Shocking fly-away event today, after 2 years of stable and successful flights with Inspire 2.  Location was near the edge of a No Fly Zone, with full authorization. Job involved flying at 60 ft near some boats at a pier in downtown boston harbor.  Flew first part of job - all good, no problems.  Landed to change batteries.  Aircraft then says - Calibrate My Compass.OK - did the circle dance - Calibration approved.  Take off to do part 2 of this little job.  All seems OK, aircraft at about 20 ft up.  Then suddenly, it flys away on its own, gaining altitude and flying in a circle with radius of about 300 ft.  No control possible.  RTH not responding.  After flying in this circle for about 20 seconds, the aircraft crashes into the side of a building and falls to the ground.  Totally destroyed.  All firmware was updated 8 weeks ago, and many good flights since then.  Any clues?  Could it be caused by boats nearby with their radar and radios?  Compass calibration seemed OK, but maybe was no good..? Insurance will probably cover most of the loss, but it is still traumatic. Please help me understand what happened.

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I think you should not calibrate compass near metal or near compass error location.

Hi, good day steve. We're sorry to know about the incident happened to your DJI Inspire 2. The best way that we can advise you right now is to contact our support team to start up a ticket: https://www.dji.com/support. We have the professional team who would do their best to find out the reason for the incident and then the corresponding resolution would be provided. Please note that DJI will not perform data analysis for cases occurring after the expiry of the warranty period; otherwise, valid charges will apply. Thank you for your kind and understanding. Have a good one.

DJI Gamora Posted at 5-1 09:58
Hi, good day steve. We're sorry to know about the incident happened to your DJI Inspire 2. The best way that we can advise you right now is to contact our support team to start up a ticket: https://www.dji.com/support. We have the professional team who would do their best to find out the reason for the incident and then the corresponding resolution would be provided. Please note that DJI will not perform data analysis for cases occurring after the expiry of the warranty period; otherwise, valid charges will apply. Thank you for your kind and understanding. Have a good one.

Hi, Gamora -
I will start a support ticket.  What are the "valid charges?"

FVP Posted at 5-1 09:22
I think you should not calibrate compass near metal or near compass error location.

thanks, FVP -
The Compass Calibration was completed, and Go App said it was OK to fly.  So why would the aircraft take off on its own like a horse out of the barn??   Puzzled.

steve＼@stevedunwell.com Posted at 5-1 11:27
thanks, FVP -
The Compass Calibration was completed, and Go App said it was OK to fly.  So why would the aircraft take off on its own like a horse out of the barn??   Puzzled.

I'm sorry to hear bad news ... Usually the system is demanding compass calibration when some magnetic interference is sensed in proximity, i.e. iron deposits, big steel structures etc. Performing calibration in this scenario is a suicidal decision, because it will align to new, magnetically "spoiled" environment. I would abort the mission immediately after receiving such message and move to a different location to check compass readings and investigate the issue, but never do a ritual dance at the spot. Unfortunately manual doesn't explain clearly how to react to system demand in this situation, I believe.

steve＼@stevedunwell.com Posted at 5-1 11:24
Hi, Gamora -
I will start a support ticket.  What are the "valid charges?"

Thank you for the additional information. The valid charges will depend on the damage assessment that our professional team will conduct on your drone. Thank you and have a good one.

Matthew Dobrski Posted at 5-1 12:10
I'm sorry to hear bad news ... Usually the system is demanding compass calibration when some magnetic interference is sensed in proximity, i.e. iron deposits, big iron structures etc. Performing calibration in this scenario is a suicidal decision, because it will align to new, magnetically "spoiled" environment. I would abort the mission immediately after receiving such message and move to a different location to check compass readings and investigate the issue, but never do a ritual dance at the spot. Unfortunately manual doesn't explain clearly how to react to system demand in this situation, I believe.

Thanks, Matthew -
I understand your point about the compass calibration.  Can you explain why this would lead to a Fly Away and disconnect?

steve＼@stevedunwell.com Posted at 5-1 12:40
Thanks, Matthew -
I understand your point about the compass calibration.  Can you explain why this would lead to a Fly Away and disconnect?

Steve, it is hard to speculate what exactly happen without flight log analysis. Apparently the navigation system get confused with conflicting data from GPS, true magnetic North and new "assumed" North. But that's my best guess only ...

steve＼@stevedunwell.com Posted at 5-1 12:40
Thanks, Matthew -
I understand your point about the compass calibration.  Can you explain why this would lead to a Fly Away and disconnect?

Complex algorithms control the output of the flight controller and unfortunately there isn't as much fail safe in these systems as there are in more professional UAS.

Did you try switching to atti mode when you lost control? Not that it would help much imo but it's unfortunate DJI has no reversion modes for circumstances just like this.

HyperSpectral Posted at 5-2 04:49
Complex algorithms control the output of the flight controller and unfortunately there isn't as much fail safe in these systems as there are in more professional UAS.

Did you try switching to atti mode when you lost control? Not that it would help much imo but it's unfortunate DJI has no reversion modes for circumstances just like this.

Hello, HyperSpectral - No, I did not switch to ATTI mode.  Aircraft took off so quickly, then out of VLOS.  Data record shows it accelerating continuously until impact at 60 km/hr....all in 20 secs....flight track was circular, with take-off point on the rim of the circle. ...BTW - after 2 yrs of flying this, I am still not comfortable with ATTI...especially in an emergency.

steve＼@stevedunwell.com Posted at 5-2 05:26
Hello, HyperSpectral - No, I did not switch to ATTI mode.  Aircraft took off so quickly, then out of VLOS.  Data record shows it accelerating continuously until impact at 60 km/hr....all in 20 secs....flight track was circular, with take-off point on the rim of the circle. ...BTW - after 2 yrs of flying this, I am still not comfortable with ATTI...especially in an emergency.

The idea behind reversion modes isn't necessarily so you can regain complete control (although it gets as close as possible), it's so you can mitigate risk as much as possible with the controls available.

I suggest you practice in atti mode, or with a cheaper system, so you're proficient in operating one of these systems without stabilization.

DJI should fix your inspire 2 for free if what you say is what happened. Have you uploaded the flight log to airdata?

HyperSpectral Posted at 5-2 04:49
Complex algorithms control the output of the flight controller and unfortunately there isn't as much fail safe in these systems as there are in more professional UAS.

Did you try switching to atti mode when you lost control? Not that it would help much imo but it's unfortunate DJI has no reversion modes for circumstances just like this.

Compass calibration of DJI systems was discussed to death here and on any other related forum. It was concluded that this procedure should be carried as seldom as possible, perhaps after every FW update or after moving to another part of the world hundreds miles away. It's also obvious that compass calibration must be done in magnetic interference free environment. Sudden warnings displayed by Go 4 app are indications that something is magnetically wrong in particular place. Unfortunately the app suggests compass calibration, which is plain stupid. Proper action is to abort the mission ASAP, move to a different location and check compass reading there.  

HyperSpectral Posted at 5-2 09:03
The idea behind reversion modes isn't necessarily so you can regain complete control (although it gets as close as possible), it's so you can mitigate risk as much as possible with the controls available.

I suggest you practice in atti mode, or with a cheaper system, so you're proficient in operating one of these systems without stabilization.

Aircraft is out of warranty, so I don't expect much from DJI. (or am I missing something?)  Nonetheless, I will start a repair ticket with them, at least so that they know this aircraft went rogue at great risk. ...I have the CSV and DAT files and I will upload to AirData.  Your point about ATTI is helpful. Thank you.

steve＼@stevedunwell.com Posted at 5-2 10:12
Aircraft is out of warranty, so I don't expect much from DJI. (or am I missing something?)  Nonetheless, I will start a repair ticket with them, at least so that they know this aircraft went rogue at great risk. ...I have the CSV and DAT files and I will upload to AirData.  Your point about ATTI is helpful. Thank you.

Ah sorry I misunderstood. Unlikely to be warrantied then although they will likely offer a discounted repair price.

Thanks for offering to upload the data, it will certainly add to my curiosity
One last thought, memorize the emergency motor stop function for whichever system you're operating, it's called CSC for DJI afaik

Matthew Dobrski Posted at 5-2 10:07
Compass calibration of DJI systems was discussed to death here and on any other related forum. It was concluded that this procedure should be carried as seldom as possible, perhaps after every FW update or after moving to another part of the world hundreds miles away. It also obvious that compass calibration must be done in magnetic interference free environment. Sudden warnings displayed by Go 4 app are indications that something is magnetically wrong in particular place. Unfortunately the app absurdly suggest compass calibration, which is plain stupid. Proper action is to abort the mission ASAP, move to a different location and check compass reading there.

I came to that same conclusion just based on countless hours working with DJI's flight controllers, it's nice to hear it's been confirmed through other testimonials.

I seldom calibrate the imu or compass anymore unless I see abnormally high bias even in a sparse area.

Matthew Dobrski Posted at 5-1 12:10
I'm sorry to hear bad news ... Usually the system is demanding compass calibration when some magnetic interference is sensed in proximity, i.e. iron deposits, big iron structures etc. Performing calibration in this scenario is a suicidal decision, because it will align to new, magnetically "spoiled" environment. I would abort the mission immediately after receiving such message and move to a different location to check compass readings and investigate the issue, but never do a ritual dance at the spot. Unfortunately manual doesn't explain clearly how to react to system demand in this situation, I believe.

Hi Sorry to hear about your flight/crash/event.  I was wondering if this very issue was what happened when I heard about this from D.A. who was with you at the time of the event.  (Friend of the family) I'm guessing he told you about his experience with me last September.  The compass calibration advice given by Matthew Dobrski is spot on in my opinion. I've had similar events with my old I1 and learned to notice the symptoms right at take off.  I haven't had the flying issue with either of my I2's but I do frequently run into compass warnings and take the precautions mentioned above. I was wondering if you were flying from a concrete platform with lots of re-bar steel, parking structures are terrible, thick slabs of concrete, between the Ferries, reinforced water way, microwave transmissions, I'm guessing reinforced walk way, odds aren't in your favor.  I don't know if switching between "P" and "ATTI" mode would have helped or not.  Worth a try??  For sure a reason to practice ATTI mode all the time and make sure you've got a "Kill" option (stick movement that shuts off the motor mid flight) as part of your pre-flight. If that doesn't make sense message me and I'll explain deeper.  Once again, sorry to hear about your event. It sounds like your only down an aircraft and a more than frustrating experience. It feels embarrassing and humbling but hey,  no injuries, no property damage is a bonus.  Thanks for sharing, it keeps us all a bit sharper.

After a couple years of flying experience we tend to get a bit comfortable.  Staying ontop of these forums and hearing other's stories and experiences are lessons learned, hopefully in advance.

Learning to "FLY" our aircraft is extremely important...in ATTI Mode.  Practicing Lost Orientation....flying in atti mode and getting yourself disoriented.....you have to be able IN ADVANCE to know what to do in an emergency.  Practice every week what you'll do in an emergency.  Really I am truly sorry your AC crashed!!  Sounds horrible.

Saying it "was only 20 seconds"  well with more practice, and having emergency procedures practiced and part of your "tool box"....... 1- you already had a calibration issue    2- that issue should have had you thinking about " what CAN go wrong" and if something does SWITCH TO ATTI MODE......the bird should hover with the air flow until you fly it home.

Again I am truly sorry, and just wanted to give others some things to think about.........remember, don't get too comfortable, bad things happen!

Randy
Aerial Traffic
https://www.facebook.com/aerial.traffica

Loose control of the drone? ATTI, ATTI, ATTI, AAAATTTTIIII! ;)

That should be the first you think about in a situation like that.

Hello, im posting my problem here because the forum wont let me post anywhere else.

My Mavic Air was flying across a river in Tripod mode, it was approximately 30m away from me when it all of a sudden jumped out of tripod mode and at max speed flew uncontrollably into a tree...(i rescued the drone by traversing the river)

I did not attempt to fly over water again. Instead, on dry land i flew straight up. Which worked no problem. So i flew across a valley (great scenery) and then the controller beeped at me. I hadn't heard this beep before, it was not the low battery warning beep of the drone (but controller did have a low battery). I was nervous about losing the drone again if the controller lost battery, so i pressed return home.

It came home before the controller lost battery. But would it still have returned home if it did?

I then took drone home, changed propellors and updated software

My next flight attempt was again. Just going to go directly above my head (to test)

I was out front of the Fortress in Split Croatia (where Drones are allowed)

However it gave me a warning about the flight zone and asked me to accept responaibility. Which i did.

The props where spinning and RPM increased to take off but drone didnt move...

Then i couldnt stop it at all. Get a message saying props at max speed (but drone not moving)

So i pick it up and remove the battery

My drone has a mind of its own now... Not sure what to do

Matthew Dobrski Posted at 5-1 12:10
I'm sorry to hear bad news ... Usually the system is demanding compass calibration when some magnetic interference is sensed in proximity, i.e. iron deposits, big iron structures etc. Performing calibration in this scenario is a suicidal decision, because it will align to new, magnetically "spoiled" environment. I would abort the mission immediately after receiving such message and move to a different location to check compass readings and investigate the issue, but never do a ritual dance at the spot. Unfortunately manual doesn't explain clearly how to react to system demand in this situation, I believe.

@Matthew Very interesting observation

Matthew Dobrski Posted at 5-1 12:10
I'm sorry to hear bad news ... Usually the system is demanding compass calibration when some magnetic interference is sensed in proximity, i.e. iron deposits, big iron structures etc. Performing calibration in this scenario is a suicidal decision, because it will align to new, magnetically "spoiled" environment. I would abort the mission immediately after receiving such message and move to a different location to check compass readings and investigate the issue, but never do a ritual dance at the spot. Unfortunately manual doesn't explain clearly how to react to system demand in this situation, I believe.

@Matthew Very interesting observation

I would like to see DJI post the results of the data reads to see what happen in the events
it would be a good learning experience  for all

This is a really good description of what can go wrong when you calibrate the compass in a scenario where you shouldn't. The compass is not bulletproof and you shouldn't rely on the app alone to tell you what to do. If the app suddenly gives you a compass error on the ground, you need to figure out why. Move the drone around while watching the compass bar to see if it changes. More likely than not you have put it near something magnetic.

That the drone started doing circles in an uncontrolled fashion is indicative of bad compass data that is making it impossible for the drone to fly using GPS positioning. The circular motion is called TBE (Toilet Bowl Effect) and was far more common in the early days of DJI Phantoms as it was even more vulnerable then. As mentioned above, if you see anything like this, you immediately switch to ATTI.

I highly suggest everyone read, understand and practice what is written here: Compass Calibration Primer PDF

ianwood Posted at 5-7 22:02
This is a really good description of what can go wrong when you calibrate the compass in a scenario where you shouldn't. The compass is not bulletproof and you shouldn't rely on the app alone to tell you what to do. If the app suddenly gives you a compass error on the ground, you need to figure out why. Move the drone around while watching the compass bar to see if it changes. More likely than not you have put it near something magnetic.

That the drone started doing circles in an uncontrolled fashion is indicative of bad compass data that is making it impossible for the drone to fly using GPS positioning. The circular motion is called TBE (Toilet Bowl Effect) and was far more common in the early days of DJI Phantoms as it was even more vulnerable then. As mentioned above, if you see anything like this, you immediately switch to ATTI.

Fully agree!

Matthew Dobrski Posted at 5-1 12:10
I'm sorry to hear bad news ... Usually the system is demanding compass calibration when some magnetic interference is sensed in proximity, i.e. iron deposits, big steel structures etc. Performing calibration in this scenario is a suicidal decision, because it will align to new, magnetically "spoiled" environment. I would abort the mission immediately after receiving such message and move to a different location to check compass readings and investigate the issue, but never do a ritual dance at the spot. Unfortunately manual doesn't explain clearly how to react to system demand in this situation, I believe.

"I would abort the mission immediately after receiving such message and move to a different location to check compass readings and investigate the issue, but never do a ritual dance at the spot. Unfortunately manual doesn't explain clearly how to react to system demand in this situation, I believe"

Steve, Matthew's Absolutely on point. IN/NEAR Vessels (You were at a Marina) I've had a LOT of issues. 1 is Marine Radios and the other is MARINE RADARS. They emit Massive Amounts of Interference...Magnetic Signals.
Most Mariners wouldn't fire up their Radar IN a Marina (usually plays hell with most TV Reception, INCLUDING Cable Reception so the rest of the Marina's Boat Residents wouldn't be real happy either), However it (the Magnetic interference from Activated RADARS) will absolutely WIG OUT Your IMU's, & block ALL Communication Capabilities between RC & Aircraft...after it's out of Your hands, only the data logs can reveal WHY the drone did what it did?
You might want to consider the possibility that someone IN THE MARINA, did this INTENTIONALLY, because they already knew of the magnetic transmissions FROM their Radar Unit would destroy Your communication interface?
There are a LOT of People who don't like drones flying around, regardless of the fact that You're a professional, had valid permission(s), and were on a JOB trying to make a living.
Just 2 cents fm a pilot who's done a lot of marina, waterfront (& anchorage) footage for years?
Sorry for Your loss, it sux to crash, it sux worse when left helpless to do nothing but watch the crash.

I fly A LOT around HUGE vessels (think LNG tankers), either at sea or from land around these guys. I’ve quite a few compass errors in flight or before take off and it usually goes away. I’ve never lost a bord, have had to calibrate compass maybe once because it was really stubborn. Only once did I have the drone going really weird (yawing left/right, cam wobbling left/right) and thought oh boy there she goes, but now, I switched to ATTITUDE, flew away from the ship (open sea, with the ship going 19kts) and resumed my flight around it. Our ships have a side radar operating on the X band for wave detection and hull structural integrity monitoring). I believe that it’s the culprit, the other on board equipment don’t seem to affect them. It’s just that a 300-meter, 180.000-ton ship will cause magnetic disturbances. I have flown quite a bit around big harbors, and your case still is strange. I hope you can get it fixed though.

Hi Steve.  Wondering how you made out on the I2 crash.  Did you find out what caused the problem?

Is there anyway to upload a flight log?

I am sorry for this fellows loss, but I am happy I read about this as I have not ever heard of TBE. I appreciate the education on this and I will practice more in ATTI mode.

I am not new to UAS's but am getting a new I2  in a couple days (I fly an I1P, P4P and old school MP) and doing some reading on the aircraft.

Thank you to the veterans here for the tips and stories.