DJI Phantom 4 Malfuntion - Climbed On Its Own, Would Not Descend

[Fly Dawg]

Absolutely.... My intent was simply to assist you in clarifying your, as stated, untested assumption.

Interesting. Good someone has tested this. It has been a curious entity at times. The reason I questioned it was not only have I not tested that, it was from several data sets I have looked at that do not show an initiated RTH in ATTI mode. Maybe this is a data anomaly, or dependent upon multiple mode switching during an unanticipated event.

 

[Meta4]

Interesting. Good someone has tested this. It has been a curious entity at times. The reason I questioned it was not only have I not tested that, it was from several data sets I have looked at that do not show an initiated RTH in ATTI mode. Maybe this is a data anomaly, or dependent upon multiple mode switching during an unanticipated event.

It makes perfect sense for RTH to work if the Phantom has GPS reception.
It would be pointless for the programmers to leave a Phantom drifting on the wind and refusing to RTH.
If you are flying in atti mode and press the RTH button or lose signal and the Phantom initiates RTH, the Phantom doesn't stay in atti mode.
Regardless of the position of the flight mode switch, the Phantom switches to RTH mode which is a different flight mode.

 

[Fly Dawg]

It makes perfect sense for RTH to work if the Phantom has GPS reception.
It would be pointless for the programmers to leave a Phantom drifting on the wind and refusing to RTH.

Exactly my point in relation to this particular incident, however, this did not occur as initiated by the OP, apparently due to the stuck throttle from the RC. One would think that in a scenario such as this, RTH would have overridden the RC command for full throttle and the AC would have initiated the return ( which in this instance it did at one point), and negated the full throttle RC command. This did not happen. Even though RTH was commanded both by the pilot and by smart battery, the AC never descended for landing due to the RC commanding full throttle. This was where my question of ATTI mode RTH originated.

 

[Meta4]

Exactly my point in relation to this particular incident, however, this did not occur as initiated by the OP, apparently due to the stuck throttle from the RC. One would think that in a scenario such as this, RTH would have overridden the RC command for full throttle and the AC would have initiated the return ( which in this instance it did at one point), and negated the full throttle RC command. This did not happen. Even though RTH was commanded both by the pilot and by smart battery, the AC never descended for landing due to the RC commanding full throttle. This was where my question of ATTI mode RTH originated.

RTH did work to bring the Phantom back to above the home point.
The controller malfunction had the same effect as manually pushing the left stick full forward, which would also prevent descent.
Until the error in the controller malfunction was cleared (or if the OP had switched off the controller) the Phantom wasn't coming down (until the battery gave up).

 

[captainmilehigh]

RTH did work to bring the Phantom back to above the home point.
The controller malfunction had the same effect as manually pushing the left stick full forward, which would also prevent descent.
Until the error in the controller malfunction was cleared (or if the OP had switched off the controller) the Phantom wasn't coming down (until the battery gave up).

That was my thinking at the beginning of this thread. Turn off the R/C and let the bird do what it is supposed to do. But as stated in previous posts, the OP had no idea of the throttle issue being ‘stuck’.

It’s good to know however that the bird will automatically jump from ATTI back to GPS on loss of signal. Old dog learned new trick.

 

[With The Birds]

It makes perfect sense for RTH to work if the Phantom has GPS reception.
It would be pointless for the programmers to leave a Phantom drifting on the wind and refusing to RTH.
If you are flying in atti mode and press the RTH button or lose signal and the Phantom initiates RTH, the Phantom doesn't stay in atti mode.
Regardless of the position of the flight mode switch, the Phantom switches to RTH mode which is a different flight mode.

Thank your Meta...... that’s what I thought I had said....

 

[sar104]

Interesting. Good someone has tested this. It has been a curious entity at times. The reason I questioned it was not only have I not tested that, it was from several data sets I have looked at that do not show an initiated RTH in ATTI mode. Maybe this is a data anomaly, or dependent upon multiple mode switching during an unanticipated event.

It depends on the origin of the ATTI mode. If it is switched on the controller, rather than switched by the FC due to IMU yaw / magnetic yaw discrepancies, then it can RTH just fine, and the RTH command or uplink loss is effectively assumed to override the user-selected ATTI mode, putting it back into P-GPS. I've tested it too, although only on the Mavic Pro.

 

[With The Birds]

It depends on the origin of the ATTI mode. If it is switched on the controller, rather than switched by the FC due to IMU yaw / magnetic yaw discrepancies, then it can RTH just fine, and the RTH command or uplink loss is effectively assumed to override the user-selected ATTI mode, putting it back into P-GPS. I've tested it too, although only on the Mavic Pro.

Yes- I was referring to instances where the AC has GPS lock (P-GPS would function normally should the operator switch out of ATTI). I have tested in P3, P4 and P4P... when I say tested I normally fly in ATTI when I’m on the sticks and have satisfied myself the RTH command works as expected on all AC’s. For me ATTI flight gives smoother video than P-GPS.

 

[sar104]

Yes- I was referring to instances where the AC has GPS lock (P-GPS would function normally should the operator switch out of ATTI). I have tested in P3, P4 and P4P... when I say tested I normally fly in ATTI when I’m on the sticks and have satisfied myself the RTH command works as expected on all AC’s. For me ATTI flight gives smoother video than P-GPS.

Agreed - that's what I understood you meant.

 

[lasersbee]

As the flight logs show (after the fact) the controller was connected
to the Drone. It was sending (not known then) erroneous throttle
input data and it would continue to do so. The drone thinking the
operator was inputting 100% Throttle data, complied.

Once the controller is turned 'OFF' and the link is broken the Drone
would no longer receive that erroneous Throttle data or Atti-P-S switch
data and go into Lost Signal RTH as long as the Home point had been
recorder and GPS data was still available...

Turning 'OFF' the controller seems to be the thing to do if all other
options have been exhausted and you are still not in controll... IMO

 

[gerickson9301]

DJI refuses to do anything to help me. All they have offered me is a 10% discount on a new drone purchase through them. I filed a complaint with DJI and spoke with one of their managers last night who told me their decision is final and they will NOT review my flight logs or open a case for me.

I asked them if I could pay them money to have them review my flight logs and they told me that this is not possible.

It is very upsetting that since the drone is over 1 year old they simply turn their back on their customers when their product clearly has a malfunction.

 

[Northern Canadian]

Strong case to review your maximum altitude settings. In Canada if above 400 feet you are on the bad guy list. This whole scenario is really quite unsettling. Good it ended relatively well with no injury or property damage.

 

[Pharm]

Just curious. Is it possible to go into the settings and change the inputs so they are reversed (i.e., when one thinks they’re commanding a descent but they’re actually commanding an ascent)?

 

[captainmilehigh]

DJI refuses to do anything to help me. All they have offered me is a 10% discount on a new drone purchase through them. I filed a complaint with DJI and spoke with one of their managers last night who told me their decision is final and they will NOT review my flight logs or open a case for me.

I asked them if I could pay them money to have them review my flight logs and they told me that this is not possible.

It is very upsetting that since the drone is over 1 year old they simply turn their back on their customers when their product clearly has a malfunction.

Hate to hear bad news. Sorry DJI will only do a 10% discount too. I was hoping they would at least consider it an issue and offer a better solution.

Since the R/C may have been at fault, you might consider replacing it also if you find another bird. Wouldn’t want this issue to repeat itself.

Even if you recover the bird, it may be in bad shape due to a free fall from that altitude at terminal velocity.

We here at the Forum hope you get back to flying very soon. [emoji106]

 

[captainmilehigh]

Just curious. Is it possible to go into the settings and change the inputs so they are reversed (i.e., when one thinks they’re commanding a descent but they’re actually commanding an ascent)?

There are settings in DJI GoApp that allows you to change sides, as well as a custom setting that allows changes to suit the operator.

Haven’t tried any of them personally. I’m afraid I’ll screw something up. Flies too good to risk it.