[5] ArduCopter PL Parameters
Precision Landing EKF Settings
We recommend turning off the precision landing EKF by setting the parameter PLND_EST_TYPE to 0.
Precision Landing I2C Bus
Choose the appropriate I2C bus by modifying the PLND_BUS parameter.
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Precision Landing parameters
ArduCopter Precision Landing Docs:
http://ardupilot.org/copter/docs/precision-landing-with-irlock.html
Updated less than a minute ago