I was flying with my Phantom 3 Pro along the shore. In the beginning I could take photos and videos without any problems, but suddenly I received a warning:
Magnetic Field Interference. Exit P-GPS Mode.

The drone rapidly flew away from me (I think ATTI mode), as I couldn't control it, I pressed the Home Button.
The drone flew back and was very close to me from this point I tried to land it, but unfortunately it flew again away from me.

All this actions took a lot of battery power, and drone said:

Critically Low Power. Aircraft Landing.
It initatied this about 200 m in the open sea

R.I.P. Phantom 3 Pro

What did I do wrong, and how I can avoid these issues in the future ?

Thanks !

Were you near any large metal objects or was there anything between you and the drone?

Perhaps you can upload your flight logs so an assessment can be made by our learned members and DJI staff.
Apart from magnetic interference perhaps you also had high winds as you were near the shore where winds can be quite an issue.

Sorry about your loss.

There were no large metal objects around,  only a mountain was close by.
I m going to look for my flight logs.

http://www.phantomhelp.com/LogViewer/Upload/

(thank you msinger)

Sorry for your loss

Sync your flight records and I can look at your flight to see if I see anything unusual. Also provide your email used for the DJI account.
It's strange that RTH worked but after it came close to you it went the other direction.
Also, when you get critically low battery you can still fly by keeping the throttle up and you can fly all the way to zero%.

This happened to me once with my standard- u must make sure to calibrate and always record home point

You should of been able to maneuver a little bit after the auto land initiated. I mead I doubt you could have come back from 200m over the water, but you still have some control if you were to push up on the left stick to gain altitude and try. It would have go as far as it could until it went completely out of power. It is strange that it came back and then took off again? Sorry for the loss! Yeah, upload log files and maybe someone can offer some explanation.

Does salt water have any effect on any of the sensors?

Sp00nix Posted at 2017-3-29 11:09
Does salt water have any effect on any of the sensors?

If your drone took a bath in salt water you don't need to worry about sensors. The drone will be trash.
Even if you manage to bring it back to life by rinsing with fresh water, having it sit in rice for a few days etc:
Corrosion will kick in and you cannot rely on it anymore.

Sp00nix Posted at 2017-3-29 11:09
Does salt water have any effect on any of the sensors?

I would guess 'Yes'.

When I read "shore" it reminds me of my problems with the P3S:
Once on a concrete landing pier I got this "Magnetic Field" warning. Another time in a harbour with concrete surface.
Then again over a concrete scate park.

Have you been near/on concrete? I guess ferro concrete is a problem...

>Have you been near/on concrete? I guess ferro concrete is a problem...
No, there were just mountains, and far away a big antenna on the mountain peak, maybe that was the reason for problems.


>Sync your flight records and I can look at your flight to see if I see anything unusual. Also provide your email used for the DJI account.
>It's strange that RTH worked but after it came close to you it went the other direction.
>Also, when you get critically low battery you can still fly by keeping the throttle up and you can fly all the way to zero%.

I m going to figure out how to sync and do it. I had to chancel RTH, when it was close to me as I was worried that landing is not precise enough, ground was on the cliffs and not very stable.

Dronebird Posted at 2017-3-29 11:46
>Have you been near/on concrete? I guess ferro concrete is a problem...
No, there were just mountains, and far away a big antenna on the mountain peak, maybe that was the reason for problems.

I doubt it was the large antenna long ways away, but could be wrong. I have flown pretty close to some before, always aware and ready to react if something went haywire, but the only thing I ever experienced was a loss of signal for a bit, but no crazy movements. I understand now that you cancelled the RTH when it got close to you, so it must have somehow triggered another RTH because of the low battery, which for some reason was going to a different home point, and then initiated the auto land for critical low battery.

There were issues with the Standard resetting the home point but I haven't heard of that issue with the PRO. Was all of your firmware etc. up to date?

RicardoGray Posted at 2017-3-29 12:05
I doubt it was the large antenna long ways away, but could be wrong. I have flown pretty close to some before, always aware and ready to react if something went haywire, but the only thing I ever experienced was a loss of signal for a bit, but no crazy movements. I understand now that you cancelled the RTH when it got close to you, so it must have somehow triggered another RTH because of the low battery, which for some reason was going to a different home point, and then initiated the auto land for critical low battery.

There were issues with the Standard resetting the home point but I haven't heard of that issue with the PRO. Was all of your firmware etc. up to date?

>There were issues with the Standard resetting the home point but I haven't heard of that issue with the PRO. Was all of your firmware etc. up to date?

I never made a firmware update.

Dronebird Posted at 2017-3-29 12:08
>There were issues with the Standard resetting the home point but I haven't heard of that issue with the PRO. Was all of your firmware etc. up to date?

I never made a firmware update.

Fair enough. Just trying to help. Sorry man, it is strange for sure. Hope someone can offer some explanation.

Eric13 Posted at 2017-3-29 11:22
If your drone took a bath in salt water you don't need to worry about sensors. The drone will be trash.
Even if you manage to bring it back to life by rinsing with fresh water, having it sit in rice for a few days etc:
Corrosion will kick in and you cannot rely on it anymore.

'Corrosion will kick in and you cannot rely on it anymore.'

That does not have to be the end. Corrosion will only occur after a lengthy period in the air with salt on the aircraft. If you recover it from salt water, the first thing to do is rinse it thoroughly in fresh water, then place it in distilled ater for a couple of days. Follow that up by blowing the water out, let it dry and then use /dessicant or rice to dry it out. The battery will be ruined, so throw that away.

Important thing is not to let the salt water dry as that's when it forms crystals. That is why when they recover an orange Black Box from an aircraft they sela it with the water around it.

#shotxclvck Posted at 2017-3-29 09:53
This happened to me once with my standard- u must make sure to calibrate and always record home point

"This happened to me once with my standard- u must make sure to calibrate and always record home point"

These stories usually come from someone that calibrates the compass every flight.
Unnecessary recalibration of a perfectly good compass has the potential to cause problems.

Sorry to read about this.


RedHotPoker

Dronebird Posted at 2017-3-29 08:24
There were no large metal objects around,  only a mountain was close by.
I m going to look for my flight logs.

There were no large metal objects around,  only a mountain was close by.

I'm not saying this has anything to do with your loss, but DO be aware that some mountains have magnetic properties.  Airplane flight charts are usually marked with those areas because there is danger of aircraft compass error while in the area.

"What did I do wrong, and how I can avoid these issues in the future ?"

Without flight data you are only going to get people making guesses and most will be wrong or irrelevant.

Dronebird Posted at 2017-3-29 11:46
>Have you been near/on concrete? I guess ferro concrete is a problem...
No, there were just mountains, and far away a big antenna on the mountain peak, maybe that was the reason for problems.

As far as syncing the Go app flight records, you would tap on the cloud icon that's in the Flight Records section of the Go app. It's normally on the top of the page.

Thanks for your help, really awesome community !
I just uploaded my flight records

Please visit www.phantomhelp.com/LogViewer/Upload then post the link to your last flight log.


RedHotPoker

Geebax Posted at 2017-3-29 14:09
'Corrosion will kick in and you cannot rely on it anymore.'

That does not have to be the end. Corrosion will only occur after a lengthy period in the air with salt on the aircraft. If you recover it from salt water, the first thing to do is rinse it thoroughly in fresh water, then place it in distilled ater for a couple of days. Follow that up by blowing the water out, let it dry and then use /dessicant or rice to dry it out. The battery will be ruined, so throw that away.

I agree with everything Geebax says except
DON'T EVER USE RICE AS AN ABSORBANT it gets into loads of places , touches moisture then swells so it won't come out without further dismantling especially around the gimbal, motors, etc..

I have heard you can use dried peas??

This Phantom can't be dried anymore, as it landed in the sea
Gone...

Eric13 Posted at 2017-3-29 11:22
If your drone took a bath in salt water you don't need to worry about sensors. The drone will be trash.
Even if you manage to bring it back to life by rinsing with fresh water, having it sit in rice for a few days etc:
Corrosion will kick in and you cannot rely on it anymore.

I'm hoping this was a sarcastic response.

Dronebird Posted at 2017-3-29 23:50
Thanks for your help, really awesome community !
I just uploaded my flight records

Unless you post a link to the Phantomhelp.com report, no-one can see it to work out what realy happened.

Sp00nix Posted at 2017-3-30 04:14
I'm hoping this was a sarcastic response.

??  Sarcastic?
No it's just what happens when an electronic device with a live battery hits salt water.
Probably >99% would be sizzled in a microsecond.

Dronebird Posted at 2017-3-29 11:46
>Have you been near/on concrete? I guess ferro concrete is a problem...
No, there were just mountains, and far away a big antenna on the mountain peak, maybe that was the reason for problems.

IF it was a microwave link AND you flew into the path, there is always a possibility of interference. The coastlines use a lot of microwave links as the fiber lines tend to break when there are landslides - at least here in the PNW.

Dronebird Posted at 2017-3-30 03:50
This Phantom can't be dried anymore, as it landed in the sea
Gone...

RIP

Hoping your flight log will uncover some glitch

Here we go:

http://www.phantomhelp.com/LogViewer/7IFM601QFM6ORXO4OQWQ/

I reviewed the flight but I can not tell what happened, I see the GPS signal kept going in and out. Has it ever been crashed and you've never made any modifications have you?
It's best to start a ticket with support (if you haven't already) and let the flight data analysis team analyze the flight as they can better determine cause.Also you're flying over the ocean but you have your RTH altitude set to 200 meters. But that wouldn't cause any errors, just contribute to battery drain which was 6% as you were 300 meters offshore.
Maybe the default RTH altitude could have let you have enough battery to bring it back in.

Dronebird Posted at 2017-3-30 06:18
Here we go:

http://www.phantomhelp.com/LogViewer/7IFM601QFM6ORXO4OQWQ/

Right ... your flight data confirms your story.
It shows the flight starting normally and having no problems until 8:31 when it started showing Yaw errors.
This is a kind of compass error but usually caused by a malfunction.
The Phantom had been out over 800 feet without any error messages before this which suggests that the problem was not caused by a bad calibration or launch point.
The yaw errors continued until 9:59 and returned again at 12:28 (but compass errors this time).
As well as all the yaw error and compass error messages there were a few speed error messages which also hint at a malfunction.
The Phantom was uncontrollable while in the error state and eventually got to 10% and initiated critical low battery autolanding about 60 metres from home point.

It is highly likely that this was all due to a malfunction and not user error.
You should synch your flight record by clicking on the cloud icon in the app where you can see the flight records.
After you have uploaded it to DJI, contact their online support chat and tell them the story and see where they go with it.
Good luck with it.

DJI-Ken Posted at 2017-3-30 06:47
I reviewed the flight but I can not tell what happened, I see the GPS signal kept going in and out. Has it ever been crashed and you've never made any modifications have you?
It's best to start a ticket with support (if you haven't already) and let the flight data analysis team analyze the flight as they can better determine cause.Also you're flying over the ocean but you have your RTH altitude set to 200 meters. But that wouldn't cause any errors, just contribute to battery drain which was 6% as you were 300 meters offshore.
Maybe the default RTH altitude could have let you have enough battery to bring it back in.

I didn't do any modifications, but I also never flew it ATTI mode before

@Labroides Thanks for your great analysis !

Dronebird Posted at 2017-3-30 07:25
I didn't do any modifications, but I also never flew it ATTI mode before

@Labroides Thanks for your great analysis !

OK, no crashes either right?
The Flight Analysis department will figure it out.

DJI-Ken Posted at 2017-3-30 07:56
OK, no crashes either right?
The Flight Analysis department will figure it out.

And no crashes
Thanks!

Dronebird Posted at 2017-3-30 08:22
And no crashes
Thanks!

Ok, good.
Thanks

Dronebird Posted at 2017-3-30 06:18
Here we go:

http://www.phantomhelp.com/LogViewer/7IFM601QFM6ORXO4OQWQ/

Thanks... That can be a helpful aid...



RedHotPoker