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:
At some locations, the new calculated fatigue life [for the wing to center box assembly] falls below the aircraft Design Service Goal.
The aim of this Airworthiness Directive (AD) is * * * to ensure detection of cracks on the panels and stiffeners at rib No. 1. This situation, if left uncorrected, could affect the structural integrity of the area.
The proposed AD would require actions that are intended to address the unsafe condition described in the MCAI.