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DRONE DISCONNECTS / LOSES SIGNAL WITHIN VIEW OF PILOT, THEN SPLASHES INTO 120meter DEEP ALPINE LAKE...

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MAVJON 2112

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DRONE DISCONNECTS / LOSSES SIGNAL WITHIN VIEW OF PILOT, THEN SPLASHES INTO 120meter DEEP ALPINE LAKE... yes, it was that simple. I was in the middle of NOWHERE. NO cell service, no power lines, and flying over Lake Omak in Omak, WA where I was nearly the only human being outside, at least within the entire side of a 6 mile/10kilometer long lake. I launched from a 300 foot / 100 meter high cliff. I followed the reading on the screen which displayed I was flying at an altitude of (- 60) feet altitude lower than the launch point, meaning I had a minimum of 150 to 200 feet of space below the drone while in flight above water. While I paused in flight, I simply began to fly slowly and steadily in reverse wanting to find a starting point for a clip of video on this gorgeous lake WITH NO WIND (the water was like a mirror reflecting the mountains above it no ripples let alone no crests.) While backing in flight, and watching my altitude, within 20-30 seconds of flight, my signal was lost and I received the black and white still of the last known view. I hit the RTH button instantly. At time of lost signal, I was less than 2 minutes away from the launch point and I had 22 minutes of battery flight left. SO, all is well, right? WRONG. Despite hitting RTH, despite the fact I had immediately stopped flight after signal loss and hit the RTH, after waiting over 30 minutes, the drone NEVER RETURNED.

UPDATE POST OF ORIGINAL POSTING:

IMPORTANT NOTES OF FLIGHT CONDITIONS:
1) I had just taken off, and I JUST recharged that battery. I had EVERY bit of 22 minutes left when craft disconnected. I had been in flight maybe 6-8 minutes.

2)Battery locked fully in place, craft stayed level, flight was slow, NO wind, NO rain, Sunny outside, NO obstacles.

3) NO obstacles around ... lake is HUGE, 6 miles long, 1 and 2 miles wide. I was not even a 1/4 mile, 200-300 meters away from craft standing in the OPEN VIEW. DIRECT line of sight with craft.

4) Craft launched at 250-300 feet above water from a cliff with line of sight to craft. Craft lowered (according to Smart Controller) -60 feet. This means 300-60= 240 feet above water. OR 250-60= 190 feet above water.

5) I will admit, from the looks of the trees relative to what showed on the Controller Monitor, it appeared to me I was closer to 80-100 feet off the water. HOWEVER, this should be NO ISSUE. Per DJI, flight over water is ONLY recommended in the reference of "do not fly 2 meters from above the water". In many places, very vaguely, including the manual, the warning is "do not fly above bodies of water, reflective, or transparent surfaces". BUT, this, again, is ONLY relative to flight at 2 meters above those surfaces according to one warning.

OBVIOUSLY, flying at 100 feet / 30 meters above water should have ZERO impact on positioning if the pilot has done as I have and maintained reference to his flight and paid extreme focus on use of flight controls. I ONLY REVERSED flight, NOT lowering the craft.

I do believe the issue to be aimed at a firmware problem now.

THANK YOU to those who have replied.

TO ALL READERS, please read this thread. I TRULY BELIEVE the outcome of this WILL HELP ALL OF YOU in understand possible issues with firmware, disconnects, and crashes.

THIS CRASH OF MINE IS A VERY VALID ISSUE TO BE ADDRESSED!!!


I have read the Mavic 2 may have a known issue with low altitude flight over water. I have seen a few youtube videos showing this happening to other pilots (just 2 that I have seen).

QUESTIONS TO OTHER PILOTS:

QUESTION #1 - do any of you know this to be a possible issue?
QUESTION #2 - do any of you have any pointers, tips, clues, questions, input as to what the heck happened to me?

STATEMENT - I wish to hold DJI responsible. I AM SICK of fly away issues & android issues using DJI apps that nearly crashed me twice due to DJI apps crashing midflight causing fly aways before upgrading to a SMART CONTROLLER (which is THEE only way to fly, though it is still problematic with update messages that are false). False messages on both smart controller and android based flights are confusing. On android, it would end up in a fly away though firmware was updated and matched between controller, android pad, and drone. On the day of my loss, MY SMART CONTROLLER was up to date and matched my drone. However, just before flight, a mismatch warning popped up (again) for just less than 2 seconds, then read firmware matched. 5 minutes later, my drone disappeared using an 800 dollar Smart Controller.... RIDICULOUS!!! I feel DJI should research my flight, find it is their fault, and replace my drone.

QUESTION - How can I best press DJI to replace my drone?

Thank you,
Jon
 
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The best way to work out what happened in a drone incident is to analyse the recorded flight data.
But in this case there is none so all we can go on is your description of the incident.
DRONE DISCONNECTS / LOSSES SIGNAL WITHIN VIEW OF PILOT, THEN SPLASHES INTO 120meter DEEP ALPINE LAKE... yes, it was that simple.
Was it really that simple?
Drones often lose signal, but that doesn't cause the drone to fall from the sky.
It leaves the drone hovering and the loss-of-signal action chosen by the flyer is initiated.
That's usually the default setting of RTH.

A much more likely explanation for your incident, is that there was a sudden loss of power and your drone fell from the sky.
While backing in flight, and watching my altitude, within 20-30 seconds of flight, my signal was lost and I received the black and white still of the last known view. I hit the RTH button instantly. At time of lost signal, I was less than 2 minutes away from the launch point and I had 22 minutes of battery flight left. SO, all is well, right? WRONG. Despite hitting RTH, despite the fact I had immediately stopped flight after signal loss and hit the RTH, after waiting over 30 minutes, the drone NEVER RETURNED.
If you've lost signal, pushing the RTH button won't work.
If the drone had lost power and fallen, pushing the RTH button won't bring it back.
Did you have the drone in sight?
Did it hover after losing signal?
Did you see it fall?
I have read the Mavic 2 may have a known issue with low altitude flight over water. I have seen a few youtube videos showing this happening to other pilots (just 2 that I have seen).
The concerns you mention are about the downward looking VPS sensors.
They have a range of only 30 feet and were not involved in your incident where the drone was 240 feet above teh water.
STATEMENT - I wish to hold DJI responsible. I AM SICK of fly away issues & android issues using DJI apps that nearly crashed me twice due to DJI apps crashing midflight causing fly aways ... On android, it would end up in a fly away though firmware was updated and matched between controller, android pad, and drone.
Did you look into the causes of those previous incidents?
If you think your drone was flying away, that suggests you haven't.
STATEMENT - I wish to hold DJI responsible. ...
On the day of my loss, MY SMART CONTROLLER was up to date and matched my drone. However, just before flight, a mismatch warning popped up (again) for just less than 2 seconds, then read firmware matched. 5 minutes later, my drone disappeared using an 800 dollar Smart Controller.... RIDICULOUS!!! I feel DJI should research my flight, find it is their fault, and replace my drone.
QUESTION - How can I best press DJI to replace my drone?
All you have to do is provide evidence that demonstrates that a DJI fault caused the loss of your drone.
But it's unlikely that the flight data recorded on your controller will have any.
And because you chose to fly in an area where failure would result in an unrecoverable drone, you are going to be out of luck.
 
STATEMENT - I wish to hold DJI responsible.
Sorry to hear your misfortunes. If this was indeed a case of equipment malfunctioning, I think you will have a good chance of getting DJI to replace your lost drone; we have seen several instances of DJI doing that from various posts in this forum. However, there will have to be evidence showing that and that can only be ascertained from the flight log. Upload the flight log for the flight and I am sure there are a lot of people here who can identify what went wrong and whether it was a case of a faulty equipment.
 
You flew over a cliff, then lowered the drone below the cliff top and reversed. Any chance the loss of signal was due to blocking direct LOS between the RC and drone?
 
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You flew over a cliff, then lowered the drone below the cliff top and reversed. Any chance the loss of signal was due to blocking direct LOS between the RC and drone?
If he just lost signal, the drone would have come back.
 
Is there no flight log? That’s your only hope with a DJI.
 
Is there no flight log? That’s your only hope with a DJI.
There will be a flight log .. right up until the drone lost power.
But the problem with a sudden loss of power is that the flight log shows everything was fine until it just stops.
 
There will be a flight log .. right up until the drone lost power.
But the problem with a sudden loss of power is that the flight log shows everything was fine until it just stops.
if that is indeed what happened ... but perhaps operator error shut down engines ..we simply do not know but the logs are the only viable source of data to give an indication of anything ...
 
but perhaps operator error shut down engines
But he said that he was just backing the drone up, not flying all over the sky like a crazy monkey.
You cannot accidentally shut down the motors gently backing up.
 
We need the log as a minimum & as a bonus, answer from the OP if he had visual on the AC & could see it either hover or fall after the control went black ...
 
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Sorry about your loss.
I had a similar incident recently. Mavic 2 Pro, Smart Controller. Well within range but no visual, all of a sudden the screen goes B&W of the last picture. The app had crashed, but the connection LED was still green (which is something I will now always look at for diagnosing what goes wrong). After trying RTH and other things for a while I closed and restarted the app, and picture came back in colour, the drone was still in the same place, hovering. With everything working normally, I flew it home safely. If the battery had drained to 0 it would have dropped into the brackish waters of the Tudor Creek mangrove forest.
Reason for the app to crash is unknown. I was taking quite a bit of pictures Raw+JPEG quickly after another, whilst slowly flying and panning. Perhaps that could cause a memory stack to overflow and crash the app ?
 
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The title says OP was flying VLOS, but details suggest otherwise. I realize even if one was within VLOS, when taking nice shots one would be concentrating on the screen.

The height indicator can be as much as 10ft off. If you were way over that over the lake then it wouldn't be relevant but when close to obstacles, ground, water, it can give you may be closer than you think. It operates by barometer after all. Best to eyeball your clearance.
Over water the VPS may not detect water surface but rather the surface below the water so again eyeballing your clearance and behavior is best.
 
The title says OP was flying VLOS, but details suggest otherwise. I realize even if one was within VLOS, when taking nice shots one would be concentrating on the screen.

The height indicator can be as much as 10ft off. If you were way over that over the lake then it wouldn't be relevant but when close to obstacles, ground, water, it can give you may be closer than you think. It operates by barometer after all. Best to eyeball your clearance.
Over water the VPS may not detect water surface but rather the surface below the water so again eyeballing your clearance and behavior is best.
I appreciate your time you have spent here, and I appreciate the response. Details in my description show 1) launch point 300 feet above water 2) flew down to -60 feet from start point 3) this is 240 feet above water, NOT 10 feet !!! However, you made a VERY IMPORTANT point regards to the Vision Positioning System (VPS) if GPS is not working due to the desolate location, perhaps the drone itself was trying to use its own visual positioning system (VPS) as a means of reporting position and it failed. At time of loss, I was probably standing 300-500 meters horizontally from the drone, but almost all of that was over crystal alpine water on a sunny day.

Bottom line, out of all the replies, your effort in mentioning 3 letters says a lot to make me think ... VPS. DANG IT! I did not understand the performance of the VPS specifically and NO manual or info is made ready to pilots regarding how VPS may fail to function properly in above water flight conditions. I did research after the splash to find out of this issue...and it is an actual issue noted in various technical websites. BUT, DJI does not make this a specific warning and does not explain VPS at all concerning this condition.

DJI does offer vague info in the manual, however, which, again, is vague. Notice how there are very obvious conditions to NOT perform flight, like over people, & power lines. BUT, it lists to avoid obstacles, trees, and bodies of water which is HIGHLY subjective and vague. We all fly between trees or over trees to some extent, we all fly around obstacles (which is very vague) and bodies of water is very subjective and relative to flight and there are SO MANY videos of flight above water. I fly over water all the time, BUT I stay within a 2 minute return flight with 15 minutes left on battery power meter and NO wind (very important factor... NEVER fly in wind over water or without very ample battery charge left.)

FROM THE MANUAL:

DJI Mavic 2 Pro/Zoom User Manual v2.0 PDF, page 57, under the Heading "FLIGHT ENVIRONMENT REQUIREMENTS", lines 3 and 6 say the following:

3) Avoid obstacles, crowds, high voltage power lines, trees and bodies of water

6) The Mavic 2 cannot use GPS in Polar Regions. Use the Downward Visioning System when flying in such lo
cations.

SO, in essence, I would be at fault in flying over water??? Is this correct???

My arguments:

1 - Concerning Instruction 3 - Many pilots fly over water, and I was at least 200 feet above water. Why would it just go down and down in flight until taking a splash into the lake when I am only reversing the drone, and CAUTIOUSLY I might add.

2- Concerning Instruction 6 - I assumed earlier GPS may not have been working. However, according to this instruction, the only concern for loss of GPS would be in the North Pole or South Pole. I am in the Continental USA. GPS should have given me proper flight data then, correct??? And it reported I was only down 60 feet from a point of 300 feet. Lets say I was only 200 feet at the launch point. This still gives me 140 feet above the flight deck / lake water. The drone should not have splashed!!!

Again, Thank you for your input... it sent me on a good path of evaluation.

Jon
 
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I appreciate your time you have spent here, and I appreciate the response. Details in my description show 1) launch point 300 feet above water 2) flew down to -60 feet from start point 3) this is 240 feet above water, NOT 10 feet !!! However, you made a VERY IMPORTANT point regards to the Vision Positioning System (VPS) if GPS is not working due to the desolate location, perhaps the drone itself was trying to use its own visual positioning system (VPS) as a means of reporting position and it failed. At time of loss, I was probably standing 300-500 meters horizontally from the drone, but almost all of that was over crystal alpine water on a sunny day.

Bottom line, out of all the replies, your effort in mentioning 3 letters says it all ... VPS. DANG IT. I did not know of this and NO manual or info is made ready to pilots such as myself who do not fly every day, but are still VERY cautious and NOT knowing something due to POOR communication from vendors. THE MOST that is said in the manual is this...

DJI Mavic 2 Pro/Zoom User Manual v2.0 PDF, page 57, under the Heading "FLIGHT ENVIRONMENT REQUIREMENTS", lines 3 and 6 say the following:

3) Avoid obstacles, crowds, high voltage power lines, trees and bodies of water

6) The Mavic 2 cannot use GPS in Polar Regions. Use the Downward Visioning System when flying in such locations.

SO, in essence, I would be at fault in flying over water??? Is this correct???

My arguments:

1 - Concerning Instruction 3 - Many pilots fly over water, and I was at least 200 feet above water. Why would it just go down and down in flight until taking a splash into the lake when I am only reversing the drone, and CAUTIOUSLY I might add.

2- Concerning Instruction 6 - I assumed earlier GPS may not have been working. However, according to this instruction, the only concern for loss of GPS would be in the North Pole or South Pole. I am in the Continental USA. GPS should have given me proper flight data then, correct??? And it reported I was only down 60 feet from a point of 300 feet. Lets say I was only 200 feet at the launch point. This still gives me 140 feet above the flight deck / lake water. The drone should not have splashed!!!

Again, Thank you for your input... it sent me on a good path of evaluation.

Jon
If you want to achieve something more then just a lot of speculation you need to share your flight log ... if something other then a sudden power loss happened to your AC the true reasons will most probably be in there.
 
Me Too 4weeks ago total diconnect on MP2 gone never to be seen again to cut a long story short i today got a 30% off voucher of DJI for a new one, also insurance laughed at me aswell flyaways not included.
 
Sorry you lost your bird.

You stated that you had "22 minutes of battery flight left" -but perhaps you had 22% remaining. The last 25% goes very quickly. I always return well before 25%.

Also, I have inserted my battery til I heard the "click" but then noticed that BOTH sides were not fully locked. I now always check battery after attaching to be sure it's firmly in place.

Sounds like there were no wires or power lines over the lake. But the rear sensors would probably not detect either of those. I'm assuming you are certain that you could not have reached the other end of the lake? As you could have hit a tree, or other obstacle. Leafless trees are invisible to the sensors. I've been there. Did you check the map to be sure you were in the middle of the lake, not the other end?
 
I also just read on the DJI website the conditions to NOT fly in. Interesting. It says do not fly over reflective, transparent, or water surfaces. BUT then offers more detail and states "do not fly at 2 meters above water". OMG. 2 meters... I would NEVER fly that low above the ground. I was 50 meters or higher when my drone quit!!! Now I think my issue may have nothing to do with being over water. I was in a flight much above what is safe.
 
Sorry you lost your bird.

You stated that you had "22 minutes of battery flight left" -but perhaps you had 22% remaining. The last 25% goes very quickly. I always return well before 25%.

Also, I have inserted my battery til I heard the "click" but then noticed that BOTH sides were not fully locked. I now always check battery after attaching to be sure it's firmly in place.

Sounds like there were no wires or power lines over the lake. But the rear sensors would probably not detect either of those. I'm assuming you are certain that you could not have reached the other end of the lake? As you could have hit a tree, or other obstacle. Leafless trees are invisible to the sensors. I've been there. Did you check the map to be sure you were in the middle of the lake, not the other end?
NOPE... I had just taken off, and I JUST recharged that battery. I had EVERY bit of 22 minutes left.

NOPE... Battery locked fully in place, craft stayed level, flight was slow, NO wind, NO obstacles.

NOPE... NOT on end of lake... lake is HUGE, 6 miles long, 1 and 2 miles wide. I was not even a 1/4 mile, 200-300 meters away from craft standing in the OPEN VIEW. DIRECT line of sight with craft.
 
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