Action
Notice of proposed rulemaking (NPRM).
Summary
We propose to supersede Airworthiness Directive (AD) 2013-02- 08, for all Bombardier, Inc. Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes. AD 2013-02-08 currently requires inspecting the trunnions and upper and lower pins of the horizontal stabilizer trim actuator (HSTA), and replacement or re-identification if necessary; and revising the maintenance program to include safe life limits and inspection requirements for the HSTA. Since we issued AD 2013-02-08, we determined that not all affected attachment pins and trunnions were included in the required inspections. In addition, for certain airplanes on which the replacement in AD 2013-02-08 was done, incorrect attachment hardware may have been used. This proposed AD would require measuring the diameter of certain bolts and attach holes, and, as applicable, measuring the diameter of the attach holes in the trunnions and pins, doing detailed visual inspections of the trunnions, pins, and spacers, doing corrective actions, and re-identifying trunnions and pins. This proposed AD also requires revising the maintenance or inspection program. This proposed AD also removes certain airplanes from the applicability. We are proposing this AD to prevent failure of the attachment pins and trunnions of the HSTA. This condition could result in separation of the horizontal stabilizer, and consequent loss of control of the airplane.