AD NUMBER: 2008-24-12
MANUFACTURER: Bombardier
SUBJECT: Airworthiness Directive 2008-24-12
SUMMARY: We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as: During scheduled maintenance inspection, a bolt which connects the PCU (power control unit) to the elevator surface was found fractured in the assembly. Further inspection of the assembly revealed that the bearing on the PCU rod end had seized, which resulted in damage to the attachment fitting bushing and fracture of the bolt.Inspection of other in-service airplanes revealed two more seized PCU attachment joints.However, except seizure, no fractured bolt was found on these airplanes. Failure of the bolts in both PCUs on one side could result in disconnection of the elevator control surface which would lead to flutter and loss of the aircraft. * * * * * This AD requires actions that are intended to address the unsafe condition described in the MCAI.

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