Complete Signal Loss and Drone Didn't Return

HalfLife88 · Aug 23, 2016

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

How do I do that. I plugged the Phantom directly into my laptop and the only thing I could find was the SD card.

HalfLife88 · Aug 23, 2016

r62ewa said:
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.

Oh I can assure you that in the future I'll never take off without being sure that my RTH height is 500 meters... OK maybe not 500 meters but you get the point.

r62ewa · Aug 23, 2016

Something I don't know the answer to for sure, but can your RTH height be set higher than you maximum flight altitude? Or will the RTH altitude adhere to the maximum flight altitude?

msinger · Aug 23, 2016

HalfLife88 said:
How do I do that. I plugged the Phantom directly into my laptop and the only thing I could find was the SD card.

You can find instructions here. I don't know of any tools that can read it yet.

JEHoover · Aug 23, 2016

Great news that you found it. Congrats

neven · Aug 23, 2016

msinger said:
You can find instructions here. DatCon will not be able to read the DAT log though. I don't know of any tools that can read it yet.

I was not aware of this. So DJI made some major changes to .dat and not just adding extra sensor data? Or new data makes it so much more complex that our forum geniuses need bit more time to decypher it?

Sent from my iPhone using PhantomPilots

Pharm · Aug 23, 2016

Before you send it back, fire it up and see what your RTH altitude is.

msinger · Aug 23, 2016

neven said:
or new data makes it so much more complex that our forum geniuses need bit more time to decypher it?

This.

clickclickw00t · Aug 23, 2016

Pharm said:
Before you send it back, fire it up and see what your RTH altitude is.

I would be interested to know this as well!

Flintstone · Aug 27, 2016

HalfLife88 said:
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.

Did it hit a tree or did it just crash to the ground? I am wondering if the area around the crash sight is a clearing or did it hit a tree then fall to the ground? I have a P2V+ that had a bad battery and went into auto land mode and landed in a small bush no damage but I have 2 types of camera guards attached..... highly recommend guards for camera.

tribar · Aug 27, 2016

msinger said:
You can find instructions here. DatCon will not be able to read the DAT log though. I don't know of any tools that can read it yet.

This does not work for the P4, you need "DJI Assistant 2".
You can download it from their site:
DJI Phantom 4 – Specs, FAQ, Tutorials and Downloads

Kaitlyn · Aug 28, 2016

Stupid question - why does RTH height matter now that it has the "smart RTH" which includes obstacle avoidance?

msinger · Aug 28, 2016

Kaitlyn said:
why does RTH height matter now that it has the "smart RTH" which includes obstacle avoidance?

You could have obstacle avoidance turned off or the objects might be too small for the sensors to detect.

wassala! · Aug 28, 2016

Please let us all know what the data logs says

W la figa

Phillip LaRose · Aug 29, 2016

HalfLife88 said:
Oh I can assure you that in the future I'll never take off without being sure that my RTH height is 500 meters... OK maybe not 500 meters but you get the point.

Glad you found it. From my own experience I have found that judging altitude from the home point can be tricky. My property has a slope to it. If I set the home point at the front of the property, the slope can add 30 feet of altitude at the back. When I first started flying, I would set the RTH height well above the maximum tree height for my area. What I did not realize was that the tree could be sitting on a slope or an elevation above my home point. Fortunately I was flying
some tests up in my field when I found this out. I hope you get your Phantom repaired quickly and get back in the air.

RémyHeli · Aug 31, 2016

While flying, barometer acuracy - ie altitude reading - might suffer of ´distortion', so at some point the craft might think being higher or lower than reality. Seems worse with last firmware version and causing issues to RTH as relying on it.

For me two accumulated issues;
- Disconnect
- RTH

If not environmental electric, magnetic, gps, etc., did you deploy RC antennas correctly?

Just an idea, weird such disconnect didn't recover..

Sent from my iPhone using PhantomPilots mobile app

Pogopilot · Aug 31, 2016

r62ewa said:
Chalk another successful recovery up to msinger, if anything ever happens to mine he's getting a PM immediately!

Yup, Msinger saves another bird. Ihope to never loose mine, but if I do............ I know who I'm gona call. Great work Msinger

Dave Aespl · Aug 31, 2016

Only my third flight today,on second flight I raised the RTH altitude to 50 whilst flying over a dam I engaged RTH at about 30 m P4 started to descend cancelled RTH and landed, checked RTH alt
it was set for 5 m.Oops finger problems on I phone six small screen .Think I need something bigger, The answer to all novices fears of crashing or losing their drone is easily solved. Flexi rent it for the first year.Their drone is covered for all accidental damage as well as theft. Best policy I have seen. So glad you found yours! Tuff little sucker eh!

Pharm · Aug 31, 2016

RTH shouldn't descend at all. If you're flying lower than the RTH, it'll ascend to the RTH altitude. If it's higher than the RTH altitude, it'll return at the current altitude rather than descending.

ussvertigo · Sep 1, 2016

I bet you could straighten that arm best you can, nothing in the arm but wires to motors, buy new camera/gimbal, props, battery and she'll fly again (fingers cross) Cheapest option anyway