Summary
We propose to supersede Airworthiness Directive (AD) 2015-02- 23, for certain Bombardier, Inc. Model CL-600-1A11 (CL-600), CL-600- 2A12 (CL-601), and CL-600-2B16 (CL-601-3A, and CL-601-3R Variants) airplanes. AD 2015-02-23 currently requires repetitive inspections for fractured or incorrectly oriented fasteners on the inboard flap hinge- box forward fittings on both wings, and replacement of all fasteners if necessary. The preamble to AD 2015-02-23 explains that we consider the requirements interim action and are considering further rulemaking. We now have determined that further rulemaking is indeed necessary, and that replacement of the fasteners is necessary. This proposed AD would require terminating action to replace the fasteners on the inboard flap hinge-box forward fittings on both wings. We are proposing this AD to detect and correct incorrectly oriented or fractured fasteners, which could result in detachment of the flap hinge-box and the flap surface, and consequentreduced controllability of the airplane.