Summary
We are revising an earlier NPRM for the products listed above. This proposed AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:
It has been found that moisture may accumulate and freeze, under certain conditions, in the gap between the AOA vane base assembly and the stationary ring of the sensor's body. If freezing occurs both AOA sensors may get stuck and the Stall Warning Protection System (SWPS) will be no longer effective without alerting. This may result in inadvertent aerodynamic stall and loss of controllability of the airplane.
The proposed AD would require actions that are intended to address the unsafe condition described in the MCAI.