Hi all,
We operate a fleet of agricultural spraying drones with 1000+ flights across multiple units using identical FC, firmware, and parameters. One new production drone is showing aggressive, unpredictable, uncontrollable flight behavior that has resulted in attitude flips and a crash. Attaching multiple logs from the same drone.
Issue summary:
-
Drone suddenly enters aggressive erratic flight with no pilot input
-
Attitude flipped twice across different flights
-
In some flights, switching to Stabilize mode recovered control — but not always
-
In other flights, no mode switch helped — drone was completely unresponsive to pilot input
-
Ended in a crash
-
Behavior is unpredictable — no consistent trigger point
What we’ve already swapped (issue persists on same airframe):
-
Flight controller replaced → still erratic
-
GPS replaced → still erratic
-
Motors replaced → still erratic
-
PDB and RC radio unchanged (same as working drones)
Key observation: Issue follows the airframe, not any single component — even after replacing FC, GPS, and motors, this specific drone still misbehaves.
Fleet comparison:
| Working drones | Problem drone | |
|---|---|---|
| Firmware | ArduCopter [version] | Same |
| Parameters | Fleet param file | Same |
| FC | CubeOrange+ | CubeOrange+ (different batch) |
| GPS | Same model | Different batch |
| Motors | Same model | Different batch |
| PDB | Same | Same |
| Radio | Same | Same |
Attached: Multiple .bin logs from the same drone across different flights (including crash flight)
Requesting the community’s help to identify the root cause from the logs. We have exhausted component swaps and the issue persists on this specific airframe. What does the log data point to?
FC: CubeOrange+ | Firmware: ArduCopter [4.6.0] | Frame: [Hexa] agri sprayer