Flyaways are real...

[Deleted member 29014]

After 4 years of flying DJI drones and scoffing at flyaway reports, it is with much shame I admit the do happen. A week ago I was working a construction project with a brand new P4P. I launched the aircraft manually in GPS mode to a planned 100 feet altitude, The A/C passed 100, tried to reduce throttle, continued to well over 200 feet, began to fly north, stick commands (direction & throttle) were inoperative, activated RTH, A/C returned to overhead launch site but would not descend, turned controller off for 5 seconds, turned back on , not change, went to manual mode (atti) A/C drifted north still climbing, lost sight, came down and crashed.

Flight record shows multiple ESC errors. My dealer shipped it back to DJI, awaiting DJI's decree, what do you think are my chances I 'll get a new one?

 

[LarBear360]

After 4 years of flying DJI drones and scoffing at flyaway reports, it is with much shame I admit the do happen. A week ago I was working a construction project with a brand new P4P. I launched the aircraft manually in GPS mode to a planned 100 feet altitude, The A/C passed 100, tried to reduce throttle, continued to well over 200 feet, began to fly north, stick commands (direction & throttle) were inoperative, activated RTH, A/C returned to overhead launch site but would not descend, turned controller off for 5 seconds, turned back on , not change, went to manual mode (atti) A/C drifted north still climbing, lost sight, came down and crashed.

Flight record shows multiple ESC errors. My dealer shipped it back to DJI, awaiting DJI's decree, what do you think are my chances I 'll get a new one?

The good news is you recovered the AC and able to send it back to DJI. They will analyze the .dat file and make a determination. The .dat file will either support or contradict your description. If everything happened as you described, I would say they owe you a new machine. I've heard similar stories where DJI did the right thing and replaced the drone.

 

[Meta4]

Flight record shows multiple ESC errors. My dealer shipped it back to DJI, awaiting DJI's decree, what do you think are my chances I 'll get a new one?

Here's what your flight data looks like:
DJI Flight Log Viewer - PhantomHelp.com
It's pretty cleasr that something's not right with that flight lig.
There are no ESC errors showing in the data but it clearly shows the Phantom ascending when you had the left stick pulled down.
It also says RTH: Preascending at 1:56 when the drone was at 188 ft even though the RTH height is set at 66 ft.

 

[sar104]

After 4 years of flying DJI drones and scoffing at flyaway reports, it is with much shame I admit the do happen. A week ago I was working a construction project with a brand new P4P. I launched the aircraft manually in GPS mode to a planned 100 feet altitude, The A/C passed 100, tried to reduce throttle, continued to well over 200 feet, began to fly north, stick commands (direction & throttle) were inoperative, activated RTH, A/C returned to overhead launch site but would not descend, turned controller off for 5 seconds, turned back on , not change, went to manual mode (atti) A/C drifted north still climbing, lost sight, came down and crashed.

Flight record shows multiple ESC errors. My dealer shipped it back to DJI, awaiting DJI's decree, what do you think are my chances I 'll get a new one?

The cause of some of the behavior is clear, but not all. The uncommanded ascent and lack of altitude control is obvious but the reason is not. It may have been related to the vision system, which did not register any increase in height after takeoff. I've not seen that before and I don't know what effect it would have. Did you have any other equipment on the aircraft, or perhaps forgot to remove the vision sensor protective films?

The horizontal behavior of the aircraft is normal. It appears that you mis-remembered when you switched to ATTI mode - that was at 60 seconds and before you activated RTH. It was in ATTI for 21 seconds and it did drift 100 m NE during that period. At 81 seconds you initiated RTH and it returned to the home point as expected, but did fail to descend. However, the subsequent movement to the NW and then SE occurred because at 162 seconds you applied full left aileron for 1.2 seconds and then full right aileron for 6.5 seconds.

The end of the flight is not apparent because no descent is recorded - presumably the downlink was lost.

 

[Deleted member 29014]

Here's what your flight data looks like:
DJI Flight Log Viewer - PhantomHelp.com
It's pretty cleasr that something's not right with that flight lig.
There are no ESC errors showing in the data but it clearly shows the Phantom ascending when you had the left stick pulled down.
It also says RTH: Preascending at 1:56 when the drone was at 188 ft even though the RTH height is set at 66 ft.

When I plug the flight record in Healthydrones I get a ton of ESC errors.

 

[Deleted member 29014]

The cause of some of the behavior is clear, but not all. The uncommanded ascent and lack of altitude control is obvious but the reason is not. It may have been related to the vision system, which did not register any increase in height after takeoff. I've not seen that before and I don't know what effect it would have. Did you have any other equipment on the aircraft, or perhaps forgot to remove the vision sensor protective films?

The horizontal behavior of the aircraft is normal. It appears that you mis-remembered when you switched to ATTI mode - that was at 60 seconds and before you activated RTH. It was in ATTI for 21 seconds and it did drift 100 m NE during that period. At 81 seconds you initiated RTH and it returned to the home point as expected, but did fail to descend. However, the subsequent movement to the NW and then SE occurred because at 162 seconds you applied full left aileron for 1.2 seconds and then full right aileron for 6.5 seconds.

The end of the flight is not apparent because no descent is recorded - presumably the downlink was lost.

View attachment 104243

SAR104 what app or software did u use to get this graphic?

 

[sar104]

SAR104 what app or software did u use to get this graphic?

Wavemetrics Igor Pro.

 

[Fly Dawg]

When I plug the flight record in Healthydrones I get a ton of ESC errors.

The ESC Errors are shown below. ( You will only see the time they were there in total, as Airdata may say repeated X number of times) In fact immediately after you released the throttle at ~26.9 Seconds, the throttle never responded to your inputs again afterwards. On a note, this is the 3rd one of these types of events I have seen with a P4. Primarily involving a non-responsive throttle. Although the other inputs could be affected as well. To me this is an issue with the RC of some sort. Hopefully you return your RC with the AC.

 

[Deleted member 29014]

So I'm getting screwed by DJI( not surprised):
For your case CAS-2313770-X8X3K6, we have finished the analysis, and the result is as follows:

The aircraft was in P-GPS mode and was responsive to pilot command. P mode : P-mode works best when GPS signal is strong. The aircraft utilizes GPS and the vison system to locate itself, stabilize, and navigate between obstacles.

At t=02:55s, relative height=63m, flight log cuts off. Pilot commanded roll right while unit is landing. Aircraft flight log cut off, pilot turns off app.

According to the analysis, the incident was not caused by any product malfunction factors. As such, we could not provide warranty service.We can still proceed with the repairs however, you need to cover the repair fees.

We will have our quotation team to follow up on your case soon.

Your understanding and cooperation will be highly
appreciated.

Once again, sorry for any inconvenience, and thanks for
your support.

My response:

Your facts are incorrect. I have been flying DJI products for 4 years and am well aware of their operation. The drone was NOT under control and dropped straight down from 200 feet. The drone acted like it had no awareness of the it’s altitude and went into landing mode at 200 feet. This was not pilot error but a defect on a brand new product. I can read a flight record and this drone was not under my control within a minute from take off. The altitude reading clearly show a problem with the barometer. I know you can see the -0- altitude readings during the first phase of the flight.

To refuse to honor a warranty on a $1,200 product is outrageous.

 

[Fly Dawg]

At t=02:55s, relative height=63m, flight log cuts off. Pilot commanded roll right while unit is landing. Aircraft flight log cut off, pilot turns off app.

I presume this information came from the aircraft .dat file itself. @2:55 is where the device log ends as the app was shut down or signal was lost. After that we have no way of knowing what they saw to affect the decision. Had we been able to see that file beforehand, I am quite sure that it could be determined otherwise from the analysis of the .dat here. It is a mute point at this time. But I tend to agree that this was not pilot error from the data we have.

 

[sar104]

So I'm getting screwed by DJI( not surprised):
For your case CAS-2313770-X8X3K6, we have finished the analysis, and the result is as follows:

The aircraft was in P-GPS mode and was responsive to pilot command. P mode : P-mode works best when GPS signal is strong. The aircraft utilizes GPS and the vison system to locate itself, stabilize, and navigate between obstacles.

At t=02:55s, relative height=63m, flight log cuts off. Pilot commanded roll right while unit is landing. Aircraft flight log cut off, pilot turns off app.

According to the analysis, the incident was not caused by any product malfunction factors. As such, we could not provide warranty service.We can still proceed with the repairs however, you need to cover the repair fees.

We will have our quotation team to follow up on your case soon.

Your understanding and cooperation will be highly
appreciated.

Once again, sorry for any inconvenience, and thanks for
your support.

My response:

Your facts are incorrect. I have been flying DJI products for 4 years and am well aware of their operation. The drone was NOT under control and dropped straight down from 200 feet. The drone acted like it had no awareness of the it’s altitude and went into landing mode at 200 feet. This was not pilot error but a defect on a brand new product. I can read a flight record and this drone was not under my control within a minute from take off. The altitude reading clearly show a problem with the barometer. I know you can see the -0- altitude readings during the first phase of the flight.

To refuse to honor a warranty on a $1,200 product is outrageous.

They are clearly basing that on the lateral motion of the aircraft while landing. Unfortunately that was caused directly by aileron input. They are ignoring the clear loss of throttle control earlier in the flight which, although it did not directly cause the crash, was certainly a contributing factor.

I would get back to them and clearly point out the throttle problem. However, it was not the vertical motion that directly caused the crash - that was the lateral motion and pilot input that was responsible for that, so it might be tough to convince them.

 

[Deleted member 29014]

They are clearly basing that on the lateral motion of the aircraft while landing. Unfortunately that was caused directly by aileron input. They are ignoring the clear loss of throttle control earlier in the flight which, although it did not directly cause the crash, was certainly a contributing factor.

I would get back to them and clearly point out the throttle problem. However, it was not the vertical motion that directly caused the crash - that was the lateral motion and pilot input that was responsible for that, so it might be tough to convince them.

 

[Deleted member 29014]

"that was the lateral motion and pilot input that was responsible for that, " Except the "lateral motion" occurred at 200 feet. The thing just dropped out of the sky. Appreciated the feedback, I'm screwed.

 

[Deleted member 29014]

I presume this information came from the aircraft .dat file itself. @2:55 is where the device log ends as the app was shut down or signal was lost. After that we have no way of knowing what they saw to affect the decision. Had we been able to see that file beforehand, I am quite sure that it could be determined otherwise from the analysis of the .dat here. It is a mute point at this time. But I tend to agree that this was not pilot error from the data we have.

Thanks. There's no arguing with DJI. They didn't make their money by accepting responsibility.

 

[Fly Dawg]

The thing just dropped out of the sky.

As mentioned before, they are basing this on the aircraft .dat file which we have no way of determining exactly their reasoning without access to that. As Sar104 Mentioned, I would argue the loss of throttle control at a minimum. What do you have to lose other than what you already have.

 

[Deleted member 29014]

As mentioned before, they are basing this on the aircraft .dat file which we have no way of determining exactly their reasoning without access to that. As Sar104 Mentioned, I would argue the loss of throttle control at a minimum. What do you have to lose other than what you already have.

True, nothing to lose.

 

[sar104]

"that was the lateral motion and pilot input that was responsible for that, " Except the "lateral motion" occurred at 200 feet. The thing just dropped out of the sky. Appreciated the feedback, I'm screwed.

Not necessarily. You can argue that the crash occurred because you could not get the aircraft to descend.

 

[Deleted member 29014]

Not necessarily. You can argue that the crash occurred because you could not get the aircraft to descend.

That's what I've been arguing from the start. No one is listening.

 

[Deleted member 29014]

"Thank you for your response.

We totally understand your concern about the result of the analysis. Rest assured that your voice was heard and your case did not go unnoticed . We have created a complaint case for you and have forwarded your case to the complaints team. Right now your case will be re evaluated and rest assured we will check every possible options we can so we can resolve this. Please check your email for updates regarding your case

Should you have questions or clarifications please feel free to contact us."
I await that day with breathless anticipation.
I will be sure to post their final-final answer.

 

[Deleted member 29014]

"Thank you for your response.

We totally understand your concern about the result of the analysis. Rest assured that your voice was heard and your case did not go unnoticed . We have created a complaint case for you and have forwarded your case to the complaints team. Right now your case will be re evaluated and rest assured we will check every possible options we can so we can resolve this. Please check your email for updates regarding your case

Should you have questions or clarifications please feel free to contact us."
I await that day with breathless anticipation.
I will be sure to post their final-final answer.

FINAL RESOLUTION FROM DJI - Screw you, not our fault but we'll sell you another at 30% discount. Go to ( MOD REMOVED ) DJI.