The ground station link is lost right now
What ArduPilot says:
- PreArm: GCS failsafe on
The ground station failsafe is on (FS_GCS_ENABLE is not 0), a ground station was heard at least once since power-on, and its heartbeat has now been missing for longer than FS_GCS_TIMEOUT (5 s by default). The copter would be in failsafe the moment it armed, so it refuses. Only the ground station whose system ID is SYSID_MYGCS (255 by default) counts.
What to do, most likely first
The ground station was closed, or the telemetry radio or cable was unplugged.
FixConnect the ground station again: the failsafe clears as soon as its heartbeat is back.
You connected over USB to set something up and unplugged; the copter still waits for that ground station.
FixReboot the flight controller: a ground station that was never heard since power-on is not waited for.
You fly without a ground station, and the failsafe was switched on by a parameter file.
FixDecide with the Failsafe Explainer whether you want this failsafe; it is meant for flights that depend on the telemetry link.
Parameters to look at
| Parameter | What it is |
|---|---|
FS_GCS_ENABLE | Ground Station Failsafe Enable |
FS_GCS_TIMEOUT | GCS failsafe timeout |
SYSID_MYGCS | My ground station number |
Where to do it:Failsafe ExplainerSetup & Tuning Guide
The code that sends it
PreArm: GCS failsafe on
ArduCopter/AP_Arming.cpp AP_Arming_Copter::gcs_failsafe_check() · Open in ArduPilot Copter-4.6.3
ArduCopter/AP_Arming_Copter.cpp AP_Arming_Copter::gcs_failsafe_check() · Open in ArduPilot Copter-4.7.1