Let's discuss the issue of the sudden loss of GPS signal for a moment. GPS signal strength is typically represented by 5 bars in two ways, empty bars, and full bars.



In the example above, there are 5 "empty" bars and 2 "full" bars.

Empty bars are the GPS receiver's way of representing it's locked onto enough satellite signals to represent 5 bars. Generally, a GPS receiver needs 4 satellite signals to determine a 3-D representation of your location. The more satellite signals the GPS receiver is locked on to the better accuracy.

In order for the GPS receiver to display a full bar, it needs to download the detailed ephemeris data to determine the exact location of the satellite. Once orbit data has been downloaded then the GPS receiver represents this as full bars.

What would cause the GPS receiver on the Spark, in an instance, to change from 13 satellites, 4 full bars, and 5 empty bars to 12 satellites, 0 full bars, and 5 empty bars? What happened to the downloaded detailed ephemeris data represented by 4 full bars?

This doesn't appear to be a signal issue, the Spark GPS receiver is still locked onto 12 satellites in this example. What is happening to ALL ephemeris (orbit) data downloaded and downloading to the Spark? Any ideas? Heat? Load? Resonance? Intermodulation interference? Aliens?

I had no idea that GPS satellites gave you a 3D position, I always thought it was just Lat/Lon data and Time, with more Satellites making it more accurate.

Grmachine Posted at 2018-2-12 16:29
I had no idea that GPS satellites gave you a 3D position, I always thought it was just Lat/Lon data and Time, with more Satellites making it more accurate.

Supposedly you need 3 coordinates plus time.

In most instances I have seen where it is locked onto a sufficient number of satellites (12 in your example) and GPS goes to 0 bars is not that the GPS data is bad or its not getting a signal, but instead it is because of a Compass or Yaw error and the DJI software chooses to ignore the GPS data and switches into ATTI mode.

Kloo Gee Posted at 2018-2-12 21:55
In most instances I have seen where it is locked onto a sufficient number of satellites (12 in your example) and GPS goes to 0 bars is not that the GPS data is bad or its not getting a signal, but instead it is because of a Compass or Yaw error and the DJI software chooses to ignore the GPS data and switches into ATTI mode.

Unfortunately, I have no way to test that. I do believe there may be more than one issue happening at a time. I also believe the firmware has error handling issues to go along with a specific combination of hardware and sensor data handling issues. It's hard to diagnose without these events happening while debugging.

ktsummey Posted at 2018-2-12 22:32
Unfortunately, I have no way to test that. I do believe there may be more than one issue happening at a time. I also believe the firmware has error handling issues to go along with a specific combination of hardware and sensor data handling issues. It's hard to diagnose without these events happening while debugging.

There are lots of instances on these forums where users have posted their logs when having issues and it is quite clear in those instances that yaw or compass errors occur, it gives a message saying it is going to ignore the GPS data and go into ATTI mode.  

I don't claim to know all instances, but all of the instances I've investigated from these forums where GPS goes away is precipitated by other errors.  Of course there are instances where they just don't have very many satellites that they are locked onto.  That is a different issue entirely.  But when there are lots of GPS satellites locked in (i.e. 11 or more), it is something else that happens and DJI chooses to ignore the GPS data and dump to ATTI.

Kloo Gee Posted at 2018-2-12 22:46
There are lots of instances on these forums where users have posted their logs when having issues and it is quite clear in those instances that yaw or compass errors occur, it gives a message saying it is going to ignore the GPS data and go into ATTI mode.  

I don't claim to know all instances, but all of the instances I've investigated from these forums where GPS goes away is precipitated by other errors.  Of course there are instances where they just don't have very many satellites that they are locked onto.  That is a different issue entirely.  But when there are lots of GPS satellites locked in (i.e. 11 or more), it is something else that happens and DJI chooses to ignore the GPS data and dump to ATTI.

I looked into the issue a little more and I see what you're saying. Honestly, I can't remember if I was in the process of rotating the Spark. I went back and watched the flight recording and I did appear to be rotating the Spark when it lost all ephemeris data. The original flight video (minus my commentary) is here:



At the 2:06 (2:18ish on Youtube) mark I appear to be completing a rotation to make another pass at the mountain scenery when the Spark lost GPS orbital data.

It's puzzling how that is related.

GNSS related thread that I just started and you ay like to read after this one : https://forum.dji.com/thread-135156-1-1.html

ktsummey Posted at 2018-2-13 07:58
I looked into the issue a little more and I see what you're saying. Honestly, I can't remember if I was in the process of rotating the Spark. I went back and watched the flight recording and I did appear to be rotating the Spark when it lost all ephemeris data. The original flight video (minus my commentary) is here:

Flight Video

The sequence of errors in your video shows "Magnetic Filed Interference.  Exit P-GPS Mode".  This is followed by a message saying "Weak GPS signal".  I believe this is a red herring of a message because the system has purposely exited out of GPS mode due to the Magnetic Interference it has ran into and is dumping you into ATTI mode.

I think it would help to see your logs.  Can you try to upload the log for this flight to this site and then post the resulting URL here for us to look at?

http://www.phantomhelp.com/LogViewer/Upload/

My guess is that leading up to it switching away from GPS mode into ATTI mode, there are going to be a bunch of compass or yaw errors.

Kloo Gee Posted at 2018-2-12 22:46
There are lots of instances on these forums where users have posted their logs when having issues and it is quite clear in those instances that yaw or compass errors occur, it gives a message saying it is going to ignore the GPS data and go into ATTI mode.  

I don't claim to know all instances, but all of the instances I've investigated from these forums where GPS goes away is precipitated by other errors.  Of course there are instances where they just don't have very many satellites that they are locked onto.  That is a different issue entirely.  But when there are lots of GPS satellites locked in (i.e. 11 or more), it is something else that happens and DJI chooses to ignore the GPS data and dump to ATTI.

I fully agree, the most switches to ATTI I experienced were due to compass errors.
Compass errors can be caused from multiple factors, like ferro-metallic constructions, Iron ore containing soil or even an unsettled magnetic earthfield. (known as KP index in apps like UAV forecast)

This is why I have "Check Compass" in my pre-flight check list.

Kloo Gee Posted at 2018-2-13 09:48
The sequence of errors in your video shows "Magnetic Filed Interference.  Exit P-GPS Mode".  This is followed by a message saying "Weak GPS signal".  I believe this is a red herring of a message because the system has purposely exited out of GPS mode due to the Magnetic Interference it has ran into and is dumping you into ATTI mode.

I think it would help to see your logs.  Can you try to upload the log for this flight to this site and then post the resulting URL here for us to look at?

Great call. The flight record is attached. I did notice the YAW error was exactly when the Spark lost GPS orbital data.

ktsummey Posted at 2018-2-13 11:08
Great call. The flight record is attached. I did notice the YAW error was exactly when the Spark lost GPS orbital data.

Unfortunately I'm not surprised at all.  Were you able to recover your Spark?  Looking at the terrain, I'm guessing probably so since there isn't any dense vegetation.  Was there any damage?  

If the VelocityX, Y, and Z values are accurate in the logs, it looks like it was moving fast when it hit or your lost signal right at the end.

Also, it looks like you were flying from a mountain side.  In that situation, I was a bit surprised to see that you had 13 GPS satellites locked in straight away.  From the Google Earth view, it would have been reasonable that the mountain side would have blocked your view to a few satellites.  

Kloo Gee Posted at 2018-2-13 13:28
Unfortunately I'm not surprised at all.  Were you able to recover your Spark?  Looking at the terrain, I'm guessing probably so since there isn't any dense vegetation.  Was there any damage?  

If the VelocityX, Y, and Z values are accurate in the logs, it looks like it was moving fast when it hit or your lost signal right at the end.

I couldn't recover the Spark until the next day. The phone "visual" and the fact it was getting dark made it impossible to find. Not to mention unsafe, I actually fell a couple times climbing around trying to find it. When I got home I thought it through and it appeared I was looking about 100ft away from where it crashed. My wife, son, and I went back the next day and my son found it in the location we pinpointed the night before.

It was damaged. The camera was cracked, a light cover was gone, and two propellers were destroyed. When I got home I replaced the two propellers took it to the park and calibrated the sensors. It flew "normal" but I didn't want to push it. The camera even worked and the crack was obviously not in front of the lens. I was totally surprised but terrified it would fly away again hitting someone so I quickly landed it.

Going back to the incident and the flight recording I actually had the YAW error and lost GPS orbital data 2.2 seconds before the magnetic interference. I actually lost the ability to control it at the 2m 5s mark, exactly when it had the YAW error. I remember looking down at the controller because the Spark stopped responding. It then accelerated still not responding. Keep in mind this happened in 12 seconds roughly. It seemed to accelerate right after going into ATTI mode.

DJI Service in Grapevine TX has had the Spark since Feb 6th. At first, they just sent me an invoice for $347 because they claimed to find no malfunction in the flight records. Then after several phone calls, I found out they never reviewed the flight records because they said they couldn't find them. I must have synced them 5 or 6 times before I made a video of the flight record. It's funny, but DJI Support saw this on Youtube then finally escalated it. Right now they are re-evaluating the flight records to determine if it's they are going to replace it under warranty. I don't know how they can't, you can obviously see the YAW errors prior to the flyaway.

I really want the Spark / Mavic aircraft to work correctly. Right now I'm a bit terrified to fly them because of flyaway issues. I would be more than happy to help review sensor data and logics at the time of a YAW error to help determine why that's happening. Is the YAW error occurring before the orbital data loss or after.

Now I'm also curious if I can repeat it. There was another incident that happened and I thought I was reading mine. Flew the Spark without issue for a first battery, landed, and replaced the battery. Shortly after takeoff the same issue. Orbital data drop, GPS warning, compass error, then the Spark flies away. It was near exact to what I had experienced.

Waiting for support now to see if they're going to replace it. I'm sort of expecting that outcome, the Spark obviously malfunctioned.

Kloo Gee Posted at 2018-2-13 13:35
Also, it looks like you were flying from a mountain side.  In that situation, I was a bit surprised to see that you had 13 GPS satellites locked in straight away.  From the Google Earth view, it would have been reasonable that the mountain side would have blocked your view to a few satellites.

The mountain face was more than 150 meters from where I was standing.  Even in the direction of the mountain face, I had a clear view of the sky. That's why I had such a good satellite signal strength. Here are some actual pictures where I was approximately standing. To give you an idea it took my son about 20 minutes to walk to the Spark.

ktsummey Posted at 2018-2-13 14:36
The mountain face was more than 150 meters from where I was standing.  Even in the direction of the mountain face, I had a clear view of the sky. That's why I had such a good satellite signal strength. Here are some actual pictures where I was approximately standing. To give you an idea it took my son about 20 minutes to walk to the Spark.

Yeah, from Google Earth, I could tell it was some pretty treacherous terrain you were on.  I figured with a bit of persistence you would be able to find it since there isn't any trees or thick brush.  

I hope that DJI gives you a positive resolution to your case.  Sometimes companies (not just DJI) want to take the easy way out and a bit of rattling the cage helps.  

I heard back from DJI Support today. They claim there is no evidence to support a malfunction and the error messages received were after the Spark had crashed. I've filed an official complaint today as I have video and flight log evidence that the YAW, GPS, and magnetic interference error mid-flight leading to the flyaway. It's truly sad a customer has to file a complaint.

ktsummey Posted at 2018-2-14 11:56
I heard back from DJI Support today. They claim there is no evidence to support a malfunction and the error messages received were after the Spark had crashed. I've filed an official complaint today as I have video and flight log evidence that the YAW, GPS, and magnetic interference error mid-flight leading to the flyaway. It's truly sad a customer has to file a complaint.

There are almost no cases of loss of gps with dji drones I think in the last two years I’ve seen 3 cases, I’ve seen plenty where aircraft is flown under cover ie trees bridges which directly block out signal.
Most if not all cases are due to problems with compass and many of these are due to taking off from unsuitable ground or flying in areas of magnetic interference or adding something to aircraft that may have effect of causing problem for compass.

Why would a compass error disable GPS?
Orientation (compass data) and position (GPS data) are different but related.
When the Spark is moving and getting position information from the GPS that tells the Spark that it is travelling in a different direction from what it's getting from compass data, The Spark programming can't work with the data conflict.
The solution is to drop data from one source and since the Spark can't fly without a compass but can without GPS, it's the GPS data that gets dropped.

Is the YAW error what the Spark programming produces when the compass and GPS report the Spark flying in different directions?

ktsummey Posted at 2018-2-14 13:51
Is the YAW error what the Spark programming produces when the compass and GPS report the Spark flying in different directions?

Yaw error is a symptom of compass problem, the aircraft is starting to go in a different direction than controller is commanding, it is usually followed closely by IMU counter heading problem where IMU is trying to compensate for incorrect heading giving by controller, we then usually see aircraft drop gps and go to Atti mode, although you say Aircraft was not responding to your commands, if you are using phantomhelp log you can check in the CSV file your stick movements also pitch yaw and roll of the aircraft to see if it was responding.
In Atti mode to see if aircraft is responding you must make clear and full 100% stick movements anything short of this will result in aircraft flying away on the wind.

hallmark007 Posted at 2018-2-14 14:58
Yaw error is a symptom of compass problem, the aircraft is starting to go in a different direction than controller is commanding, it is usually followed closely by IMU counter heading problem where IMU is trying to compensate for incorrect heading giving by controller, we then usually see aircraft drop gps and go to Atti mode, although you say Aircraft was not responding to your commands, if you are using phantomhelp log you can check in the CSV file your stick movements also pitch yaw and roll of the aircraft to see if it was responding.
In Atti mode to see if aircraft is responding you must make clear and full 100% stick movements anything short of this will result in aircraft flying away on the wind.

Thanks for all your input. You seem to have better insight than most into the YAW error. I appreciate you.

I fail to see how DJI, or anyone else, can fault the pilot if the Spark / Mavic suddenly has compass errors mid-flight after passing pre-flight checks especially if the Spark / Mavic was already flown safely with no issues in the exact flight path. I do pre-flight checks before every launch which include checking the sensors (IMU/compass), and GPS satellite and signal strength.

What I have experienced and read dozens of similar cases online is the root cause of Spark / Mavic flyaways starts with an unexpected YAW (compass?) error mid-flight. Then, if the Spark is lost or it crashes, DJI tries everything to make it sound like a pilot error, and it may be at that point. However, it's the unexpected compass / YAW error that initially caused the incident forcing a pilot to attempt to recover control of the drone.

I filed a complaint with my state attorney general, but expect nothing can probably be done. In my interaction with DJI Support, they actually said all the errors had occurred after the crash which is complete garbage. There is both video and log evidence that shows the YAW error and magnetic interference occurred in-flight, it flew at a high rate of speed a solid 10s after those two errors occurred.

As one of Bestbuy's elite members, I'll also be discussing this matter with them as well. At some point, one of DJI's UAV is going to cause injury due to a flyaway and lawyers for the injured will name Bestbuy since there is little that can be done with a Chinese based company.

ktsummey Posted at 2018-2-16 08:52
Thanks for all your input. You seem to have better insight than most into the YAW error. I appreciate you.

I fail to see how DJI, or anyone else, can fault the pilot if the Spark / Mavic suddenly has compass errors mid-flight after passing pre-flight checks especially if the Spark / Mavic was already flown safely with no issues in the exact flight path. I do pre-flight checks before every launch which include checking the sensors (IMU/compass), and GPS satellite and signal strength.

Not to sure if appealing dji’s decision will help, but I think this should be your first option, I have seen similar being offered warranty , I’m not sure what their reason for refusing warranty is, you probably have already been told.
The yaw error IMU heading compass loss of gps, although a symptom of all dji drones with compass problems. But spark for some reason has or had a much higher % of this problem 10 fold more than any other drone, it was very prevalent here and many cases all throughout January, but all of a sudden we see very few cases so whether this has been fixed through firmware update I don’t know and I’m sure if it was dji won’t admit to it, but there are certainly a lot less cases of this been reported on this forum of late.
Maybe try to contact a moderator here and ask them to get dji engineers to take another look at your logs , it may not help but you can only try.
I wish you luck my friend.

@ktsummey, I wish you luck with your appeal to DJI. It certainly sounds like you have a very reasonable case for DJI to replace it under warranty.

I suffered a Spark flyaway in December, in what sounds similar to what you've reported here (e.g. compass error, drone accelerated at high speed on its own, controller was unresponsive, etc.), except I wasn't able to recover my drone because it crashed into the sea. Like you, I did everything by the book during pre-flight checks and take-off. Luckily I was very fortunate to receive a replacement Spark in January, but now every time I fly it - no matter the location - I get compass errors and am paranoid about another flyaway and/or injuring someone (particularly because when mine flew away the logs said it hit as much as 70km/h in speed!).  I'm absolutely convinced that the current firmware version is flawed.

I just don't trust this drone anymore and am seriously thinking about selling it.

hallmark007 Posted at 2018-2-14 13:22
There are almost no cases of loss of gps with dji drones I think in the last two years I’ve seen 3 cases, I’ve seen plenty where aircraft is flown under cover ie trees bridges which directly block out signal.
Most if not all cases are due to problems with compass and many of these are due to taking off from unsuitable ground or flying in areas of magnetic interference or adding something to aircraft that may have effect of causing problem for compass.

Thanks so much for providing such clear explanations on this thread, the issue makes a lot more sense now.

warrenski Posted at 2018-2-16 12:31
Thanks so much for providing such clear explanations on this thread, the issue makes a lot more sense now.

Your very welcome..

I think it's about the data that was downloaded from the satellites got suddenly incorrect and did a little glitch  confusion to the spark

DJI SUCKS !!!!!

DJI SUCKS !!!!!

wsshay3@gmail.c Posted at 2018-2-16 13:51
DJI SUCKS !!!!!

To be fair, while DJI's consumer-segment products aren't perfect (whose are?), they're really exceptional pieces of tech if you stop for a minute to consider just how advanced these aircraft are! I for one applaud DJI's innovations and will happily keep supporting their brand, while hoping that with the help of the community they'll do more to correct the issues that are reported here.

Here is a new website: UAVFlyaways.com

This website will be keeping track of flyaways and current issues with UAVs. It's constantly being updated and will soon include an email for pilots to share their experiences piloting UAVs. While I agree DJI has developed some solid technology, they have some solid issues that will eventually result in injury or damage. UAV insurance is popping up more frequently, and lawyers are advertising for "drone" personal injury cases. Pilots, not DJI, are going to be held responsible for the results of a flyaway incident. Some states have laws protecting pilots who use a reasonable approach to operating a UAV. However, for a pilot to operate a UAV that has a known history of flyways makes a pilot harder to defend. Laws will differ state by state (in the US) and in some states has a statute of limitations of 2 years, meaning a pilot can be sued for an incident occurring up to two years after an incident. My suggestion is to keep an accurate log of all incidents involving your UAV and look into private UAV liability insurance with a coverage starting at $100k USD.

^  

Now it makes sense. Again more issues since the latest fw update and GO4 update.

Flyaways can be a problem, but from what I understand they should not be landing on people or flying into buildings. They lose connection and auto land where they are unless the pilot totally wiped out batts. Other flights I have seen reported were more often pilot error. Returning upwind, stuff like that.  Of late, it's connection and GPS and compass errors. For me it only happens with the Spark. Other items non DJI with GPS fly just fine.

Now it makes sense. Again more issues since the latest fw update and GO4 update.

Flyaways can be a problem, but from what I understand they should not be landing on people or flying into buildings. They lose connection and auto land where they are unless the pilot totally wiped out batts. Other flights I have seen reported were more often pilot error. Returning upwind, stuff like that.  Of late, it's connection and GPS and compass errors. For me it only happens with the Spark. Other items non DJI with GPS fly just fine.

My Spark is sort of grounded until this gets remedied. Others are selling theirs and buying Mavic or Mavic Air. One put it interestingly enough on FB.... seems coincidental that these Spark birds get updated and are not so much the happening item right after the new Mavic Air release.

miketmtpro Posted at 2018-2-19 17:01
^  

Now it makes sense. Again more issues since the latest fw update and GO4 update.

If that were true my Spark would not have flown head-on into the side of a mountain at 14 m/s. There was absolutely no rc response from the time of the YAW error until the crash.

miketmtpro Posted at 2018-2-19 17:01
^  

Now it makes sense. Again more issues since the latest fw update and GO4 update.

I wish that were true. Best case scenario is you can control it in atti mode, however, in dozens of cases it was not responding to the RC.

ktsummey Posted at 2018-2-19 18:33
I wish that were true. Best case scenario is you can control it in atti mode, however, in dozens of cases it was not responding to the RC.

Yes that happens often of late since latest FW and GO App updates.

Don't fly far or get too crazy. I flew VLOS from my back yard not even 600' out and had error after error reported. GPS would come and go, ATTI kicked in several times and then I just landed it. Have not flown since. They need to fix these problems.

Biggest issue is the "disconnect" then you feel like damn I have no control...give it a sec, push back toward you, use the ALT Indicator mode instead of Map and you should be able to get it back. Establishing N and basic headings yourself is key for any RC drone flying.. GPS or not. If the drone is too far out of visual range, don't freak out. Do the basics and you can get it back. If RC never returns then it's probably going to be a fly away.

I have seen half a dozen people with RC's lose them when they get out of range. Toy quads to nicer ones. Spark doesn't have dual IMU and Compass from what I heard, so any software issue will cause it to default to ATTI.

Still, I'm with many others on this problem. It was fine before the last update. It's not even Android or iOS specific.

miketmtpro Posted at 2018-2-19 17:01
^  

Now it makes sense. Again more issues since the latest fw update and GO4 update.

The Spark is designed to switch to ATTI mode when GPS is weak. Intelligent flight modes (vision,obstacle avoidance,etc) are not available in ATTI mode. In my instance I could not get the Spark to respond two seconds before it went in ATTI mode, the Spark accelerated and crashed.

ktsummey Posted at 2018-2-19 21:59
The Spark is designed to switch to ATTI mode when GPS is weak. Intelligent flight modes (vision,obstacle avoidance,etc) are not available in ATTI mode. In my instance I could not get the Spark to respond two seconds before it went in ATTI mode, the Spark accelerated and crashed.

Seems more common of an issue these days

miketmtpro Posted at 2018-2-19 22:01
Seems more common of an issue these days

I think it's been an issue, however, it's not being reported. The Spark advertising has targeted a market of users on the premise that the Spark is an entry-level drone. The sell the phone control, gesture controls, etc and it looks really cool. Therefore customers purchase these that are new to UAVs and when there is a crash they just don't say anything. I'll say the majority of the crashes are a pilot error because these are new inexperienced operators however there are a significant number of flyaways that are not being reported because the operators are not experienced/trained to understand what has just happened. I suspect as popularity arises, so will awareness, and reports will continue to increase.

I think all crashes or loss of RC model results in blame being tossed around so the fault is away from the pilot.  As drones that can be flown 600 meters from the pilot, fall in price, the incidence of crashes/loss will increase.  Flying far from the pilot is risky.  And, pilots leave out little things to the story like that they were flying behind obstacles, around buildings, or along a river under bridges.

Gunship9 Posted at 2018-2-20 09:48
I think all crashes or loss of RC model results in blame being tossed around so the fault is away from the pilot.  As drones that can be flown 600 meters from the pilot, fall in price, the incidence of crashes/loss will increase.  Flying far from the pilot is risky.  And, pilots leave out little things to the story like that they were flying behind obstacles, around buildings, or along a river under bridges.

I don't disagree that there are a lot of pilot errors, however, there are issues with the Spark. I finally received my unrepaired Spark back from the DJI Service center in Grapevine, TX. I uploaded every flight record and found in a location, I've been to more than 5 times, one flight record showed the Spark having the same episode as the day it crashed, minus the crash. It started with an error "GPS Position NoMatch" then "Yaw Errors", followed by "Magnetic Interference". It was flying over water, free of any structures, nothing remotely close where it had been flown many times before. There is a difference between the two episodes, the day it crashed you could hear the "acceleration" whereas the day it didn't crash there was no acceleration. It's not a permanent malfunction (like a Spark reboot to restore normal ops), it only lasts a matter of seconds (10 to 45 seconds), and it happens mid-flight after sensors are reporting IMU and Compass are in "good" states. I'm not sure how there is a magnetic interference unless the aircraft is interfering with itself lacking proper shielding somewhere in the design. I also don't understand how DJI can respond asking you to operate the Spark in a location free of magnetic interference when there is no indication the location is NOT a safe place to launch the Spark.

Another curious event. After I received my Spark back, I'm not sure what the DJI Service center did, but the forward two lights weren't working. I had to reflash the Spark, then restore it to factory settings to get it to work. I told the DJI Service center that I tested it before I sent it in and everything worked normally. I was missing a light diffuser and had to change some props, but it operated as expected. When I got it back it wasn't in a flyable state, so I tend to wonder if DJI is just trying to get its customers to purchase another Spark as a way to move old Spark product out in the wake of the Mavic Air release.

I believe there are lots of pilot (hidden) errors DJI has to deal with. However, DJI is hiding issues of their own pointing the finger at pilot error. The Spark is marketed as a beginner, entry-level UAV, that can be operated from a phone. There are ZERO indications to customers the Spark can malfunction mid-flight and the "beginner" pilot is expected to understand how to react to ATTI mode.