PRODUCT: Boeing Model 717-200 airplanes. SUBJECT: Airworthiness Directive 2012-12-09 ACTION: Final Rule
SUMMARY: This AD was prompted by reports of cracks found on the center section ribs of the horizontal stabilizers. This AD requires repetitive inspections for cracking of the aft face of the left and right rib hinge bearing lugs of the center section of the horizontal stabilizer; and crack measurement, repairs, post-repair repetitive inspections, and installation of a new center section rib if necessary. The FAA is issuing this AD to detect and correct cracking in the left and right bearing lugs of the rib hinge spreading at the same time, which could result in failure of both hinge bearing lugs.
Failure of the hinge bearing lugs could result in the inability of the horizontal stabilizer to sustain flight loads and thereby reduce the controllability of the airplane.