So, I was having a good day and decided to fly my Mini 2 indoors for a bit. (I have done this many times before with no problem.). So, I started the motors, with no issue but as soon as there is a little bit of thrust, the drone goes haywire. The Mini 2 flies full speed into the wall, breaking 2 more propellers, the battery door, and the gimbal yaw arm. I have since replaced the props and it flies fine but after some forensic tests, I have come to the conclusion that the propeller broke off after takeoff. The 2 front propellers were matched up with what remained of the propeller hubs but the rear left motor was missing one prop, but the base was still there. I searched around for 30 mins around my foyer with no luck in finding it. I will post some pictures tomorrow as it is getting late. But I have the security camera footage of the drone smashing itself into the wall. As you can see in the footage, the only stick input is throttle up, immediately followed by throttle down in an effort to save the drone. In addition to that, I did a preflight check finding no damage on the propellers. The Crash Video I have Care Refresh but I don't want to use one of my 2 replacements on an issue that I don't think I even caused.
UPDATE: I am sending it for diagnosis. Let's see what happened.

If you share the flight log of you flight, some people smarter than myself will have a look.
https://www.phantomhelp.com/LogViewer/upload/

Great post.  I can confirm you crashed your drone.

Hi, IRMMZ 1. Thank you for reaching out and we're deeply sorry for the incident that happened. In this kind of situation, I'm afraid that you may consider sending the unit in for a proper diagnosis.  You may submit an online repair request through this link: {https://repair.dji.com/repair/index}. If you need assistance with creating a ticket, you may contact DJI support at https://www.dji.com/support. We understand that this is not the answer that you look forward to, but this would be the best thing to do in this situation. In addition, warranty service can be claimed depending on the result of the Damage Assessment. Your kind understanding is appreciated and thank you for your continued support.

Drone broke itself?  lol.  Really looking forward to a log file upload.

Dirty Bird Posted at 12-27 05:53
He won't be able to grab the log like normal as there was no phone attached to the controller.  The on-board flight log is there but only DJI can unencrypt & view that one.

Oh, that is a bummer.

Dirty Bird Posted at 12-27 05:53
He won't be able to grab the log like normal as there was no phone attached to the controller.  The on-board flight log is there but only DJI can unencrypt & view that one.

Well spotted !

Good spot!

TonyPHX Posted at 12-27 02:17
Drone broke itself?  lol.  Really looking forward to a log file upload.

If you look at my hands in the video, I didn't do anything other than throttle up and throttle down after starting the motors.

Did the drone fly in a straight line into the wall?

Sean-bumble-bee Posted at 12-27 10:38
Did the drone fly in a straight line into the wall?

Yes, it flew straight into the wall but it was vibrating a whole lot

IRMMZ 1 Posted at 12-27 11:16
Yes, it flew straight into the wall but it was vibrating a whole lot

Ah shaking does suggest a possible blade loss, could you get a good quality photo of the surface of the break in the remains of the missing rear prop?
In some metals the surface can show marks that are a characteristic of the faliure mechanism.
I do not know of plastics show the same thing but if there is a practising Mechanical Engineer on here they might recognise any that can be seen.
Do the broken front props all have signs of impact damage as well as breaks?

I am curious, if it flew forwards straight into the wall how did it managed to break the battery door?
Can you post a photo of the gimbal's broken yaw arm?

It's a pity the drone DAT's are unreadable, they probably contain motor speeds and with a missing prop a motor would be turning MUCH faster than the others to provide the necessary lift.

Sean-bumble-bee Posted at 12-27 11:38
Ah shaking does suggest a possible blade loss, could you get a good quality photo of the surface of the break in the remains of the missing rear prop?
In some metals the surface can show marks that are a characteristic of the faliure mechanism.
I do not know of plastics show the same thing but if there is a practising Mechanical Engineer on here they might recognise any that can be seen.

The battery door fractured because it landed on the floor on its back

Sean-bumble-bee Posted at 12-27 11:38
Ah shaking does suggest a possible blade loss, could you get a good quality photo of the surface of the break in the remains of the missing rear prop?
In some metals the surface can show marks that are a characteristic of the faliure mechanism.
I do not know of plastics show the same thing but if there is a practising Mechanical Engineer on here they might recognise any that can be seen.

Check the original message for the photos

IRMMZ 1 Posted at 12-27 11:16
Yes, it flew straight into the wall but it was vibrating a whole lot

That sounds like a propeller/motor issue.
Alwys check the blades before taking off.

Did it fly sort of like this one? ;)

Yaros1 Posted at 12-27 12:08
That sounds like a propeller/motor issue.
Alwys check the blades before taking off.

I always do a preflight check, this time I still found no damage. Then the drones propeller broke off on takeoff and flew into the wall.

IRMMZ 1 Posted at 12-27 12:13
I always do a preflight check, this time I still found no damage. Then the drones propeller broke off on takeoff and flew into the wall.

This could also have happened due to a VPS issue. The mini 2 doesn't have full VPS sensors as my Air 2 does, but it still uses downward facing sensors to stabilize itself in environments where GPS isn't available, such as when flying indoors. If these sensors fail for any reason (moving object below drone, insufficient lighting, etc...) it might destabilize the drone and cause a crash. Something similar happened to a friend of mine recently with an Air 1 when he was flying his drone in the forest with weak GPS, the visual positioning system failed and the drone drifted into a tree.

So what to take from this? I wouldn't recommend flying a Mini series drone without GPS, because they don't have the downward facing cameras to lock onto a pattern like the more expensive models do, and that makes them more unstable indoors, especially if there is some wind, low light conditions, or something moving underneath the drone.

Sadly you weren't connected to a mobile device during the crash so it's not possible to get and review the unencrypted log.
Send it to DJI for repair.

Ssayer Posted at 12-27 12:09
Did it fly sort of like this one? ;)

I hope the little girl got a replacement from Santa, I am delighted she didn't try to rescue it.
Brings back the old mantra FIREGUARD FIREGUARD.

Messing with an open fire was worth some harsh words or a spanked arse when I was a kid.

Dirty Bird Posted at 12-27 12:19
I watched the video many times frame by frame.   It isn't super clear, but I have to tell you when you first lift off it looks like your thumb is pressing forward a bit on the right stick & then you pull back as it lurches forward.  Indoors, with no GPS, it's going to drift until the VPS finds something to lock on.  A hardwood floor doesn't provide a lot of reference for stable hovering.  It is unfortunate you did not have a phone attached, though DJI can access the onboard flight logs if you send her in for repair.

I've never been a big fan of flying indoors.  Sure the Mini is tiny, but twice I had hairy experiences flying indoors.  Both times it was a similar situation.  Phantom 2 Vision+.  Took off on the bed.  Propwash caused the blanket to entangle the props.  That time it just got smothered in the bed.  No harm, no foul.  

I have already come to the conclusion that it was not a VPS issue, but the propeller breaking off at takeoff. A little after the drone's motors started, the drone can be seen vibrating on the floor, then taking off. I may have given a bit of correction by instinct but IDK. Then when the drone lifted off, the rear left motor, the one I suspected to have no propeller was vibrating a lot and causing the whole drone to vibrate like crazy. Also, if it was VPS, why would the drone go at such an angle at the wall? And why would it vibrate on takeoff?

Yaros1 Posted at 12-27 12:20
This could also have happened due to a VPS issue. The mini 2 doesn't have full VPS sensors as my Air 2 does, but it still uses downward facing sensors to stabilize itself in environments where GPS isn't available, such as when flying indoors. If these sensors fail for any reason (moving object below drone, insufficient lighting, etc...) it might destabilize the drone and cause a crash. Something similar happened to a friend of mine recently with an Air 1 when he was flying his drone in the forest with weak GPS, the visual positioning system failed and the drone drifted into a tree.

So what to take from this? I wouldn't recommend flying a Mini series drone without GPS, because they don't have the downward facing cameras to lock onto a pattern like the more expensive models do, and that makes them more unstable indoors, especially if there is some wind, low light conditions, or something moving underneath the drone.

I have also flown my phantom 2, mavic pro, and phantom 3 pro indoors with no problem. None of them ever crashed because I was very careful of all the factors. But this is NOT VPS for sure.

Ssayer Posted at 12-27 12:09
Did it fly sort of like this one? ;)

https://vimeo.com/784624142

LMAO, this clip got me wheezing. Sad for her tho, though I think it was a Christmas gift or something.

With regards to the gimbal, oh  'sugar', to be honest although you can possibly glue it I think you would do best to send it in for repair. I would always have a worry that a glue job would fail in flight and might bring the drone down with it and possibly hurt someone.

With regards to VPS, what Dirty Bird says about the hard wood surface probably NOT being a suitable surface is, I think, correct.
The surface appears to be quite reflective and the pattern VERY uniform i.e. not distinctive. I would also question whether the drone was ever high enough for the VPS to work, it might need at least 50cm to work.
I fly indoors a lot, between the Mavic Mini  and the Mini 2, several hundred flights, and over a suitable surface with sufficient lighting, VPS position holding is VERY GOOD.

I think there was sufficient light in this flight because, in the absence of GPS AND sufficient light, the drone WILL NOT start it's motors until you press and accept two warning messages in the app.

Since there was no phone connected then UNLESS you had done that earlier and subsequently disconnected the phone there would have been no way for the drone to start its motors if the lighting was poor.

I get those warnings with virtually ever indoor flight because my launch surface is invariably dark but once the drone gets into the air it realises that there is enough light for VPS to work and holds position perfectly, so much so that I have left the room, drone and controller and gone to make a pot of tea and, when I got back, the drone was hovering exactly where I left it.

I really would suggest that you contact DJI with regards to them checking the Drone's DAT.

Who knows, given the way the drone flew an analysis from the actual recorded data might reveal a fault in the drone and if the drone is still under warranty it might be considered a warranty repair. Given the possible blade break that's a slim hope but a hope none the less.

Drones have survived the loss of 1/2 prop i.e. one entire blade and a fair proportion of the prop hub, and been controllable but they did have height to play with and clear space around them at the time of the loss. (Two mavic air type drones in threads in here and or MavicPilots.)

Sean-bumble-bee Posted at 12-27 13:27
With regards to the gimbal, oh  'sugar',  to be honest although you can possibly glue it I think you would do best to send it in for repair. I would always have a worry that a glue job would fail in flight and might bring the drone down with it and possibly hurt someone.

With regards to VPS what Dirty Bird says about the hard wood surface probably NOT being a suitable surface is, I think, correct.

Since there was no phone connected then UNLESS you had done that earlier and subsequently disconnected the phone there would have been no way for the drone to start its motors if the lighting was poor.

That is probably not true on all drones, because I have definitely been able to turn on the motors on my drone (Mavic Air 2) without GPS AND sufficient lighting... On the Mini 2 as far as I remember (from flying my friend's mini 2) that once you accept the warning at least once, it remembers it forever, however I can't say for sure, that was just my experience.

Sean-bumble-bee Posted at 12-27 13:27
With regards to the gimbal, oh  'sugar',  to be honest although you can possibly glue it I think you would do best to send it in for repair. I would always have a worry that a glue job would fail in flight and might bring the drone down with it and possibly hurt someone.

With regards to VPS what Dirty Bird says about the hard wood surface probably NOT being a suitable surface is, I think, correct.

I have updated the pictures

deleted typos

Yaros1 Posted at 12-27 13:48
That is probably not true on all drones, because I have definitely been able to turn on the motors on my drone (Mavic Air 2) without GPS AND sufficient lighting... On the Mini 2 as far as I remember (from flying my friend's mini 2) that once you accept the warning at least once, it remembers it forever, however I can't say for sure, that was just my experience.

With regards to ".....because  I have definitely been able to turn on the motors on my drone (Mavic  Air 2) without GPS AND sufficient lighting.....". Can you clarify that please, do you mean you were able to start the motors with insufficient GPS and with insufficient lighting? If so and just out of curiousity, how do you know the lighting was insufficient?
The above aside, my post is dealing with a Mini 2, not an Air 2.


With regards to "On the Mini 2 as far as I remember (from flying my friend's mini 2) that once you accept the warningS at least once "  I say that with "UNLESS you had done that earlier and subsequently disconnected the phone...... ".


However the drone "remembers" ONLY for the rest of the drone switch on, NOT forever. The next time you switch the drone on you have to go through the two warnings/acceptances again.

I have gone through that procedure so often that I no longer remember the contents of the warnings and dont look at them, I just press whatever I have to press.

IRMMZ 1 Posted at 12-27 14:09
I have updated the pictures

Now we have to wait and see if a Mech Eng etc. can spot anything.

A real mystery.  

IRMMZ 1 Posted at 12-27 12:13
I always do a preflight check, this time I still found no damage. Then the drones propeller broke off on takeoff and flew into the wall.

Perhaps you were a bit lax in your inspection.  Did you just look at it?  Or did you examine it?  Is this a DJI prop, or an aftermarket one?  A real exam would possibly include a little blade flexing while looking closely at the hub of the prop to see if any hidden cracks might show up.  Props don't just fly apart because you woke them up too early or whatever.  It had to be flawed or damaged and it didn't show up to a normal glance at them.

Not trying to pick on you, but they don't just fly apart on their own.

AG0N-Gary Posted at 12-28 04:38
Perhaps you were a bit lax in your inspection.  Did you just look at it?  Or did you examine it?  Is this a DJI prop, or an aftermarket one?  A real exam would possibly include a little blade flexing while looking closely at the hub of the prop to see if any hidden cracks might show up.  Props don't just fly apart because you woke them up too early or whatever.  It had to be flawed or damaged and it didn't show up to a normal glance at them.

Not trying to pick on you, but they don't just fly apart on their own.

I always examine my props closely, for the mini 2 I looked at the hub area and the main prop. I spend about a good minute looking at all the props. And these propellers are the stock ones the drone comes with. I have never replaced them.

IRMMZ 1 Posted at 12-28 10:04
I always examine my props closely, for the mini 2 I looked at the hub area and the main prop. I spend about a good minute looking at all the props. And these propellers are the stock ones the drone comes with. I have never replaced them.

Are you going into this extreme detail with the expectation that DJI needs to take responsibility for your drone?