My Zoom flew away

[Teck]

battery dislodged, propeller broken broken, strong wind are common fly away issue.

Good analytical skill from Sar104 that helps many pilots to avoid such situations. Thank you.

 

[Thomas B]

battery dislodged, propeller broken broken, strong wind are common fly away issue.

Good analytical skill from Sar104 that helps many pilots to avoid such situations. Thank you.

Actually the strong winds cause Blow Away issues

 

[Gilbertlopez1]

That's the file. The evidence is circumstantial but very suggestive. Looking at elevator input, pitch and forwards velocity shows the following at the end of the flight - the aircraft is flying forwards at 19.5 m/s under full forward elevator in sport mode, pitched forwards at 30°. Right at the end, you released the elevator suddenly. The data are not recorded due to telemetry latency, but that will have pitched the aircraft back rapidly to full available backwards pitch (~35°). The maneuver almost certainly dislodged the battery and killed aircraft power, losing motors and telemetry.

View attachment 92392

There is uncertainty on how much braking that maneuver managed before power failure, but likely not much. Based on the last recorded velocity we can estimate the descent trajectory using an aerodynamic drag model for the Mavic 2, giving the following:

View attachment 92393

Plotting the descent track on Google Earth:

View attachment 92394

The far yellow pin represents the descent if the aircraft didn't significantly brake before losing power - i.e. the furthest it should have travelled. I'd start there and look back towards the last recorded point.

Awesome Decoding, Were Lucky To Have People Here Like You To Nearly Pinpoint Our Fly Away/Lost Drones ??

 

[Skyler King III]

That's so impressive!! I have much to learn

Best advice I can give is "avoid sport mode". IMHO. I see no reason to use it. FWIW

 

[Ron Hervey]

This is exactly why I joined this forum. And due to the great info in this thread the OP had a favorable result that otherwise could have been a total loss. Great work guys!

 

[ian4c]

I am just amazed.....what an amazing lot you are here.......

 

[sar104]

holy **** how? I was thinking the battery couldn't have ejected out as it was in fast forward flight.

During the eventual deceleration, yes - but consider what happens when the FC puts on the brakes. The initial response is a rapid rotation from forwards pitch to backwards pitch, which will tend to lift the back of the battery. Somewhat counter-intuitive I know, but there is enough documented history of this exact mechanism that we know it's real.

 

[AntDX316]

Yea, but I often hike for miles to get to a rural AZ location... rather lug the batteries than miss a distant shot.

Do you charge the smart controller while on the hike?

 

[AntDX316]

During the eventual deceleration, yes - but consider what happens when the FC puts on the brakes. The initial response is a rapid rotation from forwards pitch to backwards pitch, which will tend to lift the back of the battery. Somewhat counter-intuitive I know, but there is enough documented history of this exact mechanism that we know it's real.

I saw the telemetry delay after rereading and deleted it but you quoted so it's kept forever. How long did it take to calculate everything?

 

[Thomas B]

Do you charge the smart controller while on the hike?

No... not usually. I’m hiking really rural. Either my SC or my CS will run through at least 6 M2P batteries.... if I use the CS I can carry 2 or 3 batteries for it.... more than enough for my 10 drone batteries. I do have a car charger I use sometimes.

 

[DanMan32]

The M2 battery latches are rather weak. One of the latches on one of my batteries definitely is weaker and doesn't stick out as far as others. It only has a mm or two.

As for alerting if not latched. Circuits are supposed to sense both latches independently (I've tested by pressing only one latch button or the other) but I've gotten a green light with battery cocked where only one side is not latched which originally had me believe both latches had to be pressed in before it would be sensed.

This suggests the latch that's not secure is not pressed in far enough for the micro switch to sense it when battery is slightly unlatched only on one side.

 

[sar104]

I saw the telemetry delay after rereading and deleted it but you quoted so it's kept forever. How long did it take to calculate everything?

I have programmed functions to do all the common analysis, so approximately 100 ms or so total.

I could delete the quote too, but then the conversation would be all messed up.

 

[AntDX316]

I have programmed functions to do all the common analysis, so approximately 100 ms or so total.

I could delete the quote too, but then the conversation would be all messed up.

yeah, best way to do analysis

 

[AntDX316]

No... not usually. I’m hiking really rural. Either my SC or my CS will run through at least 6 M2P batteries.... if I use the CS I can carry 2 or 3 batteries for it.... more than enough for my 10 drone batteries. I do have a car charger I use sometimes.

show some footage

 

[Thomas B]

show some footage

Working on the next one... but here’s one

 

[fr4nszzz]

I CAN'T BELIEVE IT!!!!!!!!!!!!!!!!!!!!!! I FOUND IT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

EXACTLY WHERE SAR104 SAID IT WOULD BE!!!!!!!!!!!!!!!!! Not just close, but RIGHT WHERE HE SAID IT WOULD BE. She's got a couple broken legs but at least I have the carcass I can send back to DJI and hopefully get a replacement/repair under the Refresh program.

THANKS A MILLION SAR104 . . . bona fide genius!!!!!!!!!!!

Great news sar104 did it again a great job.. now i know that the sport mode can cause enough force to eject the battery out..

 

[Safewaves]

I lost my Mavic 2 Enterprise zoom today. I was 10 minutes into my 3rd battery for the day. No wind. Drone was stationary and i broadcast a message on the speaker. Drone was 30 metres away and all of a sudden did a fly away at full speed. I tried to control but no good. Pressed Rth button but no good. Logs show it was doing 20m/s and within seconds it was in the ocean 350mtr out. What do i do next?

 

[sirbadger]

I lost my Mavic 2 Enterprise zoom today. I was 10 minutes into my 3rd battery for the day. No wind. Drone was stationary and i broadcast a message on the speaker. Drone was 30 metres away and all of a sudden did a fly away at full speed. I tried to control but no good. Pressed Rth button but no good. Logs show it was doing 20m/s and within seconds it was in the ocean 350mtr out. What do i do next?

I'd start by making your own thread and post your logs.

 

[AntDX316]

Working on the next one... but here’s one

Interesting but it all looks the same.

 

[tcmjhb]

Search and Rescue has never been so interesting. The horror and despair of drone loss so recognizable from these posts, followed by the cool inputs of the King. And so despair turns to unbelievable joy as the craft is reunited with pilot
Only - sar104 - has been seen to bring such amazing results. Well done yet again