Complete Signal Loss and Drone Didn't Return

[HalfLife88]

I just got a Phantom 4 for my birthday on Saturday, August 20, and now it seems to have decided to go into Phantom mode becuase it is gone. I launched the Phantom from a field about 1500 feet from my parents house and proceeded to fly it over their property at an altitude of about 125 feet. My signal got choppy but restored right as I got above their property and then when I started to descend the Phantom the signal dropped completely and never came back. According to my parents the drone went straight up for a few seconds, turned around, and then "hauled *** that-a-way". The direction they pointed in perfectly aligned with the Return To Home path the drone should've taken. Here is a screenshot of what I was seeing as what shoud've been the RTH path.



About 5 minutes after I lost the signal I started to drive towards my parents house because I assumed that if it had turned around to come back then I would've already seen it, or heard it. When I got there they told me the drone had flown away about 5 minutes before I arrived and that they thought I just flew it back to myself. The RTH height was set to 50 meters which is plenty high to clear all the trees and power lines in that area and my parents confirmed that it was well above all the trees when it went out of sight from there house. Welp... that was the last time anyone saw the drone. We drove up and down the road in the area looking, stopping to listen, and trying to see if the controller would reconnect. We went back to the home point and waited because I hoped that when the battery started to drain it would send itself home. No luck at all. I have absolutely no clue what to do next. We are planning to go trekking through the woods tomorrow when there is daylight. Is there anyway to see the GPS coordinates of the drone itself after I lost my connection? I'm still pretty baffled as why that data wouldn't be stored somewhere accessible to the people flying these things.

Here is the link to the flight log.

HealthyDrones.com - Innovative flight data analysis that matters

The reason it mode changed to GPS-Atti twice at the beginning was because I had to turn the controller off and then on again to get the camera feed to start. I realize that there is absolutely no information after the connection loss but from what I've seen on these forums people like to see the logs. Any suggestions anyone has would be much appreciated.

*edit - I changed it from saying my birthday yesterday to the actual date I received it

 

[msinger]

Please upload your TXT flight log here and post a link back here.

 

[HalfLife88]

Please upload your TXT flight log here and post a link back here.

Phantom Log Viewer - PhantomHelp.com

I'm not sure I did this correctly because I can't see that anything happened after the upload. I re downloaded the file from my iPad just to make sure I was using the right one and I got the same result.

 

[msinger]

You did it correctly. My log viewer is not able to read your log. And, unfortunately, Healthy Drones does not reveal much information about your flight.

Without being able to review the full log, I can only assume your Phantom crashed into one of the trees along red line below:

Your Phantom was at an altitude of about 90 feet when RTH was initiated (it could have been lower). I'm assuming it was RTHing since your parents saw it rise and then fly toward the home point.

Is it possible that the RTH altitude was really set to 30m (the default)? If so, it might not have been high enough to clear the trees.

 

[HalfLife88]

I remember setting the RTH altitude to 50m on Saturday -the day before the flight we are discussing- so unless it defaulted at the beginning of the flight it was still at 50m. Even at 30m it should've cleared all the trees in that area because most of them stand around 80-90 feet tall max. The middle of that section of trees has an area where the terrain creates a bit of a valley but nothing to significant, and the top of tree line is uniform. According to the people who saw it fly off it had plenty of clearance above the trees so if it did start to descend where the ground began to drop wouldn't the sensors pick up the tree tops because it was in P mode?

BTW thank you for your quick replies as I really do appreciate it.

Do you have any idea what if either of these scenarios is covered by DJI?
1) drone entered RTH but for some reason went off course and I don't find it
2) drone RTH'd and descended itself into a set of trees and crashed

I just got off work so I'm about to go back out on the hunt.

 

[msinger]

I remember setting the RTH altitude to 50m on Saturday -the day before the flight we are discussing

Was your Phantom connected to DJI GO at the time? If not, the setting was not actually saved.

Even at 30m it should've cleared all the trees in that area because most of them stand around 80-90 feet tall max.

The altitude displayed by your Phantom is not always dead on. It's not uncommon for it to be off by up to ~20 feet.

if it did start to descend where the ground began to drop wouldn't the sensors pick up the tree tops because it was in P mode?

If you had that feature enabled in DJI GO, your Phantom should have stopped and ascended further if there was an obstacle in its path while it was flying back to the home point. The sensors would not be able to pick up power lines though.

Do you have any idea what if either of these scenarios is covered by DJI?

DJI would likely partially/fully cover any instances of technical failure on their end. Crashes are commonly caused by user error though. They would decide how to proceed based on what your flight log revealed.

 

[clickclickw00t]

I've heard many reports of RTH altitude resetting or changing after putting a new battery in, or not being connected to the bird/controller properly. I would say it is a mandatory as a pre-flight check to check your RTH height.

 

[msinger]

I've heard many reports of RTH altitude resetting or changing after putting a new battery in

Got a link?

Ior not being connected to the bird/controller properly

That's working as designed. If the setting is stored on the Phantom (e.g. RTH Altitude), DJI GO must be connected to the Phantom while changing the setting.

 

[clickclickw00t]

Got a link?


That's working as designed. If the setting is stored on the Phantom (e.g. RTH Altitude), DJI GO must be connected to the Phantom while changing the setting.

Let me rephrase, it was probably 2 or 3 posts that I read. Must be split between here, the DJI reddit page, a few Phantom 4 groups on Facebook, and RcPilot. One poster specifically stated that he set his RTH to 50m, discharged battery, charged battery, inserted battery into Phantom, and the RTH was reset to 30m.

 

[clickclickw00t]

Then again, this could ALL be user error. Hard to trust what people say online.

 

[msinger]

Yep -- I'm betting user error on that one. Other than when installing new firmware, I've never heard of the RTH Altitude auto resetting.

 

[HalfLife88]

Was your Phantom connected to DJI GO at the time? If not, the setting was not actually saved.


If you had that feature enabled in DJI GO, your Phantom should have stopped and ascended further if there was an obstacle in its path while it was flying back to the home point. The sensors would not be able to pick up power lines though.

DJI would likely partially/fully cover any instances of technical failure on their end. Crashes are commonly caused by user error though. They would decide how to proceed based on what your flight log revealed.

Yeah I got about 10 flights in before the fatal flight and never went without DJI GO. The only power lines in my area are about half the height of the trees so I don't believe they would've been an issue

Yeah and I'm sure user error is not clearly defined in these cases. I don't feel like I did anything blatantly wrong, but I'm also both new and biased. I do feel like in this situation it is reasonable to believe the drone should've been able to safely navigate back to the home point given that it began with no obstructions above or in front of it .

 

[HalfLife88]

Then again, this could ALL be user error. Hard to trust what people say online.

Lol. What do I have to gain by starting a forum to lie about what happened?

 

[JEHoover]

Ugh. I wish I could offer some help, but wish you the best of luck. Just ordered the Phantom 4 yesterday.

 

[HalfLife88]

Ugh. I wish I could offer some help, but wish you the best of luck. Just ordered the Phantom 4 yesterday.

It was insanely fun while it lasted! I have a replace ticket in with DJI so I'll wait to hear back from them. I just walked through the woods again along the line that msinger suggested and came up empty. I'm not convinced it wouldn't have stayed in the top of the tree if it did descend into them

 

[clickclickw00t]

Lol. What do I have to gain by starting a forum to lie about what happened?

Not you! I'm talking about other reports of flyaways...


Sent from my iPad using PhantomPilots

 

[HalfLife88]

Not you! I'm talking about other reports of flyaways...


Sent from my iPad using PhantomPilots

Fair enough. Yeah I'm always skeptical of things online which is why I try to provide as much detail as I can.

 

[HalfLife88]

FOUND IT!! That's about the only good news I have. I went back through the woods again before it got dark last night and I found it laying props down with the battery sitting about 10 feet away. It wasn't far off of msinger's line at all which means I either walked right by it on the previous walk or it blew out of the top of a tree. I marked the area I found it in on the pic below. I'm still confused as to how it managed to clear 95% of the trees that were the same height as the ones in the area where it came down.

And here is the damage:

Broke prop and nasty gash on the rear left part of the body.



Busted Gimbal assembly


And the battery still worked but the third LED isn't lighting up.


I put the battery back in and turned it on. It went through it's full initialization sequence and actually gave me a Safe to Fly (GPS) on the DJI Go App. The only error it gave was that there was a hardware malfunction with the camera. I was hoping the flight log would update so I could see the logs after I lost my connection, but I had no such luck. So I'm hoping I get out of this one with a new body and gimbal assembly. I still have a set of spare props. It's boxed up and heading to DJI today.

 

[neven]

FOUND IT!! That's about the only good news I have. I went back through the woods again before it got dark last night and I found it laying props down with the battery sitting about 10 feet away. It wasn't far off of msinger's line at all which means I either walked right by it on the previous walk or it blew out of the top of a tree. I marked the area I found it in on the pic below. I'm still confused as to how it managed to clear 95% of the trees that were the same height as the ones in the area where it came down.

View attachment 62967

And here is the damage:

Broke prop and nasty gash on the rear left part of the body.
View attachment 62972


Busted Gimbal assembly
View attachment 62974

And the battery still worked but the third LED isn't lighting up.
View attachment 62973

I put the battery back in and turned it on. It went through it's full initialization sequence and actually gave me a Safe to Fly (GPS) on the DJI Go App. The only error it gave was that there was a hardware malfunction with the camera. I was hoping the flight log would update so I could see the logs after I lost my connection, but I had no such luck. So I'm hoping I get out of this one with a new body and gimbal assembly. I still have a set of spare props. It's boxed up and heading to DJI today.

Download .dat file from Phantom before sending it to DJI. That is a real black box material.

 

[r62ewa]

Chalk another successful recovery up to msinger, if anything ever happens to mine he's getting a PM immediately! RTH height is critical to check before each flight. I have been using Pix4D Capture App and when I set the height in that App it changes my Maximum altitude flight height in the Go App. I didn't know that and my complacency almost caused me a crash as well, now I check it religiously.