P4 Advanced Authorization Zone Mid Flight & Compass Error

Locking the drone whilst already in flight is totally unacceptable, operator must always retain control
Agreed. I don't think the OP was locked out though. It seems he stopped attempting to control his Phantom and focused solely on getting an authorization unlock code. Meanwhile, his Phantom drifted away in the wind.
 
Locking the drone whilst already in flight is totally unacceptable, operator must always retain control, no warning or token request should override control, not ever, not never.

After some analyzation the drone may not have been locked but may have had the appearance of being locked. Going to do further testing asap.
 
Same happened to me with my phantom 4 original i had no control lucky me that the drone went to a parking lot and stayed hover so i just went there and graved it
 
I use this iPhone app to check for Magnetic Interference before attempting a compass calibration;
Teslameter 11th: Pro Metal Detector on the App Store
Why are people wanting to calibrate their compass so often?
I still haven't calibrated the compass of the P4 pro that I got 9 months ago.
Here's what your manual recommends:
i-Q9CJx8r-M.jpg
 
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Why are people wanting to calibrate their compass so often?
I still haven't calibrated the compass of the P4 pro that I got 9 months ago.
Here's what your manual recommends:
i-Q9CJx8r-M.jpg

Agreed, have a Phantom 3 standard here and I have not calibrated mine in months as well. It make the compass unstable doing too many unnecessary calibrations.
 
Agreed, have a Phantom 3 standard here and I have not calibrated mine in months as well. It make the compass unstable doing too many unnecessary calibrations.
It doesn't make the compass unstable but each time, you risk getting a bad calibration.
Since it's completely unnecessary, that's a risk you don't need to take.
 
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This has been an interesting read, so I have to throw in my two cents in here. Sorry for the length.

I agree with @msinger. It appears the OP was distracted by the Go4 app dialog, telling the pilot he lost control (which he then assumed), and the app telling him it's taking the drone away to its home point, which was false, because it can't when the craft is in ATTI. The wind was taking it away, which the OP thought was the app taking it away. With all the distraction of trying to get a token, then disconnecting the USB cord and restarting the app (thinking that would solve the problem, as in his past), that all takes time, and during this precious time the craft was in ATTI mode (but pilot said he didn't know it was in ATTI mode at the time) because of a compass error. As a result, during all this time, the craft drifted in the wind, eventually behind something or far enough to lose connection, gone bye bye (really sorry for the loss). In an effort to be productive, here are some points which came to mind that may have been able to prevent this loss of craft, and one that should be SOP:

1. The app or tablet does not to be connected or running to fly and control the drone with the RC, assuming you have VLOS. The RC alone can control the drone, no app or tablet needed if you have VLOS.
2. If you loose compass functionality (GPS mismatch) the craft has NO WAY to find it's way to home. RTH can't work without a compass, regardless how many satellites you have connected.
3. You cannot claim to be experienced at flying DJI craft if you don't know how to fly in ATTI. This is an essential skill for emergencies, and it's not that difficult to learn.
4. If you think your craft is acting weird, doing things that your sticks don't match during P or S mode, you should switch to ATTI and navigate straight home to resolve the issue, either via FPV or VLOS. Unfortunately many are afraid of ATTI and avoid this option like the plague.
5. Always fly with your antenna's up, and as SOP, avoid flying directly overhead where the signal is weakest when the RC antennas are vertical. (No, I'm not saying this has anything to do with this loss). I would never ascend straight up 200', but that's me. Forget being polite with noise and do the right thing to protect the flight integrity.
6. ATTI mode maintains only altitude, using the barometer. The craft WILL DRIFT with the wind in ATTI mode if you don't give it stick input to control it. YOU CAN DECEND with the left stick, like normal, and you can control speed and direction.
7. Never get distracted to the point of not watching your craft for more than a couple seconds, either VLOS or FPV. It's like driving a car, don't take your eyes off the road for more than a couple seconds, right? The first priority is keep tract of your craft, where it is, what it's doing. Other distractions are secondary. This is key when doing other things while flying like setting camera settings, setting home point, loading a Litchi mission, or obtaining a token for flying rights. I will usually watch my display view to insure the craft isn't moving while adjusting settings, easily done simultaneously with peripheral vision.

In this case, I believe the OP assumed he didn't have control of the craft, when he did via ATTI. He didn't try to bring the craft back when it initially started drifting, thinking he cannot regain control until the app gave him control by obtaining a token (this assumption being the root problem). All that time the craft was drifting away in ATTI, and by the time he tried to use the sticks, it was out of range. Granted, I wasn't there, but that's what I believed happened, based on what I've read in this thread and flight log.

I am curious why the OP didn't know the craft was in ATTI mode. Usually the app will say ATTI mode when a compass errors happens, am I wrong? I admit I have never seen compass error with P4 or P4P (dual compass). My only experience of this is kind of event was with my P3P, when I got an ATTI dialog during a compass error, and that was over a year ago. I'm thinking maybe this new distraction of getting a token in a NFZ replaced the ATTI announcement in the app. IMO, it's essential to know you're in ATTI when that happens. ATTI mode needs to be obvious IMO. Did they take the ATTI announcement out during compass error events, or during NFZ events?

If a craft disobeys stick input and flies arbitrarily, in a deliberate way, that's called a fly away. Bit since P3P's release with Lightbridge, there have been very few actual cases of this, too few to be concerned about. If the craft slowly drifts in the direction of the wind without stick commands, this is usually ATTI, but you should still have manual nav control when pilot engages with the sticks. If the craft doesn't obey stick commands, such as descend with left stick, and no direction control, then you have a fly away, but that's extremely rare. In my mind fly-aways are impossible with Lightbridge, but hardware can fail, anything is possible.

Many times if the craft is far away, when flying VLOS, you cannot discern which way the craft is pointed and get disoriented when trying to navigate. However, in an emergency, if you give the craft a descend command, you can easily determine if you have nav control of the craft. If it descends, you will clearly see it descend VLOS without any confusion or disorientation. Then it's a matter of calmly getting yourself oriented via VLOS, or via FPV assuming you have a video connection. If flying VLOS, just be careful you don't fly away from you when you think you are flying toward you (easy to do). If it's 1000' away it's just a dot in the sky. Use the radar screen to determine craft orientation, assuming the radar is working with a compass error. If using VLOS to navigate, fly slow in a right hand circle to get oriented with navigation, confirming which way the craft is pointed. But if I have an FPV connection or radar, it's usually easier and safer to fly home via FPV with radar confirmation.

I definitely agree with the OP's opinion that the craft should never have been allowed to take-off in the first place if a token was needed at the launch point, that's common sense. This determination should be done with the craft firmware, not the Go4 app software, allowing this decision process to work QUICK, regardless of cell connection. Does anyone know how that works? If this NFZ policing is done through the app via cellular connection (gee I hope not), the OP's tablet may not have had a good cell signal, or the DJI computers were too slow to catch this before take-off. Regardless, I think the tardy token requirement in a NFZ could be a flaw that needs to be improved.
 
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If you can see the AC, even if it is small, you can determine the direction it is facing, by slipping left and right. If you go right and it goes left, it is facing you. This will help to get it heading in the right direction, once it is close enough, you can determine this visually.
 
If you can see the AC, even if it is small, you can determine the direction it is facing, by slipping left and right. If you go right and it goes left, it is facing you. This will help to get it heading in the right direction, once it is close enough, you can determine this visually.
Yes, that works if your craft's flight direction isn't perpendicular to the pilot direction. I find a small circle works better.
 
This has been an interesting read, so I have to throw in my two cents in here. Sorry for the length.

I agree with @msinger. It appears the OP was distracted by the Go4 app dialog, telling the pilot he lost control (which he then assumed), and the app telling him it's taking the drone away to its home point, which was false, because it can't when the craft is in ATTI. The wind was taking it away, which the OP thought was the app taking it away. With all the distraction of trying to get a token, then disconnecting the USB cord and restarting the app (thinking that would solve the problem, as in his past), that all takes time, and during this precious time the craft was in ATTI mode (but pilot said he didn't know it was in ATTI mode at the time) because of a compass error. As a result, during all this time, the craft drifted in the wind, eventually behind something or far enough to lose connection, gone bye bye (really sorry for the loss). In an effort to be productive, here are some points which came to mind that may have been able to prevent this loss of craft, and one that should be SOP:

John, your analysis is quite accurate. The main issue was with the Auth Zone message. It took over the entire screen and was extremely distracting. It should have been a small warning message, especially if the craft was already in flight. I can and have flown in ATTI mode plenty of times but I was not aware that it was in ATTI due to the distraction of obtaining the token. Also, since I placed the craft at 200 feet I could no longer hear it. I did have a spotter but they were about 400 feet on the other corner of the building and they probably assumed that I was flying the craft normally so they didn't say anything until it was too late. I obviously did not touch the control sticks at all before it lost connection which happened a little over a minute into flight. The first 15-20 seconds we're under my control in the ascent and during that time the message came up, which I dealt with for about a minute, and then it was too late. My assumption was that the craft was still in GPS mode locked in directly over me and I did not verify because I thought the spotter was my safety net. I forgot to realize that they wouldn't be able to tell the difference between a drift and me flying the craft.

It was a perfect scenario of multiple things going wrong. The compass error, the radio interference in the area causing it to disconnect earlier than it should have, the wind drift, the auth zone process of obtaining a token and its appearance of taking over the screen completely and the misleading messages that the aircraft was being "taken over and RTH" automatically. That action was probably cancelled due to the compass errors / ATTI model which may have kicked in during ascent prior to RTH being able to activate. And I know that is the default behavior due to other users on the Internet reporting as such. I was essentially tricked into thinking that obtaining a token was the first priority before any other action.

I do believe in further enhancing of airspace rules and geo fencing to accommodate the influx of UAVs but I don't believe that DJI should think its software is the end all be all and take over someone's screen while in flight. The operator should always be the determinator of where the UAV actually is in relation to airspace boundaries and safe flight.
 
Yes, that works if your craft's flight direction isn't perpendicular to the pilot direction. I find a small circle works better.
I figured, if it is going left or right, with forward stick, you know it's not going away or coming at you. Usually disorientation happens when it comes towards you, in my experience.
 
Best way to determine the connection status to the aircraft is to check the normally green LED on the RC to the left of the four white battery indicator LED's. If it has turned from green (connected) to red, you are disconnected from the aircraft, and cannot control it until the LED returns to green. As long as it is still green, you are still fully connected to the aircraft and the RC is still fully in control. Use it!
 
Hey if msinger has seen your logs and explained to you what happened in them you can pretty much take that to the bank,,,, that being said I’m very sorry for your loss,,, sh_t happens live and learn my friend!!! A lot of us have been flying for many years before without the aid of gps etc... maybe next Drone practice in Atti mode for a few months! You can still know where you are by watching your elevation and heading!! Pilot error is a ***** but you learn! I’m sure we all have!!! Best of luck on your next one!
 
Agreed. I don't think the OP was locked out though. It seems he stopped attempting to control his Phantom and focused solely on getting an authorization unlock code. Meanwhile, his Phantom drifted away in the wind.

I agree, there were no stick inputs after reaching 200-210’ and the bird being in Atti mode just drifted away. End of story! BUT I’m very sure if the OP followed the flight path with a few friends he could probably find the bird. It could have only gone so far!
 

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