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my mavic pro lost signal to RC

jonnymavic

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At 7000 feet away. Flying at my buddies, Its all pretty much farmers fields. Lost connection with APP and RC RTH was set. but never came back. Looked it up on the find my drone APP. Gave coordinates. Ive tried looking 6xs now. the area it is in is very hard to get in and around. lots of over growth. Ended up getting 4 Ticks and poison ivy. Tomorrow im going to give it one last shot. The bugs are so bad , it is going on day 6. We have had some rain.
here is a flight log if anyone can give me some pointers, would be great
 

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The wind was not in your favor during this flight (see the Airdata wind map here). Since the Mavic was set to return home on signal loss and the calculated wind speed was beyond what the Mavic can handle, it likely drifted further away from the last recorded location after the remote controller disconnected. It would be tough to guesstimate where it could have landed since there is no telling how much (or little) progress it made toward the home point.
 
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Ive looked in that area and can not find it at all. on an android it gives me different coordinates then if i use and apple device it gives me different coordinates . Its not off bt much. My buddy was the only one with a car, and he already had one to many PoPs so it took me about an hour to get to that location. Why wouldn't RTH after signal loss
 
Ive looked in that area and can not find it at all
In the last recorded location? Yes, that makes perfect sense. It's likely nowhere near there.

Why wouldn't RTH after signal loss
Since it had plenty of battery power remaining and it didn't make it back to the home point, the wind was likely too strong.
 
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At 7000 feet away. Flying at my buddies, Its all pretty much farmers fields. Lost connection with APP and RC RTH was set. but never came back. Looked it up on the find my drone APP. Gave coordinates. Ive tried looking 6xs now. the area it is in is very hard to get in and around. lots of over growth. Ended up getting 4 Ticks and poison ivy. Tomorrow im going to give it one last shot. The bugs are so bad , it is going on day 6. We have had some rain.
here is a flight log if anyone can give me some pointers, would be great
This is a case of not paying enough attention unfortunately. I know that’s not what you would like to hear but I am just hear to give you the facts. You took off from a location extremely close to an international airport. I don’t know anything about Canadian laws but I have a feeling you’d need some kind of authorization to fly here. You drone gave you a message that the RTH location was in a restricted zone and to be aware that the drone could not return to the home location through this restricted zone. 75685
 
i was only about 150 feet up. But i really with 90% battery left you would of thought it would of made it back or at least close enough to hear by then
 
Yes you are very correct. it was stupid but are other buddy lives about 1500 feet from where i lost signal and i thought with these open fields it would be no problem. I wasn't going to go any higher. because i knew of the danger.
Last question. Say i some how recover it. Would it still be Done from the rain ?
 
It couldn’t pass through the red area during RTH so If look around the red line.
That's a possibility too if it drifted that far.
 
Thanks for everyone giving me answers. It is a big mistake, but i just want to fly. It was the first real drone i bought. i've had drones but this was my best friend.... Well iv'e got a RC that is pointless to have
 
Sorry for your loss. I understand. I am not meaning to rub salt in a wound.

See post #3 above for why it could not follow your RTH instruction (headwind velocity).

If you are able to replace/recover your drone, and I hope you do, keep this rule I made for myself in mind; always fly out against the wind and back home with it.
 
You think i should give it one last look or just take it for what it is?
I’ve done my best to overlay the drones path with the flysafe map. 75687
Your take off location was just barely in the red zone so I think it must have not even tried to come home or you would have regained connection with it before it hit a red zone. I believe it must have reverted to hovering and autolanded before it totally lost battery life. Did you try find my drone? I bet it is just past the last place you had contact with it. Just my guess. The AirMap data shows winds of 20-25mph but that’s not outside the ability of the aircraft especially in RTH and you had plenty of battery for it to make it back into radio range at least and it also wouldn’t have been flying directly into that wind. I’m sure it was working hard but I just don’t think it would have pushed it significantly off course. That’s just my humble opinion.
 
Last edited:
I’ve done my best to overlay the drones path with the flysafe map. View attachment 75687
Your take off location was just barely in the red zone so I think it must have not even tried to come home or you would have regained connection with it before it hit a red zone. I believe it must have reverted to hovering and autolanded before it totally lost battery life. Did you try find my drone? I bet it is just past the last place you had contact with it. Just my guess. The AirMap data shows winds of 20-25mph but that’s not outside the ability of the aircraft especially in RTH and you had plenty of battery for it to make it back into radio range at least and it also wouldn’t have been flying directly into that wind. I’m sure it was working hard but I just don’t think it would have pushed it significantly off course. That’s just my humble opinion.
Yes that is what i was totally thinking also. Because 2 hrs before that flight. i was flying it from the same home point maybe did a 6000 foot flight and i had no problems. I would hit RTH and i actually always do that, just until i can see it or hear it and then i cancel and play with some of the features until the battery is just about done.
The last coordinates it gave me were 43.187878, -79.930683 it is not the easiest place to walk around. it is an abandon Golf course, for over 10yrs is my guess. because This over growth was a good 6 to 7 feet high in some spots .

i will give it one last shot tomorrow. I just dont want to get anymore Ticks.

Is there a big difference between the MP and the MA because i think i'll be purchasing the Mavic air i dont have enough money to buy the pro right now.
I need to be back up in the air by the weekend.
any other suggestion on which drone to buy for around 6-700 bucks
 
Yes that is what i was totally thinking also. Because 2 hrs before that flight. i was flying it from the same home point maybe did a 6000 foot flight and i had no problems. I would hit RTH and i actually always do that, just until i can see it or hear it and then i cancel and play with some of the features until the battery is just about done.
The last coordinates it gave me were 43.187878, -79.930683 it is not the easiest place to walk around. it is an abandon Golf course, for over 10yrs is my guess. because This over growth was a good 6 to 7 feet high in some spots .

i will give it one last shot tomorrow. I just dont want to get anymore Ticks.

Is there a big difference between the MP and the MA because i think i'll be purchasing the Mavic air i dont have enough money to buy the pro right now.
I need to be back up in the air by the weekend.
any other suggestion on which drone to buy for around 6-700 bucks
You should be able to get a Mavic Pro for that these days. I’d much rather have the Pro than the air to be honest.
 
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Sorry for your loss. Thank you for sharing though as it helps everyone learn from these kind of mistakes.
 
This is one of those events that has a number of abnormal elements to it, making it difficult to conclude exactly what happened. Firstly - the bits that make sense:

Signal loss is consistent with the terrain. If you compare the periods of signal loss with the computed viewshed then the results are as expected:

75715

The VPS height measurement does a pretty good job of detecting the stands of trees that the aircraft passes over, and these are as shown in the GE 3D rendering. The viewshed from around the 260 second mark is the green shaded area, and it's apparent how the trees are blocking line of sight.

75716

So that all makes reasonable sense. However, at the final point of signal loss, which should have triggered RTH, the aircraft was only 2140 m from the homepoint:

75717

Extrapolating the battery down to the autoland level at the heigh the aircraft was flying shows the following:

75718

In other words the aircraft had around 1100 seconds of flight left in the battery, which implies that it would have needed to make around 2 m/s (4.5 mph) into the wind to get back to the home point. Looking at the first graph above, it appears that the aircraft managed to hold position with a positive pitch of 10 - 13° at around 260 seconds - that should leave plenty of headroom for increasing pitch and making reasonable headway into the wind. For comparison, AirData's aerodynamic model suggests that the wind speed was 18 - 22 mph out of the NE for the latter part of this flight, which is also consistent.

But wait - there's more. Note from graphs 2 and 3 above that the smart battery level appears to stop decreasing after around 215 seconds. Looking at the actual cell voltages reveals an even more worrying feature:

75719

The cell voltages stop updating just after the start of the flight. That suggests that there is some kind of issue with the smart battery. That's previously been seen as a precursor to FC failure, could indicate that the battery is not properly seated, but possibly also means, presumably, since the battery level is stuck at 84%, that it will never autoland, and just drop out of the sky when the battery falls too low to keep it flying.

Another possible issue is that the trees towards the end of the recorded flight were fairly tall compared to the height of the aircraft. GE suggests that there was a clearance of 7 or 8 meters, which is somewhat confirmed by the VPS height data, but given barometer altitude variations and errors in the GE DEM tree heights then it's not inconceivable that it might have hit a treetop.

And there's even more. The takeoff point is actually within a DJI restricted zone on an extended runway path:

75722

If it did RTH then that would have caused it to land in the field on the left.

There's also the issue of the tall power lines:

75724

On the way out the aircraft flew under them. On the way back they look tall enough to have been a problem if the aircraft had ignored the restricted zone.

I'd take a look around the last recorded location (43.187878 N, 79.930683 W), the intersection of the RTH path with the powerlines, and the intersection of the RTH path with the restricted zone, but without any good evidence for whether this aircraft crashed, blew away, or tried to return home but didn't make it, this is a bit of a needle in a haystack.
 
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