Yeah! Second drone is gone... In the river.. Totally mystic!! I lost signal from drone P3P less than a minute after start. Flight distance was only 600m, altitude 21m...no return home, just signal loss. Battery fully charged, software updated.. I have no idea what happened.

Do you know what your setting were?
Fail safe RTH, was this enabled?

did you SEE what happened to it ...
or was it out of site?

It was out of sight. RTH was enabled, previously it worked well. Now nothing. After alert appear i tried to increase altitude, but drone did not response.. Later i got anither drone to find my bird, but we did not see it under water. Water is clear and shallow, but fast..

River? 21m altitude?

Were there any trees around by chance?

River is wide, and flight was by the center axis of river. No trees, absolutely sure...

shauttra Posted at 2016-6-4 02:20
River is wide, and flight was by the center axis of river. No trees, absolutely sure...

Without a good description of what hapened and some flight data, all anyone can do is make guesses that are most likely wrong.
Your app has a "black box" data recorder that can probably explain what happened.

Go to http://www.phantomhelp.com/LogViewer/Upload/
Follow the instructions to upload your flight record.

Come back and post a link to the report it provides and some of the experienced people here will probably be able to analyse it and give you an understanding of the cause of the incident and perhaps point you to a likely area to search for the Phantom.

Soundslike a good candidate for a potential bird strike

Cessna172 Posted at 2016-6-3 19:10
Soundslike a good candidate for a potential bird strike

Man I scared to fly at beach due to stupid seagulls, I have had a few birds fly to it and noise dive at the last minute.  

Phantom is prone to bird attacks

Leaping lizards, flying fish, angry anaconda, but all kidding aside, a bird strike would be very likely there.
Over twenty thousand white storks and at least a thousand black storks nest in Latvia. Folk songs revere the bird as a sacred symbol of fertility and luck.
But perhaps not so lucky for you, if you fly over a fertile breeding/nesting area of water. Oh sure you got screwed, but in all the wrong possible meanings. ;-)

You need to hire someone familiar with underwater selvage to go down in wetsuit and bring your drowned drone back from the drink. Ha
If you're a truly lucky Latvian, it may have sunk straight down to the bottom, where it rests in its watery grave, waiting for retrieval.

RedHotPoker

RedHotPoker Posted at 2016-6-4 13:26
Leaping lizards, flying fish, angry anaconda, but all kidding aside, a bird strike would be very lik ...

'Folk songs revere the bird as a sacred symbol of fertility and luck.'

Are you saying a Stork tried to boogie with the Phantom?

Oh yeah! Whit storks are on every corner. But this river part is close to city and is used for recreation purposes, lot of hiking tracks. No storks here, only some goosander with new generation.
Last what i saw in App screen was nice view of river cliff. Image was clear. In case of bird strike there must be some noticeable effect of impact.
I uploaded flight data, and there is one suspicious thing no home point was recorded!! Only RTH altitude 30m. It was second flight in that morning and at first flight home point was recorded. Home point recording happens automatically, just before take off.
One more interesting thing - in previous flight there was data loss for 4.2sec at distance 310m alt18m.

shauttra Posted at 2016-6-4 18:33
Oh yeah! Whit storks are on every corner. But this river part is close to city and is used for recre ...

Where's the flight data?
Are you sure that home point wasn't recorded?

Yes, there is no info about home point, also altitude on the ground is dropping under zero, GPS satellites was 15+

shauttra Posted at 2016-6-4 18:57
Yes, there is no info about home point, also altitude on the ground is dropping under zero, GPS sate ...

Are you going to share the flight data or keep it to yourself?

There is a link, not enough expierence with data sharing
http://healthydrones.com/main?share=YldNzx

shauttra Posted at 2016-6-4 19:11
There is a link, not enough expierence with data sharing
http://healthydrones.com/main?share=YldN ...

HealthyDrones only gives a basic summary without real data.
If you can try the link I provided above, I can probably work things out.
http://forum.dji.com/forum.php?m ... 3&fromuid=10818

But for a start, I can see that your Phantom did record a home point.

labroides@yahoo Posted at 2016-6-4 19:19
HealthyDrones only gives a basic summary without real data.
If you can try the link I provided abo ...

It looks like you flew behind terrain and lost signal.
I'll be able to tell more if you can supply PhantomHelp data.

Ok, there is another data
http://www.phantomhelp.com/LogViewer/56LD2ZTZ0HF31PDPME2H/

shauttra Posted at 2016-6-4 10:32
Ok, there is another data
http://www.phantomhelp.com/LogViewer/56LD2ZTZ0HF31PDPME2H/

How tall are the trees on the river bank? Greater than 30M?
Maybe lost signal, then RTH at 30m but not high enough to clear the trees which are on the direct route back to home.

richmars Posted at 2016-6-4 12:58
How tall are the trees on the river bank? Greater than 30M?
Maybe lost signal, then RTH at 30m but ...

I thought about that, but i took off aircraft from a bank, which is about 4-5m above water level+flight altitude 21m. I was at almost highest point. At the beginning of flight i must fly over few trees to reach river, and it was done in safe height. But anyway there should be some data about returning home, or reaching RTH altitude or changing flight direction..

shauttra Posted at 2016-6-4 20:06
I thought about that, but i took off aircraft from a bank, which is about 4-5m above water level+f ...

Here's my assessment:

Home recorded        57.53282  25.44287
Home altitude        37 m (close to river level)
RTH                       30m
Terrain height        50 metres + trees
Phantom altitude            21 m
        
The Phantom was flown along the river and around a bend.
As the Phantom went around the bend, terrain on the far bank of the river blocked signal at 55 seconds but signal was restored after 1 second.  The Phantom was able to communicate with the controller because of a small gap in the terrain but 8 metres further on, signal was lost completely.
After 3 seconds the Phantom would have initiated RTH.  There is no record of RTH because signal from the Phantom was blocked by terrain + trees.

It would have climbed 9 m to RTH height of 30 m above Home.  This would have put it approximately 17 metres above Google Earth terrain height plus tree height.  If there were trees >17 metres high on the RTH route or if Google Earth height is slightly less than actual height, the Phantom would have crashed into a tree close to the river bank.

Flying out of sight behind terrain is a risky thing to do.
RTH height was not enough to clear the trees

Wow! So there is a hope to find it!
I am on the way to serch it again!
Really great thanks!!!!!

shauttra Posted at 2016-6-4 11:21
Wow! So there is a hope to find it!
I am on the way to serch it again!
Really great thanks!!!!!  ...

That's may reading of the data as well. Don't forget RTH is pretty dumb. It doesn't retrace it's path (maybe it should?)

richmars Posted at 2016-6-4 20:47
That's may reading of the data as well. Don't forget RTH is pretty dumb. It doesn't retrace it's p ...

Sometimes retracing would be helpful, many times though, it wouldn't  
(think low battery when close to home ... retracing a long path wouldn't be good).
Having options would be too complicated and catch people out.
The simplest RTH solution is what we have.
No confusion ... just set it high enough to clear obstacles.

Yes, i was absolutely shure that height is enough for RTH, because at take off i allready flight above trees, and i was higher than opposite bank.

shauttra Posted at 2016-6-3 12:20
River is wide, and flight was by the center axis of river. No trees, absolutely sure...

If it went onto the drink it is probably history anyway. Sorry for your loss.

shauttra Posted at 2016-6-3 09:20
River is wide, and flight was by the center axis of river. No trees, absolutely sure...

I see many trees.

Annnnnnd, this is a great exercise in why NOT to fly the drone out of your sight and fly line of sight ONLY.

185EZ Posted at 2016-6-4 15:33
I see many trees.

No trees in flight direction, river is at least 150m wide.

Geebax Posted at 2016-6-3 23:37
'Folk songs revere the bird as a sacred symbol of fertility and luck.'

Are you saying a Stork tri ...

Did I say the magic word? Hahaha
I tried my best to refrain from being vulgar...

Yes, the bird tried to make out with the drone. Cross breeding.

RedHotPoker

Labroides, I love your analytical ability.  I've read several of them and this one is right up there.  If I ever have a true mystery, I'm going to come calling!

Shauttra, my reading of the tree situation was that you could not see the drone because of the trees.  That also means the signal was greatly attenuated by the trees.  Trees contain moisture.  Moisture and other high density materials BLOCK short wavelength RF signals, such as used for control and telemetry.  Also, your RTH altitude is quite low for where you were flying.  It should be set to clear any obstacle in any direction from you within any practical range.  It should not just clear, but be in excess of clearing by a good margin.  (Not just in the direction you are going to be flying, because if things go wrong, it may go where you don't want it to go.)  Anytime you are going to fly around trees, especially with the density of a forest, you should be sure to maintain at least visual sight of the drone, and never let it drop so low that you can't see it because of the trees.  If you need to fly low, you need to go to that location, so you (and the radio) can see and maintain control.

RedHotPoker Posted at 2016-6-5 04:18
Did I say the magic word? Hahaha
I tried my best to refrain from being vulgar...

I would not mind if I could get a little baby P4......

You mean the Drone Baby Phantom?
http://www.xavdrone.com/drone-baby-phantom/

RedHotPoker

labroides@yahoo Posted at 2016-6-4 04:15
Here's my assessment:

Home recorded        57.53282  25.44287

Looking at that map overlay, it should be easy to find. Providing someone else hasn't happened upon its comfortable hiding place already.

RedHotPoker

Searching operation is done without results. Probably someone took it, because it is a forest type park, lot of humanoids are walking there...

labroides@yahoo Posted at 2016-6-4 20:15
Here's my assessment:

Home recorded        57.53282  25.44287

just out of curiosity - how did you create this? looks very good.


as for OP, sorry for your loss, i have crashed (my fault although just circumstance) a P3S, but had a RTH failure on my P3A on first flight.  DJI came the party somewhat to help but it was about the time the P4 was coming out so the price on the P3A drone only dropped beyond the discount they were giving.

DaveReidPhoto Posted at 2016-6-5 22:33
just out of curiosity - how did you create this? looks very good.

Thanks ... just look at the data as. displayed by PhantomHelp and the flight path from Google Earth

Try giving DJI a call, it can't hunt