The pilot's maximum climb rate is zero or negative
Stops itArming, disarming and the safety switchCopter only
What ArduPilot says:
- PreArm: Check PILOT_SPD_UP
- PreArm: Check PILOT_SPEED_UP
PILOT_SPEED_UP is the fastest climb the throttle stick can ask for in the modes that hold height (AltHold, Loiter, PosHold), in cm/s: 250 by default, 50 to 500 allowed. It is zero or below, so the copter could never climb in those modes.
What to do, most likely first
It was set to 0 by mistake or by a broken parameter file.
FixSet
PILOT_SPEED_UPto 250.
Parameters to look at
| Parameter | What it is |
|---|---|
PILOT_SPEED_UP | Pilot maximum vertical speed ascending |
Where to do it:Parameter Compare & Migrate
The code that sends it
PreArm: Check PILOT_SPD_UP
ArduCopter/AP_Arming_Copter.cpp AP_Arming_Copter::parameter_checks() · Open in ArduPilot Copter-4.7.1
PreArm: Check PILOT_SPEED_UP
ArduCopter/AP_Arming.cpp AP_Arming_Copter::parameter_checks() · Open in ArduPilot Copter-4.6.3