Mavic Mini wrecked. Will DJI replace?

[cameraz]

Is DJI likely to repair my damaged Mavic Mini under Care Refresh which I have? Their plan says service does not cover, (among other things): “Damage caused by flight in unsuitable environments.”

Here’s what happened. When I first started flying, a message came on my screen saying, “Aircraft in Altitude Zone (Altitude Limit 492 ft). Fly with caution.” I wasn’t planning to go anywhere near that high. Note: All my flying was in Cine Mode (C).

While reaching a height of 137.7 ft., I received a “Strong Wind Warning.” So I descended to 39.3 ft and flew back to where I was standing. I went back up to 52 ft. and received the Altitude Zone warning again.

I then flew 90 degrees to the left of where I had been flying at a height of 8.5 ft. I soon received a message saying, “Lighting environment too dark. Visual positioning inaccurate. Fly with caution.”

I soon found the drone heading straight for a small tree, and immediately pulled the right stick into reverse. The drone seemed to clear all of the branches. But then a very quick “Compass Calibration Required” flashed on the screen, although right before taking off I did calibrate the compass.

All of the sudden (with neither of my thumbs on the controls), the drone shoots 90 degrees across the street at what looked like 2 to 3 times the speed it was set on (C) and apparently bounced in the middle of a parking lot. The altitude when this happened was listed at -21.6 ft. It then took off again at high speed and continued across the street, smashing into a building at -24.6 ft.

What I’d like to know is, how can the altitude be measured as negative?

Meanwhile, I plan to send the drone back to DJI for replacment, but what are the chances they’ll say I was flying in “unsuitable environments?”

 

[Starz]

Based on your description, i would think it’s on your dime.
I’ve been wrong several times and could be on this one also.

 

[cameraz]

Except that in the last minute where I was flying with no problems, the drone suddenly veered 90 degrees at a high speed -- completely without input from me -- and crashed into a building.

Let's say you're flying over a lake for 10 minutes, and during that time you receive several warning messages. You then make the drone return home, and two feet before it lands (on dry land), it suddenly veers off 90 degrees and crashes into the lake. This happens with no input on the control sticks from the operator. Is that the operator's fault?

 

[ckoerner]

There’s some wizards on the forums who might be able to help determine the cause of the crash if you share the flight logs. Just to temper expectations, there’s no promises anyone can help and a large majority of the time it’s pilot error.

 

[Meta4]

Meanwhile, I plan to send the drone back to DJI for replacment, but what are the chances they’ll say I was flying in “unsuitable environments?”

Post your flight data.
It will show what happened a lot better than you can explain.

Go to DJI Flight Log Viewer | Phantom Help
Follow the instructions there to upload your flight record from your phone or tablet.
That will give you a report of the flight.
Come back and post a link to the report it gives you, even if it looks empty.
Or .. just post the txt file here.

What I’d like to know is, how can the altitude be measured as negative?

It could be normal, the altitude shown by the barometric sensor commonly varies over the time of a flight or you might have flown below the level of the launch point..
Or it could be a result of impact on the IMU in a crash.
The data will make it clear what the explanation is.

 

[cameraz]

OK, here is a copy of my Flight Record .txt file. I'm not sure if I'm doing this right because the text is not readable to me.
If I need to, tomorrow I will install a log viewer app on my phone and try again.

 

[cameraz]

I may or may not have this figured out. Here is a link to my Flight Record (I think):

DJI Flight Record 03/25/21

 

[Meta4]

I then flew 90 degrees to the left of where I had been flying at a height of 8.5 ft. I soon received a message saying, “Lighting environment too dark. Visual positioning inaccurate. Fly with caution.”

I soon found the drone heading straight for a small tree, and immediately pulled the right stick into reverse. The drone seemed to clear all of the branches. But then a very quick “Compass Calibration Required” flashed on the screen, although right before taking off I did calibrate the compass.

All of the sudden (with neither of my thumbs on the controls), the drone shoots 90 degrees across the street at what looked like 2 to 3 times the speed it was set on (C) and apparently bounced in the middle of a parking lot. The altitude when this happened was listed at -21.6 ft. It then took off again at high speed and continued across the street, smashing into a building at -24.6 ft.

Here's the story that the data is telling.
You did a lot of slow flying in Tripod Mode around a tall building and things went fine until shortly after you got the message at 11:12.9.
The message said:
Lighting environment too dark. Visual positioning inaccurate. Fly with caution.
That was not a problem, it was just advising that conditions were tood ark for the VPS sensors to give horizontal position holding if required.

Shortly after you went closer to the building which blocked out a lot of the sky (and satellites) and at 11:19.3 you lost GPS position holding because so many sats had been lost.
From here on, the drone had no GPS or VPS horizontal position holding ability and was effectively in Atti Mode.
That means it had no brakes and would continue drifting if you went hands-off with the joysticks.

At 11:21.7 the pitch and roll data indicates that the drone hit something and probably damaged a propeller because it started to lose height as it spun anti-clockwise quite quickly.
VPS data shows the drone at about 12 ft above something but the screen display of your height was showing negative numbers.
If the drone was not lower than your starting point, this is due to the initial impact.
It looks like there was a second collision about 4 seconds later which accounts for the drone jumping up briefly before falling further.

What I’d like to know is, how can the altitude be measured as negative?

Did the drone end up lower than the launch position, or was it at around the same level?

what are the chances they’ll say I was flying in “unsuitable environments?”

DJI are likely to suggest that flying in a GPS-denied environment while close to obstacles is an unsuitable environment.
The drone was still controllable, but flying without GPS and without brakes requires practice and gentle stick movements.
You weren't used to flying in atti mode and pulled the right stick lull back.
When you released the sticks, the drone didn't stop and kept going into the tree.

Sometimes DJI make mistakes and a week back another flyer managed to have a win where he was flying recklessly in a similar situation and DJI gave him a replacement, despite what looked like blatant operator error..
I wouldn't count on them making the same mistake but you never know what they'll do.

 

[cameraz]

Thank you for your accurate assessment. I don't have much experience flying in Atti mode so thought that my evasive maneuver got me out of trouble. Also, I launched the drone from my hand up in the air, so that must explain the negative altitude readings.

Live and learn. I will send the Mavic Mini back to DJI and see what they say. Like you said, you never know what they'll do.

 

[Repaid1]

Is DJI likely to repair my damaged Mavic Mini under Care Refresh which I have? Their plan says service does not cover, (among other things): “Damage caused by flight in unsuitable environments.”

Here’s what happened. When I first started flying, a message came on my screen saying, “Aircraft in Altitude Zone (Altitude Limit 492 ft). Fly with caution.” I wasn’t planning to go anywhere near that high. Note: All my flying was in Cine Mode (C).

While reaching a height of 137.7 ft., I received a “Strong Wind Warning.” So I descended to 39.3 ft and flew back to where I was standing. I went back up to 52 ft. and received the Altitude Zone warning again.

I then flew 90 degrees to the left of where I had been flying at a height of 8.5 ft. I soon received a message saying, “Lighting environment too dark. Visual positioning inaccurate. Fly with caution.”

I soon found the drone heading straight for a small tree, and immediately pulled the right stick into reverse. The drone seemed to clear all of the branches. But then a very quick “Compass Calibration Required” flashed on the screen, although right before taking off I did calibrate the compass.

All of the sudden (with neither of my thumbs on the controls), the drone shoots 90 degrees across the street at what looked like 2 to 3 times the speed it was set on (C) and apparently bounced in the middle of a parking lot. The altitude when this happened was listed at -21.6 ft. It then took off again at high speed and continued across the street, smashing into a building at -24.6 ft.

What I’d like to know is, how can the altitude be measured as negative?

Meanwhile, I plan to send the drone back to DJI for replacment, but what are the chances they’ll say I was flying in “unsuitable environments?”

I will chime in and say that it was operator error from above, and that indeed is covered under care refresh given what you did on flight and you because of error caused the collison, that is exactly what the Care Refresh program is for. I personally think they will cover it under your refresh plan...IMHO. But ehhh.... like above have been wrong.

You should let DJI handle all shipping though, so if not sent, let them do all the leg work and tracking.

 

[G Saunders]

FWIW, my experience with CareRefresh is that I've sent a drone with a CareRefresh policy in and say I crashed it and it was no fault of the drone, they'll send out a replacement the next day after they receive it.

On the two occasions where I questioned whether the drone was at fault, it apparently took a couple days to get a specialist's attention. Once, in what I suspect was a smashed Mini prop that was probably my fault, they agreed and sent a replacement under warranty. The other time, where I questioned the drone but wasn't sure, they called it user error, dinged the CareRefresh policy and sent the replacement.

When you start the repair request, they'll send a shipping label for the return. All my experience with DJI has been the best, something like six or seven replacements, from Minis through Inspires...

 

[cameraz]

Though you guys would like to see a short video of my ill-fated flight last week.

It Wasn't Supposed to Happen LIke This

 

[Flyhighsky]

Though you guys would like to see a short video of my ill-fated flight last week.

It Wasn't Supposed to Happen LIke This

awwww...ouch that hurt

 

[cameraz]

It took UPS five (5) days to finally email me a free shipping label. I'm sure it will take them longer than that to deliver my MM to DJI in Texas (ground delivery). I dropped my drone off at the UPS store yesterday ... I'll let you all know how it goes.

 

[cowandchicken86]

Out of curiosity, how does the drone tell if the wind is too strong ? It has no sensors for that ? I've had the notification in a windy condition but the drone hovered fine and wasn't drifting

 

[DJayI]

Out of curiosity, how does the drone tell if the wind is too strong ? It has no sensors for that ? I've had the notification in a windy condition but the drone hovered fine and wasn't drifting

It probably uses the pitch, roll, and yaw sensors combined with the amount of power it has to send to the motors to attempt to overcome the disturbance. For instance, high headwind, so it has to tilt to an extreme forward angle and max the throttle to compensate. When it is close to being unable to compensate, probably throws the warning.
Just a guess.

 

[gunja99]

Ouch... Out of interest, did you hit the lamp when reversing out the tree? Seems might have. I've only got a few hours flight time under my belt, but I've already had a few close calls with branches and wires, etc. It's very easy to hit soemthing esp in reverse!

 

[cameraz]

Ouch... Out of interest, did you hit the lamp when reversing out the tree? Seems might have. I've only got a few hours flight time under my belt, but I've already had a few close calls with branches and wires, etc. It's very easy to hit soemthing esp in reverse!

Yes, I think I did hit the lamp post, and broke a propeller or two ... which sent my Mini careening 90 degrees to the right. I did not have visual line of sight, and was flying by what was on my screen. Also, my Mini had lost its GPS connection, and was in Atti mode. After backing away from the tree, I took both thumbs off my control sticks so I could figure out what to do next. But being in Atti, you have no auto-braking, so the drone just continued into the lamp post.

Live and learn!

 

[cameraz]

FWIW, my experience with CareRefresh is that I've sent a drone with a CareRefresh policy in and say I crashed it and it was no fault of the drone, they'll send out a replacement the next day after they receive it.

On the two occasions where I questioned whether the drone was at fault, it apparently took a couple days to get a specialist's attention. Once, in what I suspect was a smashed Mini prop that was probably my fault, they agreed and sent a replacement under warranty. The other time, where I questioned the drone but wasn't sure, they called it user error, dinged the CareRefresh policy and sent the replacement.

When you start the repair request, they'll send a shipping label for the return. All my experience with DJI has been the best, something like six or seven replacements, from Minis through Inspires...

When DJI sent you a replacement drone, did you have to pay a fee for it (aside of what you initially paid when you purchased the Care Refresh plan)?

 

[Gagey52]

awwww...ouch that hurt

That would make you cry
Regards