Strange behavior of the mavic mini

[Arted]

Hello everyone
I’m enjoying my mavic mini, and exept the motor error speed error which hasn’t happened anymore since i put it carefully in the case i noticed a strage behavior twice
1) i was flying in low altitude and i was trying to get a some quick shots , after finishing, i directed the drone in a small lake, the drone was hovering on the lake almost 3-5 m from the water level , and i noticed the drone going down towards the water, so i pulled it up immediately , the wind was blowing at 4-5 miles , with gusts 11 mph
I thought it was something normal
2) yesterday , after taking some quick shots in a basketball field, i was checking the area while the drone was hovering at 1.5 m in position , when i turned and saw the drone , i noticed it was trying to land, like it was loosing altitude , the same thing that happened in the lake, so i jsut pulled it again up
Has anyone gad the same problem?
the props work normaly,gps signal is perfect, the compass has been calibrated , but the drone decides to land himself
Thank you

 

[SMLP]

I would be interested in other people's thoughts about this. I did a bit of digging around after I first had the "Motor Error Speed" message (Post Here) and your correct it basically the way the bird is put in its box. This issue i have not had... but if one person is having it then my guess is more people are having the same issue. I'll keep an eye out for this and let you know if I have the same problem (once the wind chills out).

 

[slup]

Yeah, we have seen loads of uncommanded descents with the Mini since the beginning of this year ... on the latest firmware DJI have incorporated a ESC beep together with a message in the Fly app about replacing props after a flight if some of them have been deformed.

Attach the .TXT log from a flight when this happens so can we possibly see the cause ... read up here on how to retrieve the log --> Mavic Flight Log Retrieval and Analysis Guide (read under section 3.)

 

[Zbip57]

[...] the motor error speed error which hasn’t happened anymore since i put it carefully in the case [...]

Did you replace the propeller blades on the motor indicated in the motor speed error message?

 

[SMLP]

Did you replace the propeller blades on the motor indicated in the motor speed error message?

Yes almost immediately (both of them with a matching set) done another 6 flights since then without issue... only thing I have changed (other than the props) is the way I store in the fly more case.

 

[Zbip57]

I was asking Arted, who posted the first message in this thread. From his description it sounds like he got the Motor Speed warning once, but hasn't received the message again since storing the Mini carefully in its flymore case. It isn't clear whether he actually replaced the props.

Posting the DAT logfile would help us analyze what's going on.

 

[Zbip57]

only thing I have changed (other than the props) is the way I store in the fly more case.

I received the Motor Speed warning on my first flight after updating to the v01.0.0500 firmware and replaced the offending prop blades. There has been no repeat of the warning since then.

As you described in your blog post, some people suggest downgrading to the previous firmware version to make the warning go away. That seems pretty stupid, considering that DJI mut have had a reason for adding the warning. The other stupidity is the suggestion to check the blades for any visible defect and, if they look okay, just keep flying.

I replaced the left rear prop blades as instructed by the warning message. There didn't appear to be anything visibly wrong with the blades. Never crashed. No knicks or cracks. Always stored properly in the fly more case.

But, upon installing the fresh props I now do see a noticeable difference. See photo and compare the tip height of the new left blades versus the still original right blades. The left rear blades used to slide easily to nest under/over the right rear blades, but not any more. The tips of either the right or left blades would now need to be bent down to force the blades to mesh when folded together. (Sorry I don't have a photo of the original set).

I now suspect that the problem isn't just improper storage in the case (although that would certainly also be bad). I think the prop deformation problem may be a result of repeatedly forcing the blades to nest under/over each other whenever the arms are folded.

 

[Capt KO]

Flying (especially hovering) low over water, will cause the Mini to descend, even with everything in perfect order. It’s a know issue that effects other drones as well, but worse with the Mini. Keep it in sight visually, not just watching your screen, to avoid water landings. Staying above 20 ft. is usually safe. Always watch the altimeter for movement, when hovering over water. All from personal experience, it happens to me often.

Uncommanded descent, over land or water, is a totally different problem with props and rear motors. More about that in different threads.

I recommend Care Refresh and a retrieval float. Have fun. ?

 

[Arted]

Did you replace the propeller blades on the motor indicated in the motor speed error message?

no , I didn’t change the props, as the drone was just bought, and it was the 2day . I figured out it was the way the drone was staying in the case ,
I refreshed the drone again with the dji assistant , and One battery needed an update , since that day no motr speed error anymore,

 

[Arted]

Flying (especially hovering) low over water, will cause the Mini to descend, even with everything in perfect order. It’s a know issue that effects other drones as well, but worse with the Mini. Keep it in sight visually, not just watching your screen, to avoid water landings. Staying above 20 ft. is usually safe. Always watch the altimeter for movement, when hovering over water. All from personal experience, it happens to me often.

Uncommanded descent, over land or water, is a totally different problem with props and rear motors. More about that in different threads.

I recommend Care Refresh and a retrieval float. Have fun. ?

The drone was no more than 10 m away from me , and u never fly out of visual sight, ok , maybe it happens in water, but the second time it happened in the basketball field, probably the color if the field was “ tricking” the sensor ?

 

[Zbip57]

no , I didn’t change the props, as the drone was just bought, and it was the 2day.

I suggest you read all of this thread:

Mavic Mini uncommanded descent tests

After a little experimentation I was able to replicate the uncommanded descent problem under 0400 firmware by loading the rear props for a few hours as might happen in the flymore case. The props did appear slightly flattened compared to the front props. The problem quickly manifested itself in...

mavicpilots.com

 

[HWCM]

This is not the issue he is having.

Flying (especially hovering) low over water, will cause the Mini to descend, even with everything in perfect order. It’s a know issue that effects other drones as well, but worse with the Mini. Keep it in sight visually, not just watching your screen, to avoid water landings. Staying above 20 ft. is usually safe. Always watch the altimeter for movement, when hovering over water. All from personal experience, it happens to me often.

Uncommanded descent, over land or water, is a totally different problem with props and rear motors. More about that in different threads.

I recommend Care Refresh and a retrieval float. Have fun. [emoji41]

 

[HWCM]

No. You need to change your props.
I ignored the messages too because they did not come up on flights after.
The next time I flew, I was about a mile away and it would not maintain altitude or fly forward. Luckily by mistake, I noticed it would ascend when flying in reverse. After posting my issue here with the flight logs, it was confirmed to be the props. They looked fine, like new. But once they were off the mini and I compared them to the new props, I could see that they were almost flat toward the tip. I think it's from the fly more case. Because I had a case from Amazon that I had been using that is soft foam and I have stored the mini in it for weeks at a time. I bought a fly more case and the mini was in it for about a week, my next flight I had the issues. Doing some testing, I can see that the mini rests on the props while in the fly more case. I added some 3mm thick foam to raise the mini up off the props while in the case.
New props fixed the flight issue. I flew three batteries today, no issues. Full stick in sport mode three miles out and back.
She the pictures below.

The drone was no more than 10 m away from me , and u never fly out of visual sight, ok , maybe it happens in water, but the second time it happened in the basketball field, probably the color if the field was “ tricking” the sensor ?

 

[Capt KO]

This is not the issue he is having.

*Yes it might. Descending while hovering over water, without input (sensors). If it happens in other locations, probably props (uncommanded decent). He needs to know All possibilities, it’s a Mini! They’re different but can be a good bird if educated about known flaws.
*Yes, the sensor problem happens Low over any solid color surface. Ball court, grass, ice, snow, water, etc.

*HWCM, good explanation of the prop problems. ?