Lost?

[Loft_in_spain]

Hi.
My first post, be gentle.

Flying last weekend I stupidly put my mavic downwind, and although I started the RTH mode in what I thought was good time. It wasn't.
The mavic couldn't fight against the headwind.

Anyway, long story short, part way into the RTH, my phone lost connection with the controller.

However, the controller maintained contact with the mavic, and I watched on the screen as it flew on a further 2,000 feet (closer to home) before going into emergency landing mode.

The flight data on the phone stops at the point where the phone lost connection with the controller.

It shows the mavic 6,000ft from home, 700ft AGL (I was on a hill 600ft high and my RTH mode is set to 110ft - 30m), and travelling at 8mph towards the home point. No vertical speed at that point.

I uploaded the flight data to DJI, who merely confirmed the last location as shown on my phone, and confirmed I was an idiot for sending it up in high wind. All of that I knew.

I took the dat files from the controller, in the hope they might contain position details for when the mavic went into emergency landing mode.
But DJI tell me those files only contain data about pilot input.

Does anyone have any suggestion as to anything else I can try to give me a reasonable search area, or is my mavic lost for good?

Cheers
Loft_in_Spain

 

[msinger]

Does anyone have any suggestion as to anything else I can try to give me a reasonable search area, or is my mavic lost for good?

Check out your TXT flight log to see if it explains what happened. You can upload and view it online here. If you'd like other people to review and comment on your flight log, then please post a link back here after you upload it.

 

[sar104]

Hi.
My first post, be gentle.

Flying last weekend I stupidly put my mavic downwind, and although I started the RTH mode in what I thought was good time. It wasn't.
The mavic couldn't fight against the headwind.

Anyway, long story short, part way into the RTH, my phone lost connection with the controller.

However, the controller maintained contact with the mavic, and I watched on the screen as it flew on a further 2,000 feet (closer to home) before going into emergency landing mode.

The flight data on the phone stops at the point where the phone lost connection with the controller.

It shows the mavic 6,000ft from home, 700ft AGL (I was on a hill 600ft high and my RTH mode is set to 110ft - 30m), and travelling at 8mph towards the home point. No vertical speed at that point.

I uploaded the flight data to DJI, who merely confirmed the last location as shown on my phone, and confirmed I was an idiot for sending it up in high wind. All of that I knew.

I took the dat files from the controller, in the hope they might contain position details for when the mavic went into emergency landing mode.
But DJI tell me those files only contain data about pilot input.

Does anyone have any suggestion as to anything else I can try to give me a reasonable search area, or is my mavic lost for good?

Cheers
Loft_in_Spain

If you post the txt flight log then we can make an estimate of the autoland location based on RTH speed and battery depletion rate prior to the phone disconnect.

 

[Loft_in_spain]

Thanks guys.

This is the flight record:

DJI Flight Log Viewer - PhantomHelp.com

Not sure what the last minute change of direction was, caught by the wind perhaps?

Remember, the altitude was 112 feet above the take off level. Take off level was 600 feet above ground level. So aircraft was at about 700 ft above ground level.

Any suggestions gratefully received.

 

[sar104]

Thanks guys.

This is the flight record:

DJI Flight Log Viewer - PhantomHelp.com

Not sure what the last minute change of direction was, caught by the wind perhaps?

Remember, the altitude was 112 feet above the take off level. Take off level was 600 feet above ground level. So aircraft was at about 700 ft above ground level.

Any suggestions gratefully received.

The critical low battery level (forced landing) was set to 10%. Looking at the battery % depletion rate and speed during the RTH period, it appears that the aircraft would have continued for another 160 s or so before autolanding, and extrapolating speed and distance, travelled around 560 m:



Looking at the recorded variation in speed and heading for the same period indicates that its speed varied between 2.3 m/s and 4.2 m/s and its heading varied between 296° and 330°:



Using those values to bound the travel after the last recorded point gives an area as shown below:

 

[kakao]

Hi.
My first post, be gentle.

Flying last weekend I stupidly put my mavic downwind, and although I started the RTH mode in what I thought was good time. It wasn't.
The mavic couldn't fight against the headwind.

Anyway, long story short, part way into the RTH, my phone lost connection with the controller.

However, the controller maintained contact with the mavic, and I watched on the screen as it flew on a further 2,000 feet (closer to home) before going into emergency landing mode.

The flight data on the phone stops at the point where the phone lost connection with the controller.

It shows the mavic 6,000ft from home, 700ft AGL (I was on a hill 600ft high and my RTH mode is set to 110ft - 30m), and travelling at 8mph towards the home point. No vertical speed at that point.

I uploaded the flight data to DJI, who merely confirmed the last location as shown on my phone, and confirmed I was an idiot for sending it up in high wind. All of that I knew.

I took the dat files from the controller, in the hope they might contain position details for when the mavic went into emergency landing mode.
But DJI tell me those files only contain data about pilot input.

Does anyone have any suggestion as to anything else I can try to give me a reasonable search area, or is my mavic lost for good?

Cheers
Loft_in_Spain

Sorry for your loss, did you try the Sport mode at any given time ..?

 

[PCBrowne]

Hi.
My first post, be gentle.

Flying last weekend I stupidly put my mavic downwind, and although I started the RTH mode in what I thought was good time. It wasn't.
The mavic couldn't fight against the headwind.

Anyway, long story short, part way into the RTH, my phone lost connection with the controller.

However, the controller maintained contact with the mavic, and I watched on the screen as it flew on a further 2,000 feet (closer to home) before going into emergency landing mode.

The flight data on the phone stops at the point where the phone lost connection with the controller.

It shows the mavic 6,000ft from home, 700ft AGL (I was on a hill 600ft high and my RTH mode is set to 110ft - 30m), and travelling at 8mph towards the home point. No vertical speed at that point.

I uploaded the flight data to DJI, who merely confirmed the last location as shown on my phone, and confirmed I was an idiot for sending it up in high wind. All of that I knew.

I took the dat files from the controller, in the hope they might contain position details for when the mavic went into emergency landing mode.
But DJI tell me those files only contain data about pilot input.

Does anyone have any suggestion as to anything else I can try to give me a reasonable search area, or is my mavic lost for good?

Cheers
Loft_in_Spain

Hey its my first post to, but I think very good idea is to put sticker (Dyno label etc) on mavic arms with name and phone number and reward offered for return so if some honest person finds it they will call and brighten up your day. Cheers
Peter Australia

 

[mel.m]

You don't have to be in trouble to learn things hear just read and learn good idea Peter. Hope u find her PC Browne

 

[Wayno1]

Hey its my first post to, but I think very good idea is to put sticker (Dyno label etc) on mavic arms with name and phone number and reward offered for return so if some honest person finds it they will call and brighten up your day. Cheers
Peter Australia

Welcome fellow Aussie!!

 

[Goaltender]

Hi.
My first post, be gentle.

Flying last weekend I stupidly put my mavic downwind, and although I started the RTH mode in what I thought was good time. It wasn't.
The mavic couldn't fight against the headwind.

Anyway, long story short, part way into the RTH, my phone lost connection with the controller.

However, the controller maintained contact with the mavic, and I watched on the screen as it flew on a further 2,000 feet (closer to home) before going into emergency landing mode.

The flight data on the phone stops at the point where the phone lost connection with the controller.

It shows the mavic 6,000ft from home, 700ft AGL (I was on a hill 600ft high and my RTH mode is set to 110ft - 30m), and travelling at 8mph towards the home point. No vertical speed at that point.

I uploaded the flight data to DJI, who merely confirmed the last location as shown on my phone, and confirmed I was an idiot for sending it up in high wind. All of that I knew.

I took the dat files from the controller, in the hope they might contain position details for when the mavic went into emergency landing mode.
But DJI tell me those files only contain data about pilot input.

Does anyone have any suggestion as to anything else I can try to give me a reasonable search area, or is my mavic lost for good?

Cheers
Loft_in_Spain

Have you hit the three bars in the top right corner of your phone on the opening page of dji mavic pro screen
then push find my drone
it shows where it is even when the battery is turned off

 

[Wayno1]

Have you hit the three bars in the top right corner of your phone on the opening page of dji mavic pro screen
then push find my drone
it shows where it is even when the battery is turned off

That's cool! Didn't know that, thanks for sharing

 

[Loft_in_spain]

Sorry for your loss, did you try the Sport mode at any given time ..?

Thanks. No, I was in a bit of a panic once I lost phone contact. In hindsight I should also have dropped its altitude to try and get it into the lea of the mountain. Next time...

 

[Loft_in_spain]

The critical low battery level (forced landing) was set to 10%. Looking at the battery % depletion rate and speed during the RTH period, it appears that the aircraft would have continued for another 160 s or so before autolanding, and extrapolating speed and distance, travelled around 560 m:

View attachment 30588

Looking at the recorded variation in speed and heading for the same period indicates that its speed varied between 2.3 m/s and 4.2 m/s and its heading varied between 296° and 330°:

View attachment 30589

Using those values to bound the travel after the last recorded point gives an area as shown below:

View attachment 30590

Wow!
That is brilliant, thank you so much for doing that. It's easy more useful than the info DJI gave me.
I don't know how you did it but thank you for doing it.
I shall go out today and have a look around that new search area.
Cheers [emoji16]

 

[Loft_in_spain]

Hey its my first post to, but I think very good idea is to put sticker (Dyno label etc) on mavic arms with name and phone number and reward offered for return so if some honest person finds it they will call and brighten up your day. Cheers
Peter Australia

Thank you. Yes, that is a very good idea and something I will do in future.

 

[Loft_in_spain]

Have you hit the three bars in the top right corner of your phone on the opening page of dji mavic pro screen
then push find my drone
it shows where it is even when the battery is turned off

I did try that. It only took me to the last recorded location (before the phone disconnected), but I know it was still 700 ft in the air at that point

 

[eek]

Dji should just increase the drone speed when in RTH if speed is below certain value. So many drones lost because people forget about sport mode..

 

[Loft_in_spain]

Dji should just increase the drone speed when in RTH if speed is below certain value. So many drones lost because people forget about sport mode..

The other thing that would have been useful is if the battery maintained a tiny bit of charge once landed, and gave off some kind of signal every minute.
Even disconnected, the controller could be programmed to "listen" for the signal.

That way, if you were searching close to where it landed, and it's perhaps in a tree, you'd stand a better chance of getting its location.

I noticed there is a "make a beep" and a "flash lights" command on the app. But if the drone is down with a completely dead battery and no life in its circuits, it won't respond.

I'm also going to look at getting a tracker to attach to it.

Thanks everyone for your help and suggestions, the hunt continues....

 

[colinfowler]

The other thing that would have been useful is if the battery maintained a tiny bit of charge once landed, and gave off some kind of signal every minute.

this would only reduce flight time more, the 10% critical would be reached sooner and still land.

Thanks everyone for your help and suggestions, the hunt continues....

good luck and I hope you find it

 

[Loft_in_spain]

this would only reduce flight time more, the 10% critical would be reached sooner and still land.

good luck and I hope you find it

I used to do geocaching years ago. They introduced a cache which was basically a little beacon. The idea was you got yourself within so many feet of the coordinates, then the phone app would "listen" for the beacon.
I can't remember what they were called (cheap, or chirp), but they ran off a tiny battery and lasted months.

Could even be done with a tiny rechargeable battery inside the drone similar to the backup battery in a computer that keeps the date and time going. Do they still have those in them? [emoji23]

Anyway, that's all adding to the weight and circuits, and I'm not helping myself find my drone.

I suppose the best solution is not to have an idiot at the controls

 

[colinfowler]

I suppose the best solution is not to have an idiot at the controls

don't beat yourself up we are all idiots at some time, we just have to learn from our mistakes and that makes us all smart