Summary
We propose to adopt a new airworthiness directive (AD) 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 determined that the surface roughness of the wing stub safety walks Series 300, gray color (equals sandpaper grid 40), installed during production on some aeroplane S/Ns, adversely affects the aircraft single engine climb performance.
The proposed AD would require actions that are intended to address the unsafe condition described in the MCAI.