Mavic Pro Spiraled out of the sky!

[MN_Jack76]

After flying smaller drones for many years and this Mavic Pro for about a year I got cocky. I started to wonder how these things even do crash?

 

[MN_Jack76]

Or this file?

If you look at the detailed pitch/roll/yaw response you see the following:

View attachment 78991

It certainly has the attitude signature of a lost prop or failed motor. The initial yaw is CCW, but the subsequent spin is CW, which implies that it lost a CW motor/prop. The definitive information should be in the DAT file (FLY112.DAT).

@MN_Jack76 - if you can retrieve that DAT file from your mobile device that would help.

Mobile device DAT file: How to retrieve a V3.DAT from the tablet

@sar104 Is this the dat file you can read?

 

[Filipok]

Yep.. Same thing happened to me. I was using counterfeit blades that I didn't know were fake. $420 (new camera and two new legs later). The prop broke at the hub, losing half of the propeller. Now I fly Master Airscrew props 100%. I feel they're MUCH sturdier than OEM, more efficient, and quieter. My RPMs fell by 75 to 100 with them. Less stress on the engines, less vortex drag, etc. They are the same price as OEM.

 

[sar104]

Or this file?

@sar104 Is this the dat file you can read?

The first one that you posted was correct. The motor data are quite unusual.



None of that looks like a lost prop, which is characterized by a sudden motor speed increase to near maximum. It doesn't really look like anything I've seen before - both the motor command and motor speed data are strange.

Looking at the accelerometer and rate gyro:



The nearly 2 g acceleration to the left leaves me wondering if there was a collision in the air, although how that would account for the motor data is still a mystery to me.

@BudWalker?

 

[DDS]

Wow... I'm happy that I didn't crash it, yet it depresses me to look at. This is a very expensive malfunction. I'm glad it didn't damage any property and that I got to meet some nice neighbors who called it in. Does this failure happen often? I may just try to fix it and sell it. Too risky. Again I sure do appreciate your knowledge!

Feel FREE to send it in for a free inspection, free shipping both ways. You only pay if we fix.
Also use "mavicpilots" for $35 off the repair should you decide to fix it

sidenote
would love to bring this baby back to life after falling out of the sky @ 400ft

glad no one was hurt

click here to submit your free quote and inspection

 

[Paul2660]

Bird Strike, they fly at night folks.

Paul C

 

[BudWalker]

The first one that you posted was correct. The motor data are quite unusual.

View attachment 79050

None of that looks like a lost prop, which is characterized by a sudden motor speed increase to near maximum. It doesn't really look like anything I've seen before - both the motor command and motor speed data are strange.

Looking at the accelerometer and rate gyro:

View attachment 79051

The nearly 2 g acceleration to the left leaves me wondering if there was a collision in the air, although how that would account for the motor data is still a mystery to me.

@BudWalker?

It does seem like some impact from the right could have started this. The 2 g acceleration occurred 100 ms before the motor data started changing.

As for the unusual motor data one possibility is that both of the front props were affected. The image in #21 shows a CCW and CW prop being damaged. Each side of the MP (front, right, back, left) has a CCW/CCW pair. The motorCommanded data shows both front motors (black and blue plots) being commanded higher. That's consistent with both front props being damaged.


Assuming that it was the front two props the leftFront appears to have been the most damaged. This is consistent with the CW rotations.

Normally we see faster rotations and more tumbling. It's a little hard to tell but it seems that after the initial end over end tumble the MP stayed upright (barely) and managed to descend rotating relatively slowly without tumbling. Although two props were affected the resulting flight characteristics could have been easier to manage. The net angular momentum was smaller than just on prop being lost, and the propulsion loss wasn't confined to just one corner.

 

[sar104]

It does seem like some impact from the right could have started this. The 2 g acceleration occurred 100 ms before the motor data started changing.

As for the unusual motor data one possibility is that both of the front props were affected. The image in #21 shows a CCW and CW prop being damaged. Each side of the MP (front, right, back, left) has a CCW/CCW pair. The motorCommanded data shows both front motors (black and blue plots) being commanded higher. That's consistent with both front props being damaged.
View attachment 79090

Assuming that it was the front two props the leftFront appears to have been the most damaged. This is consistent with the CW rotations.

Normally we see faster rotations and more tumbling. It's a little hard to tell but it seems that after the initial end over end tumble the MP stayed upright (barely) and managed to descend rotating relatively slowly without tumbling. Although two props were affected the resulting flight characteristics could have been easier to manage. The net angular momentum was smaller than just on prop being lost, and the propulsion loss wasn't confined to just one corner.

Agreed on the rotation/oscillation frequency and the motor data. On the 2 g acceleration, I wonder now if that's not an impact signature, since there are several equally large x and y accelerations later in the record. Maybe just the thrust imbalance is enough to create those excursions.

 

[BudWalker]

Agreed on the rotation/oscillation frequency and the motor data. On the 2 g acceleration, I wonder now if that's not an impact signature, since there are several equally large x and y accelerations later in the record. Maybe just the thrust imbalance is enough to create those excursions.

That is a little troublesome. For an AC moving at 17 m/sec it's more likely that it ran into something than something ran into it from the side. But, the 2 g acceleration came before the motor data changes. Would be nicer if the acceleration were on the X axis.

 

[kidroc]

Yep.. Same thing happened to me. I was using counterfeit blades that I didn't know were fake. $420 (new camera and two new legs later). The prop broke at the hub, losing half of the propeller. Now I fly Master Airscrew props 100%. I feel they're MUCH sturdier than OEM, more efficient, and quieter. My RPMs fell by 75 to 100 with them. Less stress on the engines, less vortex drag, etc. They are the same price as OEM.

I’ve been flying with Masters for a year now I love those props!!

 

[BerndM]

Are the props you show in the picture in post #21 from the actual crashed Mavic?
If so, it seems like the CW prop came apart in the air and the CCW (bent) one got damaged on impact.

 

[jpbluzharp]

Just had that happen to me in Maine... watch at 127 feet. I believe a gull took me out. They were very aggressive up there. My Mavic was in line with the sun so I couldn’t see it at the strike but I sure saw the video image spinning on my IPad mini. Heard the crash too about 160 feet away from me. Seagull Attack in York, Maine

 

[Prismatic]

... <*snip*> ...

@BudWalker and @sar104 are the best drone incident analysts you'll find. Yet it appears there's no definitive answer to what happened. It seems most likely—to me—that your drone collided with a bat or bird, but neither is common at that altitude at that time of day.
¯\_(☯෴☯)_/¯
Anyway, it was just dumb luck (the bad kind), with an infinitesimal chance of repeating. Don't let a bizarre random event steal the joy of flying. Don't forget why you had your bird was barrelling home. ?

 

[Cobra28409]

Last Saturday while I was flying my Mavic Pro and it was few blocks away, I switched to sport mode, which I have used many times as it is fun to watch it streak across the night sky overhead. It was only about two blocks away and coming back to home at around 35mph when it suddenly started spinning and dropping in a crash. After a lot of thinking what went wrong I wondered if I was lowering it's altitude and it hit a tree. I was able to pull up a replay of the flight and it was at 399ft when it all went wrong. It was cruising along fine and suddenly and violently spun to a crash. I wondered things like "did I hit a bat or something in the air"? It still had power as it spun down because I did see live camera footage spinning as it crashed. A nice neighbor called me the next day saying he had found it. The camera is ripped off, the body is broke and at least one arm is broken. Now I am roughly $400 in repair parts if I do the repairs myself. It went from a perfectly running machine to a sudden spinning crash with no warning. I also know it was at 400 ft because looking back on the log it said it was at 400 and even at a descent of 35mph it took awhile to hit the ground. The battery showed 53% when it crashed and it was transmitting a strong signal of a spinning camera view to my ipad. In the warning logs there was nothing helpful, just the usual max altitude reached and so on. Did I hit something? Did a motor fail and if so, does it happen often? Did I suffer a propeller failure? I did have quiet propellers installed that may have been aftermarket. All the propeller hubs were still attached to the motors and all the hinge pins were intact. Many of the propeller blades were bent, impacted or snapped off. Any insight into what could have caused this would be greatly appreciated as I am afraid to fly the thing again if I do manage to get it fixed.

Check you props before each flight for small cracks at ends. When a prop fails it will go into a death sprial.

 

[MN_Jack76]

Feel FREE to send it in for a free inspection, free shipping both ways. You only pay if we fix.
Also use "mavicpilots" for $35 off the repair should you decide to fix it

sidenote
would love to bring this baby back to life after falling out of the sky @ 400ft

glad no one was hurt

click here to submit your free quote and inspection

After a week and Amazon Prime I soldered it back to life and it looks like new! Thank you for your inputs and sorry for the delay in responding. I received a message from this site saying it was in the wrong forum. I stopped getting alerts at that point.

 

[MN_Jack76]

@BudWalker and @sar104 are the best drone incident analysts you'll find. Yet it appears there's no definitive answer to what happened. It seems most likely—to me—that your drone collided with a bat or bird, but neither is common at that altitude at that time of day.
¯\_(☯෴☯)_/¯
Anyway, it was just dumb luck (the bad kind), with an infinitesimal chance of repeating. Don't let a bizarre random event steal the joy of flying. Don't forget why you had your bird was barrelling home. ?

It was almost $400 worth of bad luck, but after Amazon Prime and soldering she is good as new. I appreciate the members here!

 

[MN_Jack76]

Are the props you show in the picture in post #21 from the actual crashed Mavic?
If so, it seems like the CW prop came apart in the air and the CCW (bent) one got damaged on impact.

Yes, these were the actual props. And sorry for the late response. This site said I was posting in the wrong area and I stopped getting alerts.

 

[MN_Jack76]

@BudWalker and @sar104 are the best drone incident analysts you'll find. Yet it appears there's no definitive answer to what happened. It seems most likely—to me—that your drone collided with a bat or bird, but neither is common at that altitude at that time of day.
¯\_(☯෴☯)_/¯
Anyway, it was just dumb luck (the bad kind), with an infinitesimal chance of repeating. Don't let a bizarre random event steal the joy of flying. Don't forget why you had your bird was barrelling home. ?

Thank you all for your help! I guess it wasn't my night - lol. You fellow members are awesome!

 

[MN_Jack76]

The first one that you posted was correct. The motor data are quite unusual.

View attachment 79050

None of that looks like a lost prop, which is characterized by a sudden motor speed increase to near maximum. It doesn't really look like anything I've seen before - both the motor command and motor speed data are strange.

Looking at the accelerometer and rate gyro:

View attachment 79051

The nearly 2 g acceleration to the left leaves me wondering if there was a collision in the air, although how that would account for the motor data is still a mystery to me.

@BudWalker?

Thank you very much for looking at the data. I have no idea what happened but after Amazon Prime, $400 (which is a lot for me) and a soldering iron, I test flew i last night and it looks and performs like new. I'm a little afraid to fly this thing much in the future.

 

[MN_Jack76]

It does seem like some impact from the right could have started this. The 2 g acceleration occurred 100 ms before the motor data started changing.

As for the unusual motor data one possibility is that both of the front props were affected. The image in #21 shows a CCW and CW prop being damaged. Each side of the MP (front, right, back, left) has a CCW/CCW pair. The motorCommanded data shows both front motors (black and blue plots) being commanded higher. That's consistent with both front props being damaged.
View attachment 79090

Assuming that it was the front two props the leftFront appears to have been the most damaged. This is consistent with the CW rotations.

Normally we see faster rotations and more tumbling. It's a little hard to tell but it seems that after the initial end over end tumble the MP stayed upright (barely) and managed to descend rotating relatively slowly without tumbling. Although two props were affected the resulting flight characteristics could have been easier to manage. The net angular momentum was smaller than just on prop being lost, and the propulsion loss wasn't confined to just one corner.

I appreciate your help and I have fixed the thing but now I am worried there is something wrong with it. Would you fly it again?