Summary
The FAA proposes to adopt a new airworthiness directive (AD) for all Aerospatiale Model ATR42 airplanes. This proposed AD would require one-time inspections to detect discrepancies (e.g., cracking, loose/sheared fasteners, distortion) of the upper skin and rib feet of the outer wing boxes, and repair if necessary. This proposed AD results from a report of cracking on the upper skin and ribs of the outer wing box on an in-service airplane. We are proposing this AD to detect and correct these discrepancies, which could result in reduced structural integrity of the airplane.