mistaking an issue with engine torque on single engine fixed wing airplanes that DOES cause an asymmetry in turning left vs right..

Quads are for practical purposes 360° symmetrical. The camera is what gives it a front.

 

[Pallidin]

Drones, be it DJI or other's, are amazing!
Flying cameras with stabilized footage.
I enjoy every flight.

 

[life.in.nb]

So I was taking pictures for my wedding invitations on the beach, everything was going great and after we finish up the session I decided to record a flight of the seashore (I have already did it once but I wasn't recording), I'm not sure what happened I was 3 to 4 meters above the shore turn around and it dropped down.

I'm still pretty sad about it, but I knew the risks when I bought it.

Here is the video

dji_export_1651469695029.mp4

drive.google.com

log:

DJI Flight Log Viewer | Phantom Help

Upload and view flight logs from your DJI drones

www.phantomhelp.com

btw I dont have dji care since It doesn't apply on Mexico, and I can't really afford a new one right now, do you know where can I buy a dji without the remote? maybe second hand or refurbished?

Looks like maybe a Vortex Ring State?

Same effect on helicopters that if you have forward motion, pull back to hover, and then it creates like a sort of prop wash, blades lose lift and down it goes. Or just descending too quickly too.

The only recovery is add some type of forward/back/side motion when it does lose lift.

I just had this question on my advanced exam in Canada lol

 

[KenCharuk]

Propeller driven aircraft tend to descend when turning rapidly, and the left turn is worse than a right turn for losing altitude. This accident happened in a left turn. If you practice turning at a higher altitude you may find the drone reacts differently in a turn one way than the other, which is a clue that tight turns at a very low altitude can very easily cause an accident.

Know this is an old thread but why would the direction of the turn matter on a quad? I am familiar with single outboard motorboat turns but there prop torque plays a role. That is balanced on a 4 prop drone.

 

[Peio64270]

I don't think the left stick is involved here. See the data synced with the video:

The recorded altitude suddenly increases before the crash, while the drone is not actually gaining altitude. I think the drone tried to compensate for the altitude change it (incorrectly) perceived by lowering its altitude, and that caused the crash.

I discover this thread already pretty old.
I think that flying so low over waving sea and imposing a brutal yaw in sport mode can explain everything. In Sport mode downward sensors are still working. Still you fly a straight line over the beach at a stable pitch of 28/30° these sensors locate the drone at 7/8" altitude very stable. But in less than 3 seconds you reverse the pitch by relaxing brutally the right stick (+30 to -30°) and immediately start a hard yaw which provokes a 10/30° roll.
Added together pitch and roll reach at this moment an angle >40° with respect to the sea surface, i.e. a 30 % increase compared to the previous stable situation. This increases by the same extent the distance of measurement by the downward sensors and "altitude" is falsely recorded as also increasing suddenly by roughly 30% (from 8" to 11"), inducing the drone to undertake a (fatal) descent at this very low altitude over the waves. The recording stops when the AC "thinks" it is at 8" when it might be at only 3" or less, taking into account the lag in data transmission.