Lost P4A

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At April 23 this year I lost my five month`s old P4A after lost signal from Satelites. In the flight rec. map I can see a trapes formed spot on sea level, in a possible flight direction. But the funnyest thing in the height during the flight, max are recorded to aprox 50 meters, --- BUT,-- in the recorded height at landing time,-- height are marked as minus 20 meter. I do not hear or see some of this, so I ask for a tip, what have happend. Impossible to think that my RC have recorded from minus 20 below sea level, ?? --or --??. Regards hsmP4A. (Norway)
 

Meta4

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At April 23 this year I lost my five month`s old P4A after lost signal from Satelites. In the flight rec. map I can see a trapes formed spot on sea level, in a possible flight direction. But the funnyest thing in the height during the flight, max are recorded to aprox 50 meters, --- BUT,-- in the recorded height at landing time,-- height are marked as minus 20 meter. I do not hear or see some of this, so I ask for a tip, what have happend. Impossible to think that my RC have recorded from minus 20 below sea level, ?? --or --??. Regards hsmP4A. (Norway)
It would help if you could post the flight record.
Negative heights usually indicate flying lower than the launch point but can also show after a crash that upsets the IMU sensors.
Post the data and it should be obvious.
 

msinger

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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.
 
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It would help if you could post the flight record.
Negative heights usually indicate flying lower than the launch point but can also show after a crash that upsets the IMU sensors.
Post the data and it should be obvious.
 
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During the flight, the weather was zero wind, beautyful sunset, the sea surface around the island Edoy was like a suncolored mirror, Beautyful evening, that ends not good. After that I got in contact with DJI, sendt the log, and the service team made a conclude, -- faulty elctronic in my P4A. I was lucky, got a new after short time. The new P4A have work every time !!!.
This are still in my head, where got the drone down to The Earth.
Regards hsmP4A. :D
 

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Have you edited that in anyway, if that is even possible?
There is one heck of a jump in the time stamps and height in the attached.
Around only 8% of the flight registered GPS satellites
 

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Hi. No, I have not do any edit in the recording. I see in the Lat- and Longitude, that point off flight-end are just close to where I made the lift-off. This point are in the middle of our lawn. The place for lift-off and registered "Home-point" are side by side. This look like a mess of position in registered startpoint and flight recording. When the drone start run-off, I follow up with my eyes, from in the height of 10 to 12 meter hoovering, and I made some camera adjustment, I registered the sound from propellers have a other direction. I look up, see the drone made a flight-direction allmost stright North, and have moved aprox- 20 meter. I have an previously flight like this, but I made a change in direction by the RC, and I got the drone back after a time. I than see, if I stop forced the RC in controlling, the drone goes by her self in wrong way, every time!. In the last run-off, nothing was able to help, and my eyes followed the drone until I lost it by distance. So---, why are the registered landed position just a fev meter from start point on the lawn ?.
regards hsmP4A
 

Meta4

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Link on my flight-record
You launched from a point about 22 metres above sea level, with the sea about 350-400 metres away to the south and east.
At 1:06.5 your GPS dropped out completely with the number of sats falling from 16 to zero instantly.
You acquired GPS again at 1:34.7 only to lose GPS again at 1:40.2
With no GPS and your drone in atti mode, there is no location data and no distance from home after 1:40.2.
You do some gentle control with the joysticks, taking the drone up to 50 metres but from 5:28.7 you leave the joysticks alone except for 1.5 seconds of right stick at 10:30.
It looks like you had full control as the drone responds properly when you gave joystick input.
The drone is still at 50 metres but and with full signal but will have been drifting on any wind.
At 14:39.6 you lose signal and the drone continues drifting.
Signal is regained after 8.2 minutes at 22:51.7.
When signal is regained, the Phantom is in Autolanding because it has reached critical low battery level.
The barometer is showing altitude as 20 metres below launch point and the VPS is showing the drone is 2.7 metres above something.
The altitude is steady and does not move until end of the flight record at 22:57.5.

We can't tell how far the drone drifted, in which direction or where it landed because GPS was lost for most of the flight.
We can tell that the drone came to rest somewhere 20 metres lower than the launch point and the VPS data suggests it might have been in a low tree about 2.7 metres above the ground or water.
 

sar104

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Hi. No, I have not do any edit in the recording. I see in the Lat- and Longitude, that point off flight-end are just close to where I made the lift-off. This point are in the middle of our lawn. The place for lift-off and registered "Home-point" are side by side. This look like a mess of position in registered startpoint and flight recording. When the drone start run-off, I follow up with my eyes, from in the height of 10 to 12 meter hoovering, and I made some camera adjustment, I registered the sound from propellers have a other direction. I look up, see the drone made a flight-direction allmost stright North, and have moved aprox- 20 meter. I have an previously flight like this, but I made a change in direction by the RC, and I got the drone back after a time. I than see, if I stop forced the RC in controlling, the drone goes by her self in wrong way, every time!. In the last run-off, nothing was able to help, and my eyes followed the drone until I lost it by distance. So---, why are the registered landed position just a fev meter from start point on the lawn ?.
regards hsmP4A
It's possible that there useable GPS data in the mobile device DAT file (FLY049.DAT), even though the aircraft was in ATTI mode. Probably worth a look if you can retrieve the file.

Mobile device DAT file: How to retrieve a V3.DAT from the tablet
 

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Have you edited that in anyway, if that is even possible?
There is one heck of a jump in the time stamps and height in the attached.
Around only 8% of the flight registered GPS satellites
Please correct me if I'm wrong, but that seems normal to me.

There was no data (download) being received from the Phantom. His mobile device was still logging, time is the only thing that is updated, until the download returned.

Rod
 
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You and Meta4 having 'mentioned' it makes it leap out at me as sort of obvious but the thought didn't occur at the time I asked the 'question'.
 
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msinger

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Please correct me if I'm wrong, but that seems normal to me.
Yes, that is normal since the downlink dropped. When that happens, DJI GO stops recording data in the TXT flight log.

As @sar104 pointed out, there is likely some additional data in the DAT flight log on the mobile device since the mobile device was still connected to the aircraft during that time.
 
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RodPad

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You and Meta4 having 'mentioned' it makes it leap out at me as sort of obvious but the thought didn't occur at the time I asked the 'question'.
Hum, I hadn't read it all, I also had jumped over that he got one replaced from DJI, that was going to be my next post, since it seemed to be a Fantom Phalure. :rolleyes:

The time delay from lost to his first post make sense now.

@msinger has already chimed in since I was speed typing.


@hsmP4A,
Welcome to the Forum!

See if you can dig up the file @sar104 asked for. ;)

I will let you take your thread back. :)

Rod
 
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Hi. Yes, I do understand that you have some question`s about my membership in this forum, and try to got info about a lost P4A, that service crew at DJI got a result for a failure in reseption of sat- lignal for this flight at April 23.
I have recording from the first time I got this P4, and the flight records are owerflowing with NO- sat-signal, No lift-off. Some situation`s end`s up with give it up, put all in the box and try a other day !!!!!.
Read my description when the first P4 try to run-off the first time, but I was lucky to keep the thing back on earth.
I attach the two .DAT files from April 23.
I hope to find the P4A, as the area at the North side of this island are a area for 500 sheep in open range.
Regards hsmP4A.
 

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sar104

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Hi. Yes, I do understand that you have some question`s about my membership in this forum, and try to got info about a lost P4A, that service crew at DJI got a result for a failure in reseption of sat- lignal for this flight at April 23.
I have recording from the first time I got this P4, and the flight records are owerflowing with NO- sat-signal, No lift-off. Some situation`s end`s up with give it up, put all in the box and try a other day !!!!!.
Read my description when the first P4 try to run-off the first time, but I was lucky to keep the thing back on earth.
I attach the two .DAT files from April 23.
I hope to find the P4A, as the area at the North side of this island are a area for 500 sheep in open range.
Regards hsmP4A.
Sorry - that one has gone. The last recorded point, at 880 seconds with a battery level of 43%, is as shown below, with the aircraft moving at 1.65 m/s (6 km/hr) northwest. In ATTI mode it will have commenced autolanding on loss of uplink. It's in the drink.

1568242734245.jpeg
 
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Hi.
I hope the flightrecorder have a chanse to give a pin-point where the wreck have to stay, but as I understand, -- the basic system have deep connection to satelite-signal. If - and when I try to find the drone, are like a small needle in a pile of hey. Many thank`s to You all, for help and information.
Regards hsmP4A.
 

sar104

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Hi.
I hope the flightrecorder have a chanse to give a pin-point where the wreck have to stay, but as I understand, -- the basic system have deep connection to satelite-signal. If - and when I try to find the drone, are like a small needle in a pile of hey. Many thank`s to You all, for help and information.
Regards hsmP4A.
Did you see my post above?
 
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Fly Dawg

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