Phantom3 Crash (ground station) lost altitude

It is 160 feet above the original point of take off. So if the terrain changes 100 feet higher at waypoint 1 from where you took off you now only have 60 feet clearance.
I understand your thinking and that could be it. BUT I have flown this exact mission at least 20 or more other times without issue. it is possible they were all close calls but I would hope that the software is smarter than that and is setting your altitude for each waypoint according to that gps coordinate. If they were the same why would that be a seperate setting for each waypoint. They could just have one.
 
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I gotta say, it looks more like the ground coming up than the Phantom coming down. Camera angle makes it tough to tell, though.
thats what my son said. so if thats the case it could be an imu failure. thats my thinking anyway. the data log file is uploading very slowly now.
 
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thats what my son said. so if thats the case it could be an imu failure. thats my thinking anyway. the data log file is uploading very slowly now.
How would the ground coming up be an imu failure?
 
I understand your thinking and that could be it. BUT I have flown this exact mission at least 20 or more other times without issue. it is possible they were all close calls but I would hope that the software is smarter than that and is setting your altitude for each waypoint according to that gps coordinate. If they were the same why would that be a seperate setting for each waypoint. They could just have one.
It's not my thinking. It is straight from the Litchi manual. Also keep in mind that the phantom determines its altitude based on barometric pressure rather than gps so it will not be perfect especially if you fly when the is different temperatures and pressure outside. Unless you are flying and the outside barometric pressure is the same and the temperature is the same every day the altitude will be off a bit. I attached a photo from the manual. Read the altitude section.
 

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It is 160 feet above the original point of take off. So if the terrain changes 100 feet higher at waypoint 1 from where you took off you now only have 60 feet clearance.
Thanks for confirming what would be the expected behavior. That's what I thought but I wasn't sure when I suggested it in my earlier post.

I think it is becoming clearer that the Phantom was likely just following orders and hit a tree due to the ground elevation change that was not accounted for when the mission was designed and executed.
 
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I understand your thinking and that could be it. BUT I have flown this exact mission at least 20 or more other times without issue. it is possible they were all close calls but I would hope that the software is smarter than that and is setting your altitude for each waypoint according to that gps coordinate. If they were the same why would that be a seperate setting for each waypoint. They could just hav
Thanks for confirming what would be the expected behavior. That's what I thought but I wasn't sure when I suggested it in my earlier post.

I think it is becoming clearer that the Phantom was likely just following orders and hit a tree due to the ground elevation change that was not accounted for when the mission was designed and executed.
No problem. Remember everybody, read the documentation for everything. It could save you a lot of headache and money.
 
For what its worth...
If terrain following flight plans is something you want to try, there is only one thing out there at present that does this, AFAIK.
Ground Station Software | UgCS PC Mission Planning
It's a bit different than the other options out there. It supports all kinds of drones from 3DR/Pixhawk to ParrotAR/Sensefly and a whole mess of boutique commercial UAV. They now also support P3/Inspire1. All planning is done with a PC, and there is a companion app that flies the drone. If you have the laptop and mobile device on the same wifi network, you have live planning and control of the drone from the laptop.

It also uses a geographical 3D database similar to Google Earth (but not the soon to disappear Google Earth API) for flight planning. Meaning that It does plan waypoints that are actually AGL (as opposed to AGL relative to the takeoff point). Further, if you try to plan a flight path that would otherwise go through a hill, it will adjust your plan to go over or around this obstruction. It does Litchi type photography/videography missions as well as survey grid type missions based on overlap and resolution/altitude.

It seems to have a pretty steep learning curve, and I've just started messing with it and haven't actually given it control of the P3 yet, so I can't speak to stability. The potential is great, though.
 
Should I change the extension?
No. You can only view DJI GO TXT or Litchi CSV files in my log viewer. You cannot upload a DAT file there -- if that's what you're trying to do.
 
No. You can only view DJI GO TXT or Litchi CSV files in my log viewer. You cannot upload a DAT file there -- if that's what you're trying to do.
ok it downloaded .dat so change extension to .txt?
 
this is like pulling teeth :-/
Haha... agreed :D

Unfortunately, changing the extension of a file does not change the contents of the file. Therefore, you still will not be able to use my log viewer after changing the file extension from DAT to TXT or CSV. You actually need to upload a DJI GO TXT log file or a Litchi CSV log file.
 
Haha... agreed :D

Unfortunately, changing the extension of a file does not change the contents of the file. Therefore, you still will not be able to use my log viewer after changing the file extension from DAT to TXT or CSV. You actually need to upload a DJI GO TXT log file or a Litchi CSV log file.
it didnt have contents that were .txt files only 2.84 gb of .dat
So%20far.png
 
Yep, those are definitely DAT files. Perhaps @happydays can assist. I'm not sure why he wants the DAT file.
 
Yep, those are definitely DAT files. Perhaps @happydays can assist. I'm not sure why he wants the DAT file.
the files on the android device would only show logs while its connected to the phantom. once connection is broken the logs on the android device cant really help much correct?
 
https://www.mapsmadeeasy.com/log_viewer this works

It currently only shows the the map of the flight path with a plot of altitude and velocity vs time but it is better than having all those sweet log files on your drone and not being able to do anything to do with them.
 
the files on the android device would only show logs while its connected to the phantom. once connection is broken the logs on the android device cant really help much correct?
Correct. Your connection wasn't broken before you crashed, so we'll be able to see the entire flight.
 
Sorry for the delay in replying. Different time zones!

Ok, if you can identify from the .DAT file which flight it refers to and send it to me via a drop box link or use wetransfer.com, I will run it through the converters and attempt to see what is going on. PM me if you need an email address.

I use a system developed by @BudWalker to convert the .DAT files into a readable format and then run it through the dashware system created by @Luap - so I can't take the credit for anything other than attempting to decipher the results.
 

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