I was flying in P mode about 2 feet above ice and snow on a river about 10 miles and hour. My Mavic 2 Zoom started to fly lower by itself till it crashed in about 50 feet. There was no damage on the outside of the unit. But the zoom feature stopped working and it wouldnt update the internal software. I had to send it in to DJI. They told me that the main board was bad and the camera module was bad. This would cost $532. DJI sent me a brand new unit. DJI was very prompt about everthing. I am just dismayed at how much this cost and why did it fly lower by itself. DJI told me the sensors don't pick up ice and snow. That's fine. But I was flying on a perfectly level river. Oh well, live and learn. If you want to see the video you can see it here.

Ouch. At least you got a replacement and didn't have to pay.

Why were you flying two feet above the ice? I'm just curious.

Woe Posted at 1-31 07:23
Ouch. At least you got a replacement and didn't have to pay.

I had to pay$532.

jyc Posted at 1-31 07:38
Why were you flying two feet above the ice? I'm just curious.

Getting cool video and then flying higher continuing the video. There was a car and a dog that came out on the ice as I was flying. So I was being distracted. But still no reason why it just descended on it's own.

NathanN Posted at 1-31 08:00
Getting cool video and then flying higher continuing the video. There was a car and a dog that came out on the ice as I was flying. So I was being distracted. But still no reason why it just descended on it's own.

I believe flying that close to the smooth/reflective surface messes with the downward vision position sensors........

Could you still controle the drone? TapFly mode?

TrippleDelta Posted at 1-31 08:13
Could you still controle the drone? TapFly mode?

I was flying in complete manual P mode at the time. I wasn't watching screen at the moment because a car came out on the ice and released their dog which was running circles around me. I looked down the screen in time to see it crash.  So if I had not been distracted I would have been rising higher.

Post the flight log. Maybe you pressed the down stick.

NathanN Posted at 1-31 07:57
I had to pay$532.

Ouch. I read that wrong.

ghostrdr Posted at 1-31 08:22
Post the flight log. Maybe you pressed the down stick.

I did send the flight logs to DJI. Here is what they said.  
1. The unit was in P-GPS mode and was responsive to RC input.  
2. The unit recorded external impact, at flight time: 04:28
3. User commanded full pitch forward and crashed onto the ground
4. Unit obstacle avoidance cannot  detect ice or snow
Incident date: 2019 01 05
Incident GPS location:  45.079089 -92.787616

According to the analysis, the incident was not caused by any product malfunction.

Damn shame, but?  No fun that's for sure, and with yapping dog at your heels as well.

NathanN Posted at 1-31 07:57
I had to pay$532.

In order to figure out what happened you would need to post your flight log, DJI would have given you an explanation as to what happened so maybe the answer is there or in your flight log .
Edit I see you post on djis report apologies .

Full tilt forward with sensors not working at 2ft is pretty risky so it looks like this one is pretty simple.

I always disable sensors when I fly  low over reflective surface.
Best to watch your drone yourself and not let the tech do the job.
DJI is 100% clear about this in the manual btw. Sensors get fooled by reflective surfaces.
Lesson learned the hard way unfortunately.

I don't have a Mavic 2 Zoom, but both my Air and Phantom experience altimeter (barometer) inaccuracies over the course of the flight. Since it works off the barometer, changing conditions can throw off the altitude a bit (it's been suggested that the heat from the drone itself can throw it off a little).  My first phantom would sometimes end up 40 feet of altitude off  after a 15 minute flight (I exchanged it for  a e second that was a little better) For this reason, I never trust it to hold an exact altitude.  Normally, the vision sensors would keep it from crashing if it could detect the ground, but as noted, they don't always work over ice/water.  

In other words - if a tiny bit of altitude change is important in your situation, please pay close attention to what the bird is doing.

I knew that DJI sensors have problems when low over water (not just the Mavic either)..  But I don't recall them saying anything about ice/snow.   I thought you might have a point of contention so  I double checked the Mavic 2 user manual.  Sure enough on Page 22 it says "The vision system may NOT function properly when the aircraft is flying over water or snow covered areas".   So much for that.

Glad you're back in the air.....
  

I wouldn’t  have paid for repairs... doesn’t makes sense the aircraft was otherwise functional but couldn’t sync to computer and zoom wasn’t working.. 10mph crash isn’t that bad.. I nailed my mavic air at 40+ mph into a solid object and only broke the antenna nearly the gimbal.... probably only needed minor work done to the camera...probably needed a new ribbon cables maybe messed up, or for the plugs I gotten reseated which shouldn’t cost much.   

looks like corruption is still afoot in DJI.. overcharging for basic level repairs..  may not been able to sync to computer cuz drivers problematic, usb cable was bad, maybe USB port wasn’t ready for some reason, or maybe if camera unplugged it can’t start syncing and is an oversight during testing by DJI..

NathanN Posted at 1-31 08:46
I did send the flight logs to DJI. Here is what they said.  
1. The unit was in P-GPS mode and was responsive to RC input.  
2. The unit recorded external impact, at flight time: 04:28

Yeah, flying full pitch forward will cause a decrease in altitude and you lacked a suitable surface for which the downward sensors could warn and compensate. Sorry bout that!

I would fly twice as high and use zoom to make it look closer. Sux loosing bird.

I was going to say you are lucky that you could get out on the thick ice to retrieve it but since you did not have the Care package, I guess it still cost a bundle for a replacement.

Glad that you got a replacement one, be careful next time

Oof. That aint good. This is the reason why I have trust issues with the height readout in DJI go as it said I was approximately 12-15 feet off the waves at this beach when in reality it was about 5 feet. I guess this could be due to optical systems being used instead of LIDAR/SONAR like the Mavic 1 had.

All is well that end's well.

I guess you can flight from some reasonable height will zooming, that will create the close ground feeling effect.

After a few crashes, I've decided 15 feet is the closest I will go to anything with a mavic 2 zoom.  Anything else is risky, so be prepared for a possible crash.

Dang ... Hard landing

Full stick forward is pretty risky at 2'. The drone at that angle naturally wants to lose altitude, not much room for error ;)

Here is just a dumb question, you didn't you notice the ice coming closer and closer in your field of view? I don't know about you all but I fly by looking at the screen on my Mini or Note 8 and I know I can see the ground coming closer when doing low altitude stuff, or if I know it's a very precise area to fly in i'll watch the bird itself on not the Screen.

Strobing_NYC Posted at 2-10 16:17
Here is just a dumb question, you didn't you notice the ice coming closer and closer in your field of view? I don't know about you all but I fly by looking at the screen on my Mini or Note 8 and I know I can see the ground coming closer when doing low altitude stuff, or if I know it's a very precise area to fly in i'll watch the bird itself on not the Screen.

I was flying in complete manual P mode at the time. I wasn't watching screen at the moment because a car came out on the ice and released their dog which was running circles around me. I looked down the screen in time to see it crash.  So if I had not been distracted I would have been rising higher.

STUFF2C Posted at 2-10 15:24
Full stick forward is pretty risky at 2'. The drone at that angle naturally wants to lose altitude, not much room for error ;)

DJI says according to flight log that I was full stick forward. I don't believe I was because that would have been 30 miles and hour. When I hit the snow covered ice it flipped and came to a stop. There is no way that at 30 miles and hour it would have stopped that quickly. If that dog had not been running circles around me I would have been going higher.