Mavic Pro disappeared

[judoka]

Any ideas what might have happened here?
I hit RTH and saw that it was heading home then it just vanished. I lost signal and the signal never came back along with MP never returning home. Everything looks pretty good to my untrained eye. A couple warnings about wind gusts but nothing else jumps out at me. I'm also not sure if I am going to be able to find this guy. I looked around the last known location and tried to look along the path back home as best I could but didn't see anything.

DJI Flight Log Viewer | Phantom Help

Upload and view flight logs from your DJI drones

www.phantomhelp.com

Thanks in advance for any assistance.

 

[MAvic_South_Oz]

Abrupt ending.
Nothing weird about the flight in that Phantom Help review I feel, gut feel is battery fell out.

Although you got a few wind warnings at 215', then went up to the final altitude about 300', I don't think this was an issue overall, the M1P seemed to handle the flight both ways with ease.

Maybe one of the numerous flight analysis gurus can give you an idea of where to look, perhaps at this stage @sar104 is the man here to tag.

 

[MadMaqx]

I bet depending on your wind warning it force landed was it a red warning?

 

[judoka]

I think there were 2 wind warnings but it flew for quite a bit after any wind warnings and then switched over to Go Home. Looking at the speed and altitude it doesn't appear that wind was a factor. It just vanished into thin air.

 

[RodPad]

Are you friends with the property owners where it last was?
Lost battery or battle with a gun?

Bird strike, you still would receive some data for a few seconds?

Rod

 

[Mavic Mac]

@judoka

I think you may have missed seeing some of your warnings and messages - these were taken off your flight log

Strong interference. Fly with caution.
High wind velocity. Fly with caution and land in a safe place ASAP
High wind velocity. Fly with caution and land in a safe place ASAP
High wind velocity. Fly with caution and land in a safe place ASAP
Flight distance may exceed line-of-sight. Fly with caution
High wind velocity. Fly with caution and land in a safe place ASAP
High wind velocity. Fly with caution and land in a safe place ASAP
Weak signal. Avoid blocking the antennas and keep the antennas parallel to and facing toward the aircraft during flight
Downlink Restored (after 0m 1.1s)
RTH: Preascending
RTH: Heading alignment; Aircraft is returning to the Home Point. Minimum RTH Altitude is 40m. You can reset the RTH Altitude in Remote Controller Settings after cancelling RTH if necessary
RTH: Cruise
Downlink Restored (after 0m 1.9s)
Downlink Restored (after 0m 1.1s)
Downlink Restored (after 0m 4.3s)
Downlink Restored (after 0m 1.6s)
Weak signal. Avoid blocking the antennas and keep the antennas parallel to and facing toward the aircraft during flight.
Downlink Restored (after 0m 1.1s)

 

[Meta4]

I think you may have missed seeing some of your warnings and messages - these were taken off your flight log

Wind was not a problem for this flight which was into a headwind that reduced the speed in Sport Mode to <30mph on the way out and coming back with the wind.
DJI's warning to land ASAP is misleading and the wind was completely manageable if handled properly as the OP did.
The Mavic had no trouble maintaining full RTH speed coming home.

 

[Mavic Mac]

Wind was not a problem for this flight which was into a headwind that reduced the speed in Sport Mode to <30mph on the way out and coming back with the wind.
DJI's warning to land ASAP is misleading and the wind was completely manageable if handled properly as the OP did.
The Mavic had no trouble maintaining full RTH speed coming home.

I posted those in response to his statement I think there were 2 wind warnings

 

[sar104]

That's an unusual one. The aircraft was in stable RTH when the downlink abruptly dropped. There did not appear to be any of the usual precursor sudden maneuvers that typically precede a battery becoming dislodged. However, in the absence of a sudden failure, the aircraft had enough battery reserve to get home, and it was aided by a tailwind.



That suggests some kind of sudden failure. The mobile device DAT file ending FLY116.DAT might contain clues. However, if that is what happened and the aircraft shut down, the usual finite difference solution for the descent track should be fairly accurate. With the Mavic Pro drag model, that yields the following:



Plotting that on Google Earth shows the following predicted crash point:

 

[MAvic_South_Oz]

If you have a chance to go look for the body @judoka then best of luck in finding it.

 

[judoka]

I have already went over the last known position pretty well twice now on foot and covered enough of the surrounding area that I should have been over the predicted crash site.

I don't have a .dat file synched on my primary phone like the .txt file is for that flight. I'll check the old phone I was actually using with the controller at the time.

I will likely go back over the last known location another time or several before I give up. I'll make sure to drop a pin for the projected crash site to see that I definitely hit that point. Thanks for the help with that.

 

[sar104]

I have already went over the last known position pretty well twice now on foot and covered enough of the surrounding area that I should have been over the predicted crash site.

I don't have a .dat file synched on my primary phone like the .txt file is for that flight. I'll check the old phone I was actually using with the controller at the time.

I will likely go back over the last known location another time or several before I give up. I'll make sure to drop a pin for the projected crash site to see that I definitely hit that point. Thanks for the help with that.

That sounds like a good plan. Note that the predicted site is around 60 meters from the last recorded position, so not that close. It's very likely that it is there.

 

[Martysticks]

question: How can a battery fall out of a Mavic Pro? Isn't the battery on top? I can see it as a possibility with the Mavic Air, but a Pro?

 

[sar104]

question: How can a battery fall out of a Mavic Pro? Isn't the battery on top? I can see it as a possibility with the Mavic Air, but a Pro?

It doesn't generally fall out, but sudden changes in pitch can dislodge it enough to disconnect it momentarily if it is not properly latched. That's unlikely to be what happened in this case however.

 

[JPC]

Reading this history with a great deal of interest, albeit not directly involved, so forgive me. But for my own understanding where/how did you download the flight data from? and then mapping it to google maps? I'd certainly like to be able to do that with my own records as I am monitoring a highway build programme and being able to stitch photos/data to the ground map would be very useful indeed.

 

[sar104]

Reading this history with a great deal of interest, albeit not directly involved, so forgive me. But for my own understanding where/how did you download the flight data from? and then mapping it to google maps? I'd certainly like to be able to do that with my own records as I am monitoring a highway build programme and being able to stitch photos/data to the ground map would be very useful indeed.

The methods are described here - which is also the link under all my posts:

Mavic Flight Log Retrieval and Analysis Guide

With the introduction of the Mavic Mini there has been a noticeable uptick in the number of posts requesting help with lost or crashed aircraft. While there is plenty of help and advice available on this forum, and detailed guidance and options on several other websites, I thought that perhaps a...

mavicpilots.com

 

[judoka]

That's how I did it, read the pinned post that sar104 references. I am in IT so I generally find things like this to be pretty easy but I think just about anybody should be able to follow these procedures.

 

[BigAl07]

question: How can a battery fall out of a Mavic Pro? Isn't the battery on top? I can see it as a possibility with the Mavic Air, but a Pro?

It's important to also note that any "Puffing/Swelling" of the MP battery can exasperate this problem. As the battery swells the only point of relief is on the under side of the battery. Many people will use extra pressure to "Force" the swollen battery to engage the locking mechanisms. In essence you now have a "Spring Loaded Battery Launch System".

This may or may not have anything to do with the problem in the OP's case but it is worth noting especially since many of the MP batteries are starting to get some age and wear on them.

 

[sar104]

It's important to also note that any "Puffing/Swelling" of the MP battery can exasperate this problem. As the battery swells the only point of relief is on the under side of the battery. Many people will use extra pressure to "Force" the swollen battery to engage the locking mechanisms. In essence you now have a "Spring Loaded Battery Launch System".

This may or may not have anything to do with the problem in the OP's case but it is worth noting especially since many of the MP batteries are starting to get some age and wear on them.

That's a good point - an expanding battery is one mechanism that could cause a disconnect in stable flight.

 

[BigAl07]

That's a good point - an expanding battery is one mechanism that could cause a disconnect in stable flight.

I disposed of (3) swollen MPP batteries just a few weeks ago. In my testing I found that the one with the most swelling would "Leap" out of the cradle when the releases were pressed. Next time I have one that's swollen to that degree I'll try and make a snippet of it to share.