Crashed my Mavic air in cave water

[Sebastiaan van der Heijde]

Hi everyone,

Yesterday, I was making a hike to a beautiful cave in Vietnam. As I arrived, I was so thrilled about the beautiful nature and instantly grabbed my new Mavic Air, which I bought for my journey through Asia. I wanted to make an amazing shot by flying through the cave, which I now regret so much. As I was flying through the cave, the app reported “Max altitude approached. Wait for the GPS satellite signal recovery before ascend” (while only flying 3 meters above the ground) and “satellite positioning off. Fly with caution”. This had occured to me once before. So I wanted to fly the drone back to me so it would again be safe. Unfortunately, the drone started to move by itself, without me touching the controls. This resulted in crashing my drone to the wall of the cave, after which it fell into the water. As my heart was beating in my throat, I tried to swim as soon as possible towards my drone. Luckily, a Vietnamese local retrieved it out of the water before I could. As soon as he gave it to me (approx 2,5 minutes after crash), I switched off the battery and removed it. At the same time, my girlfriend had grapped the controller and later told me the camera was still functioning when I got the drone out. I tried to get as much water out of the drone as possible, blew in some openings as well, later I put it in a plastic bag, wrapped in a dry towel. As I got back to the homestay (approx 2 hours after crash), I immeadiately got a hairdryer and dried it (with good distance) for about 10 minutes on both sides. Then, I put it in a plastic bag filled with dry rice, of which they luckily have loads here in Vietnam! It’s still in this bag, outside, where it’s warm. I’m going to test it in about 2 or 3 days, but I am affraid it has been exposed in water for too long. Now I got 2 questions for the people reading my post.

1. Could this “maximum altitude reached” while flying just 3 metres above the ground be a production faillure? And could this help me to get a new drone if it is the case?
2. Do you have any recommendations on what I can do more with my drone which is currently surrounded by dry rice?

Hoping you guys can help!

 

[InvisibleName]

Flying inside a cave? Your drone would not receive any GPS signal and consequently go into ATTI mode - much harder to control if you've never done it before. I don't think you have any claim against DJI for operating inside a cave!

Was it a salt water cave? If so, 2.5 minutes immersion will most probably have killed it. Do you have DJI Refresh cover? If so, I think you are going to need to use it.

 

[Sebastiaan van der Heijde]

Flying inside a cave? Your drone would not receive any GPS signal and consequently go into ATTI mode - much harder to control if you've never done it before. I don't think you have any claim against DJI for operating inside a cave!

Was it a salt water cave? If so, 2.5 minutes immersion will most probably have killed it. Do you have DJI Refresh cover? If so, I think you are going to need to use it.

Luckily it was crystal clear sweet water. Do you think the drone has a chance to survive in that case?

 

[InvisibleName]

Luckily it was crystal clear sweet water. Do you think the drone has a chance to survive in that case?

Possibly, but I wouldn't recommend using the battery again.

Do you understand my point about flying without a GPS signal?

 

[Travisdavid]

Sorry for your accident. I am very sure there are many who would like to see your flight log uploaded here

 

[Sebastiaan van der Heijde]

Yes, I totally understand your point. Thank you for your explanation! I have to say that I was only about 3 meters inside the cave, I understand probably don’t have a claim towards DJI. Do you know if DJI easily repairs drones if errors like this one occur outside a cave leading to drone damage?

 

[InvisibleName]

Yes, I totally understand your point. Thank you for your explanation! I have to say that I was only about 3 meters inside the cave, I understand probably don’t have a claim towards DJI. Do you know if DJI easily repairs drones if errors like this one occur outside a cave leading to drone damage?

If the water was not salt, and you allow it to dry completely, there's a chance that no lasting damage was done (apart from the advice I gave you regarding the battery); there have been other cases discussed on here when this has been the case.

However, if it reports any errors when you try to power it up, I think you will need to send it to DJI. If you have DJI Refresh, then they would replace your drone with a new or refurbished drone. If you don't have refresh, they'll investigate & give you a quote - no idea what that might be, maybe someone else reading this may have some experience?

 

[Meta4]

1. Could this “maximum altitude reached” while flying just 3 metres above the ground be a production faillure? And could this help me to get a new drone if it is the case?

Definitely out of luck there.
Page 48 of your manual has this:

Unfortunately, the drone started to move by itself, without me touching the controls.

It didn't "move by itself, it drifted on the breeze and/or continued after you flew it.
That's what happens in atti mode, which is what happens when you fly somewhere the drone doesn't have a good view of the sky.

 

[Sebastiaan van der Heijde]

Sorry for your accident. I am very sure there are many who would like to see your flight log uploaded here

I tried uploading a screen recorded video, however it says “the uploaded file does not have an allowed extension”. As I don’t have a computer here as well, I could only attach these pictures of the flight log.

 

[Sebastiaan van der Heijde]

If the water was not salt, and you allow it to dry completely, there's a chance that no lasting damage was done (apart from the advice I gave you regarding the battery); there have been other cases discussed on here when this has been the case.

However, if it reports any errors when you try to power it up, I think you will need to send it to DJI. If you have DJI Refresh, then they would replace your drone with a new or refurbished drone. If you don't have refresh, they'll investigate & give you a quote - no idea what that might be, maybe someone else reading this may have some experience?

Thank you for your advice! I disposed the battery yesterday.

I don’t have refresh unfortunately. If it does not work when I try flying in 2 days, I will send it to DJI as soon as I can.

 

[Sebastiaan van der Heijde]

Definitely out of luck there.
Page 48 of your manual has this:

It didn't "move by itself, it drifted on the breeze and/or continued after you flew it.
That's what happens in atti mode, which is what happens when you fly somewhere the drone doesn't have a good view of the sky.

Allright, understood! I’m just going to pray for the drone to recover from its bath

 

[Deleted member 3792]

Sorry to hear about, but it’s the same stupidity as to fly under bridges close to water just for a good movieclip. The gps satellites are all over the sky in all directions and most of the time the drone can see 12-20 of those, if you then cover the receiving by flying under something (bridges, threes, rock, caves) for a few seconds there might not be enough with just 6-9 satellites and the drone goes in to atti-mode wich means manually flying, and then you must know how to solve it. A expensive learning money for the future.
I prefere an app called ”UAV Forecast” wich show me how many sats that is receivable right now depending on weather and wind and atmosphere.

 

[Meta4]

I prefere an app called ”UAV Forecast” wich show me how many sats that is receivable right now depending on weather and wind and atmosphere.

Unless you fly in an area where a chunk of the sky is blocked by terrain, or obstacles, you will always have plenty of sats anywhere you want to fly.
No need for an app to tell you that ... and the app can't tell if your sky will be blocked by obstacles.

 

[jeplane]

I prefere an app called ”UAV Forecast” wich show me how many sats that is receivable right now depending on weather and wind and atmosphere.

Weather or wind or atmosphere doesn’t affect satellites reception.

 

[InvisibleName]

Sorry to hear about, but it’s the same stupidity as to fly under bridges close to water

Not sure you need to be as abrupt as this! It was more 'naivety' / lack of knowledge that caused this

 

[Deleted member 3792]

Weather or wind or atmosphere doesn’t affect satellites reception.

Sorry to dissapoint you there but it can certainly do. Rain or to much humidity (fog) can do it, have happend to My self once. And then you have magnetic interference, both in the air and underground cables that can give you problems with reception/connection.

 

[Deleted member 3792]

Not sure you need to be as abrupt as this! It was more 'naivety' / lack of knowledge that caused this

Point taken!

 

[Meta4]

Sorry to dissapoint you there but it can certanly do. Rain or to much humidity (fog) can do it, have happend to My self once. And then you have magnetic interference, both in the air and underground cables that can give you problems with reception/connection.

GPS was designed to give all-weather navigation.
It wouldn't be much use if rain or fog could knock it out.

 

[InvisibleName]

Sorry to dissapoint you there but it can certanly do. Rain or to much humidity (fog) can do it, have happend to My self once. And then you have magnetic interference, both in the air and underground cables that can give you problems with reception/connection.

UAV forecast won't be much help in identifying magnetic interference - if only it could!

 

[Deleted member 3792]

GPS was designed to give all-weather navigation.
It wouldn't be much use if rain or fog could knock it out.

Have you ever seen satellite-TV when heavy rain falling? It’s like snowing on the screen and the receiption disappears. You seems to be that old (like me) that you were born before cable-tv.?