Mavic dropped mid air -> destroyed

[rocdok]

mine dropped over water May 21. It's in a separate thread 'lost in water can u read logs. I'm currently awaiting verdict from Dji. Where do i find the production date?

 

[Dyso_70]

Hello,

Today i was flying with my mavic, and suddenly, all motors stopped, and it drop from the sky (40m heigh). I was pushing both stick forward before it dropped. Battery was 79%, 12 gps, gps mode, 40 m height, 85m away and full in my sight. Just before it touched the ground, all the motors turned back on, but it was too late and now my mavic is completly destroyed. Can you tell me what happend ?

I had a similar problem about a month ago. I have sent my machine to DJI for data analysis. Waiting for the results.

 

[smh]

I think you probably activated both stick (see remote controller urgent stop mode)to emergency stop the motor ..

No, both stick were up !

 

[smh]

@smh , I've added your incident to my list of similar ones. It seemed like these power loss issues had pretty much gone away, but it looks like there is still an issue. Your Mavic was built a little more recently than the others on my list, which is a little worrying. Would you mind also trying to find the build date of the battery? It's one data point I hadn't started tracking at the beginning, but it could be worth noting.

One thing that seems to be unique about your incident is that you observed the motors start up again. Also, did I understand correctly that the front LEDs remained lit the whole time, even when the motors were stopped and the Mavic was falling? I've never heard anyone report that before, either.

BTW, here's the link to the data I'm collecting:

Mavic Power Failures - Airtable

I didnt notice if the front led were lit during the fall, but once on the ground, they were lit (back LED also). Maybe they light up again when the motors restarted.
Battery "birthday" : Wednesday, March, 15th 2017

 

[bemeis]

No, both stick were up !

Look at post 80, @mig25 said that if you push both sticks all the way up it could cause the mavic to go into over discharge protection and drop out of the sky

 

[smh]

Look at post 80, @mig25 said that if you push both sticks all the way up it could cause the mavic to go into over discharge protection and drop out of the sky

For me, this is unacceptable. Do you really think that I'm the only one who is doing that ? For sure every Mavic owner has at one time pushed both stick up at the same time. In my opinion, that's not a valid reason for a drone to fall out from the sky.
If it is, should'nt DJI warn about the risks ? Or at least, don't allow this move ?

 

[Derlisz]

Look at post 80, @mig25 said that if you push both sticks all the way up it could cause the mavic to go into over discharge protection and drop out of the sky

Sounds like nonsense to me. Who is this supposed to be protecting? Battery? By making it fall from the sky along with the rest of the drone. I have once seen a warning flying my p3a full stick up in the cold. Protection send the warning and slowed the drone significantly preventing it to crash due to discharge. If anything this would be a proof that it didn't kick in when it should have.

 

[tmw2023]

Look at post 80, @mig25 said that if you push both sticks all the way up it could cause the mavic to go into over discharge protection and drop out of the sky

A basic rule of any equipment is you shouldn't be able to damage it by using the front panel controls.

 

[BudWalker]

Do we know that "over discharge protection" means total battery shutdown? Or, that "over discharge protection" applies to currents seen in normal operations? I had a situation where Sport mode, full throttle resulted in a battery warning to be displayed in the Go App. The battery output was then limited, not cut off.

I've speculated that there may be safety circuitry that will cause a total shutdown in a situation where a battery fire or explosion is likely. E.g., the battery contacts are accidentally shorted. Maybe that's what is meant by "over discharge protection". A defect in that circuitry could then cause these total shutdowns.

 

[smh]

Do we know that "over discharge protection" means total battery shutdown? Or, that "over discharge protection" applies to currents seen in normal operations? I had a situation where Sport mode, full throttle resulted in a battery warning to be displayed in the Go App. The battery output was then limited, not cut off.

I've speculated that there may be safety circuitry that will cause a total shutdown in a situation where a battery fire or explosion is likely. E.g., the battery contacts are accidentally shorted. Maybe that's what is meant by "over discharge protection". A defect in that circuitry could then cause these total shutdowns.

But why the battery is still functionnal then ? If this is some hardware issue, shouldn't the battery be dead ?

 

[BudWalker]

But why the battery is still functionnal then ? If this is some hardware issue, shouldn't the battery be dead ?

I'm just speculating. I don't actually know. Maybe the overload detection circuitry is based on a temp sensor.

 

[vimagreg]

Waiting for news. Really scary story. Mine is coming in a very few days, first drone ever. Reading all I can about it.

 

[_milo_]

Waiting for news. Really scary story. Mine is coming in a very few days, first drone ever. Reading all I can about it.

The Mavic is really easy, basically flies itself, however I'd suggest buying inexpensive quadcopter, or at least some flight sim, so you have an idea how to fly if the Mavic went into Atti mode.

 

[odonnks]

Re the earlier posts about flying under bridges.
My P4 does this and it appears that the MP does too.

When flying under bridges or around large metal sheeting like wishing 2 ft of the metal roof on my home and garage the DJI Go app reports A Compass error.
According to DJI when this happens the quad switches from GPS to Atti mode which could explained why a earlier poster lost his in the water under a bridge.

 

[Kestrel]

No Usually the Overcurrent Discharge doesn't make the Mavic fall out of the sky, some people experienced Over-current discharge by using sport mode, none to my knowledge fell out of the sky, I actually experienced Overcurrent Discharge before and no my Mavic didn't fall from the sky.

 

[mig25]

Do we know that "over discharge protection" means total battery shutdown? Or, that "over discharge protection" applies to currents seen in normal operations? I had a situation where Sport mode, full throttle resulted in a battery warning to be displayed in the Go App. The battery output was then limited, not cut off.

I've speculated that there may be safety circuitry that will cause a total shutdown in a situation where a battery fire or explosion is likely. E.g., the battery contacts are accidentally shorted. Maybe that's what is meant by "over discharge protection". A defect in that circuitry could then cause these total shutdowns.

They have two
Check out 7-8
Mavic Pro User Manual DJI Intelligent Flight Battery Functions1. Battery Level Display: The LED indicators display the current battery level.2. Auto-Discharging Function: To prevent swelling, the battery automatically discharges to below 65% oftotal power when it is idle for more than ten days. It takes around two days to discharge the battery to 65%. It is normal to feel moderate heat being emitted from the battery during the discharge process. Discharge thresholds can be set in the DJI GO 4 app.3. Balanced Charging: Automatically balances the voltage of each battery cell when charging.4. Overcharge Protection: Charging automatically stops when the battery is fully charged.5. Temperature Detection: The battery will only charge when the temperature is between 5°C (41°F) and40°C (104°F).6. Over Current Protection: The battery stops charging when a high amperage (more than 8.5A) isdetected.7. Over Discharge Protection: To prevent over-discharge damage, discharging automatically stops.8. Short Circuit Protection: Automatically cuts the power supply when a short circuit is detected.9. Battery Cell Damage Protection: The DJI GO 4 app displays a warning message when a damagedbattery cell is detected.10. Sleep Mode: To save power, the battery will cut off power supply and enter sleep mode after 20minutes of inactivity.11. Communication: Information pertaining to the battery’s voltage, capacity, current, etc. is transmitted tothe aircraft’s main controller.Refer to Mavic Pro Intelligent Flight Battery Safety Guidelines before use. Users take full responsibility for all operations and usage. Using the Battery

 

[yokota85]

I am seeing a bunch of posts on several forms of the same thing, drones dropping out of the sky, I am at the point I am not sure they are safe to fly anymore

 

[audioguy]

I have yet to fly my Mavic and it is stories like these that really frighten me. As it is, my bride thinks I'm nuts. If a crash that were to happen to me, I would never hear the end of it !!!

 

[WaveJunkie]

I have yet to fly my Mavic and it is stories like these that really frighten me. As it is, my bride thinks I'm nuts. If a crash that were to happen to me, I would never hear the end of it !!!

I am seeing a bunch of posts on several forms of the same thing, drones dropping out of the sky, I am at the point I am not sure they are safe to fly anymore

As a new Mavic owner myself, I've been in a few scary situations So I can relate to your initial feelings. It seems that the flight algorithms, safety systems and e-systems are just not perfect yet. However the Mavic seems to be the best "drone" in the market from what I have seen.

My mind was blown on how rock steady the Mavic was flying for the first time, Zero drift! That is also what gives me the willies... If I see it drift. It seems like every couple of flights (3-4) I will have weird drifting like gps drift... over a couple of feet usually in a specific direction but ignoring the visual positioning?

The auto-land / RTH have been terrifying, with them only working properly the last two flights (after .700 update) (& Yes home point was set). After activating RTH I have had it take off in another direction at high speed, would not cancel and having to fight it to land (holding directional stick in opposite direction of travel at max just to maintain rough position to land).

I try now to make it a habit before every flight to check everything, no metal around & calibrate all the sensors. Have not crashed or maimed anyone since.

Don't be discouraged, Whether it is a $1000 Mavic or $30 copter... stuff happens so you just need to be on the ball !!

For me all is good and my mind at ease when seeing that crisp 1080p birdseye view of life.

 

[dewster]

Couple of questions:

Is it possible for the battery to have a sag in power under extreme demands and cause a temporary power loss?

Can the Mavic stay airborne if one of the pins on the battery are damaged or not have a solid connection with the craft?