Troubleshooting

General Warnings

Symptom	Potential Cause	Potential Solution
Boot Fail	Voltage limits exceeded	Check voltage of flight packs and replace as necessary
Compass readings out of limits	Check surroundings and boot in an area away from ferrous objects. Recalibration of the compass.
Compass Warning	Invalid compass calibration	Calibrate the compass
GPS Warning	GPS/Compass Unit has become disconnected	Check the GPS/Compass unit wiring for damage
Accelerometer Warning	Hard landing	Reboot ALTA Pro
Motor Warning	ESC or Motor failure or error	Contact Freefly Customer Support immediately. Do not continue flying ALTA Pro.

Flight Controller

Symptom	Potential Cause	Potential Solution
ALTA Pro will not arm	Radio not bound	Follow radio controller manufacturer’s binding procedure
	Radio not mapped properly	Check radio mapping charts for correct behavior. Adjust mapping as necessary in ALTA Pro QGroundControl
	Flight Controller boot not successful	Power cycle ALTA Pro. Ensure it does not move during boot If ALTA Pro must move during boot (such as on a moving platform), use Motion Booting
	Low Battery	A low battery error latches and does not allow further take off without a battery replacement.

Flight Behavior

Symptom	Potential Cause	Potential Solution
Unexpected flight behavior	Tuning too high or too low	Revert tuning to the last known working configuration Set tuning back to default values
Alta Pro seems to "hop" or "dip" at the end of a climb	Hover throttle not set correctly	Change hover throttle to match weight of aircraft. 49% for ~10lb payload, closer to 40% for light aircraft.
ALTA Pro does not maintain level pitch or roll	Pitch or Roll Trim position not set	Use the ALTA app to set the appropriate pitch and roll trim
ALTA Pro oscillates or vibrates during flight	Tuning too high or too low	Check flight settings and tuning parameters in the App. Revert tuning to the last known working configuration. Re-tune.
	Propellor Damage	Check for damage to propeller blades. Replace with spares as required.
	Propeller blades unbalanced	Replace with spares as required. Propeller blades are balanced and matched at the factory.
	Hinge or motor misalignment	Thoroughly inspect ALTA Pro following any accident. Contact Freefly for further inspection and assessment.
	Ice on Propellers	Ice build-up is causing vibrations due to unbalanced propellers. Remove ice from propellers before further flights.
ALTA Pro is sluggish in response to commands	Tuning too low	Check tuning in ALTA Pro and adjust as required
	Flight weight is over limit	Weigh the ALTA Pro and compare to the Allowable Gross Weight table in this manual. Remove weight.
ALTA Pro ascends or descends when switching between flight modes	Hover Throttle set incorrectly	Follow the instructions listed in the ALTA Pro Flight Parameters section of this manual to adjust Hover Throttle
ALTA Pro does not maintain heading	Yaw during boot	Re-initialize ALTA Pro while keeping ALTA Pro stationary in all directions
Unexpected behavior in Position Mode	Position lock not achieved	Monitor ALTA Pro QGroundControl and takeoff only after Position Lock has been achieved with strong GPS signal
	Incorrect heading due to yaw during boot	Re-initialize ALTA Pro while keeping ALTA Pro stationary in all directions
	Compass corruption or calibration	Check surroundings for ferrous objects or magnetic interference. Calibrate the compass.
ALTA Pro circles a point in Position Mode	Compass calibration is invalid	Calibrate the compass
	Position tuning values too high	Reduce Position tuning values very slightly following the PX4 tuning guide.
ALTA Pro does not track straight in Position Mode	Compass calibration invalid	Perform a manual compass calibration.
ALTA Pro does not Return-to-Land when commanded	Position Lock not achieved	Monitor the ALTA Pro QGroundControl to ensure position lock has been achieved with strong GPS signal
ALTA Pro wobbles when descending	Vertical descent into turbulent air from propellers	Descend at a slight angle relative to vertical so the ALTA Pro does not fly into turbulent air from propeller downwash