# 3.7. Preflight inspection
### Click the "Pre-flight inspection" button to open the pre-flight inspection interface.
#### 3.7.1. Power on the other four batteries for rotor motors.
#### 3.7.2. airspeed calibration.
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The two of them cooperated and performed airspeed calibration according to the prompts.
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#### 3.7.3. Motor test.
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Check the motor rotation one by one manually, make sure the motors on the drone rotates direction is the same as the in the software screen.
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#### 3.7.4. Mode test
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Follow the instructioins in "Mode test" menu to check the servo control sufrace response in both Manual mode and FBWA mode.
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#### 3.7.5. Ground station mode switching check
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Click the ground station mode command button in sequence and observe whether the mode switching is normal.
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#### 3.7.6. Check drone status.
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Check if the GPS status, video\&data link signal, battery voltage,fuel remaining, heading direction are normal from ground control software, check if there is any warning.
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