Mavic Jumped into the Ocean

[BroadFlight]

Hey guys - I thought I'd get your opinion as to whether this is expected behavior or not.

I was on a yacht recently, 26 miles off the coast and had the Mavic on the back of the yacht. (there is a flat platform there that's quite nice to take off from.)

I spun up the motors and moved myself to get into a better position on the back of the boat to see the drone as it flew. Without touching the controls, the drone then lifted off, tilted, hit the water, bounced and dived back into the water. It sunk in 30m of open ocean in which I wasn't brave enough to go fishing for.

DJI Support are saying it's my fault, even though the logs say I didn't touch the controls.

Is the drone supposed to stay on the surface it is on, with the motors spun up and no throttle applied? I couldn't find anything in the documentation about not flying off a moving platform?

Also, I know hand-launching probably would have prevented this, but I also didn't expect the mavic to take off by itself either.

Looking for some advice. Cheers!

 

[Mr. Salty]

It would really help to see your flight logs to see what happened.

 

[gnirtS]

Have to say i agree with DJI. Once the motors are spinning its in "flight" mode, the IMU is working to stop it "moving" and positioning keeping to an extent. As you've already worked out, from a moving object the only really sensible way is hand launch and hand recover.

 

[slowjohnny]

Have to say i agree with DJI. Once the motors are spinning its in "flight" mode, the IMU is working to stop it "moving" and positioning keeping to an extent. As you've already worked out, from a moving object the only really sensible way is hand launch and hand recover.

I would be cautions of hand launching and especially hand recovering the mavic from a moving object like a boat, I would be afraid of the boat surging up and getting hands, head, etc. into the props. I do understand what you are saying though, I don’t think I’d do that... to the OP... a variation of this though would be to take off immediately upon spinning up the motors and don’t expect it to “idle” there on the moving boat. I feel for your loss though, it is hard to “think” about what to do when something totally unexpected like that happens. Your post will hopefully help inform others about what can happen.

 

[Hollow Dog]

Take me out on your yacht and I'll show you how it's done.

 

[BrAinZ]

I’m no expert, but have a fairly logical mind.....
If the Mavic motors are running, one would assume that it’s going to try and keep itself in the same place. If it moves, then it’s logical for it to try and get back to where it was.
I feel your pain over something so simple (with hindsight!), but I would say not the fault of DJI.

I do think your feedback is good though, and going forward perhaps DJI could make that clearer in documents.

 

[gnirtS]

[QUOTE="BrAinZ, post: 317310, member: 464"
If the Mavic motors are running, one would assume that it’s going to try and keep itself in the same place. If it moves, then it’s logical for it to try and get back to where it was.[/QUOTE]

That's exactly what its doing, its trying to maintain position and the "ground" has moved from under it. Its the correct and expected behaviour from the drone so no fault there.

 

[gnirtS]

I would be cautions of hand launching and especially hand recovering the mavic from a moving object like a boat, I would be afraid of the boat surging up and getting hands, head, etc. into the props.

Its easy to do with minimal practice, launching is easier than catching, all you do is hold it above and clear. If you're worried about it bouncing a bit then stop the boat first and do it from the lowest part and stern so there is less wave motion. Ive never had a problem with it and i think its much safer than trying to take off or land from a boat (moving or not moving) with all the metal work, electrical wiring, interference, motion over water and so on.

 

[BroadFlight]

[QUOTE="BrAinZ, post: 317310, member: 464"
If the Mavic motors are running, one would assume that it’s going to try and keep itself in the same place. If it moves, then it’s logical for it to try and get back to where it was.

That's exactly what its doing, its trying to maintain position and the "ground" has moved from under it. Its the correct and expected behaviour from the drone so no fault there.[/QUOTE]

I was just frustrated that it's not listed anywhere. Being a novice, it's an expensive lesson to learn.

 

[BroadFlight]

The other thing that bothered me was that after the drone hit the water the logs showed inputs on the controls that were impossible for me to make. I don't even know how that's possible, so I'm still confused by the whole situation.