AD NUMBER: 2006-03-13
MANUFACTURER: McDonnell Douglas
SUBJECT: Airworthiness Directive 2006-03-13
SUMMARY: The FAA is adopting a new airworthiness directive (AD) for certain McDonnell Douglas transport category airplanes. This AD requires an initial ultrasonic inspection for cracks of the stud bolts of the inboard and outboard hinge fittings of the left and right outboard flaps of the wings. Based on the inspection results, this AD also requires doing repetitive ultrasonic inspections, replacing upper and/or lower stud bolts with new or serviceable stud bolts, doing a detailed inspection for corrosion of the upper stud bolts, doing a magnetic particle inspection for cracks of stud bolts, and changing the protection treatment; as applicable. This AD results from reports of corrosion and failures of the upper and lower stud bolts of the outboard flaps inboard and outboard hinge fittings. We are issuing this AD to prevent corrosion and subsequent cracking of stud bolts, which could result in failure of the flap hinge fittings and their possible separation from the wing rear spar, and consequent reduced controllability of the airplane.

FMI: www.faa.gov/regulations_policies/airworthiness_directives/