DJI Drone Help Forum

Help, Spark sent out into the sea, flightrecord analys

Hello

I was flying my almost new DJI Spark in Mexico CanCun outside Hotel Hyatt Ziva and on 35m altitude I got alot of errors and warnings and suddenly the DJI Spark flew out in the water and got lost. I believe the DJI Spark had som serious malfunction bug and I am looking to get it replaced even though it is lost in the water and I have no insurance.

Is there any good flight record anlaysits out there that could give your opinion? I hered that this happened more people in Mexico and that it seems that they invented a technology to cut you signal and overtake the ride and kill the drone out in the sea.

I uploaded the flght record txt
https://www.phantomhelp.com/LogViewer/30ASZTIDYB3HYI24J8RW/

Below I will tell you my experience and aswell write all kind of error massages I got. I flew it with a new DJI controller L100A

Errors in iphone XS:

  • IMU heading error. Please restart aircraft (about 1-2 min in at approx 35min hovering above myself connected to 16 GPS)
  • Compass Error. Exit P-GPS Mode (I did not push anything for this to appear, I was just hoovering above myself 30m same as Home Point)
  • Weak GPS signal. Position accuracy can be compromised. Please fly with caution.
  • IMU heading error. Please restart the aircraft. (stil 30m above myself with “full” charged batteries)
  • Weak GPS signal (stil shows 16 satelites on display) - Starts to drift rapidly out into the sea 35km/h horizontal speed alo slowly descends 2km/s
  • Abnorml compass function or GPS signal detected. Aircraft switched to ATTI mode.

Error in the flight record online analys

  • Yaw Error
  • Compass Error
  • Abnormal compass function or GPS signal detected. Aircraft switched to ATTI mode.; Yaw Error
  • Downlink Restored (after 0m 3.1s); Abnormal compass function or GPS signal detected. Aircraft switched to ATTI mode.; Yaw Error
  • Downlink Restored (after 0m 0.9s); Yaw Error
  • Weak GPS signal. Positional accuracy may be compromised. Please fly with caution.; Yaw Error
  • Compass Error. Exit P-GPS Mode; Yaw Error

When it started to drift out into the sea at approx 20m it suddenly lost all connection to the phone at only about 50m distans and drifted out sideways and just keep disappearing. I did not believe the flight record kept recording since I could not se any more info in my DJI GO4 app. It just showed te drone was above me but stoped showing it drifting away but the flight record seems to have recorded it all the way where it decent in the water even though I had zero connection and no picture on screen.

These are your primary issues. The compass error occurred early on in the flight at~68 seconds. The aircraft switched to ATTI as it is designed to do with a compass error. What I am not understanding however it does appear you had connection all the way in to the water. The oddity is either you were giving stick inputs ( Both sticks ) at ~100 seconds, something is wrong with this data, or there is another issue that I am not seeing here initially. All the stick inputs at ~100 seconds went to basically 50 percent. Something doesn’t look right there. Maybe @sar104 can give you a better explanation of that.

@Andein Below is my reference to stick inputs. I find it hard to believe that all 4 could be that close together for the remainder of the flight by your inputs. Did you lay the controller down or something? If not, then it could be a controller issue as well as an aircraft issue.

We’ll definitely need the .DAT for this one. Please retrieve it from your tablet using these instructions.
Retrieving a V3.DAT from the tablet

When the Spark was at 30 m at the home point above you was it rotating?

@BudWalker Most curious on this. Any idea about the incident between ~98 and 100.3 sec?
Or am I just missing something? Yes more data would help, but what is your guess?

Not sure that it’s an incident. Maybe so. Looks more like the controls didn’t move and the Spark responded normally to those stuck control inputs.

@Andein the reason that I asked about the Spark rotating is that although Yaw was constant the Spark was pitching and rolling with a period of about 5 secs with pitch and roll about 90° degrees phase difference. This would be the case if the Spark were rotating in the wind and needed to pitch and roll to remain stationary. In the situation where there is a Yaw/magYaw separation the FC will often try to reconcile that by rotating the AC while holding the Yaw value constant until that constant Yaw equals the magYaw.

That is what I was thinking as well. I mentioned “incident” just to point out where the odd difference occurred. That is unusual to have inputs “stuck” as those appeared to be, which is also why I mentioned that the OP possibly laid the controller down ( Upside down ) and that moved the sticks to where they were. I don’t see any other way that all 4 signals would remain that way otherwise, unless there was some sort of RC issue, or some sort of transmission issue, which doesn’t appear to be the case. We will see if the OP provides the additional data. Without those stick inputs, the OP could have possibly recovered. Maybe so, maybe not.

The stuck inputs are odd. With a disconnect I’d expect the control inputs to go to 0. And, they do vary just a little. Maybe you’re right and the RC was lodged or otherwise stuck against something.