Summary
The FAA is revising an earlier NPRM for an airworthiness directive (AD) that applies to all Airbus Model A310 series airplanes and Model A300-600 series airplanes. The original NPRM would have required superseding two existing ADs. One existing AD applies to certain Airbus Model A310 series airplanes and currently requires repetitive inspections for cracking of the flap transmission shafts, and replacement of the transmission shafts if necessary. That existing AD also provides an optional terminating action for the repetitive inspections. The other existing AD applies to all Airbus Model A310 and A300-600 series airplanes and currently requires a one-time inspection of the trimmable horizontal stabilizer actuator, corrective actions if necessary, and follow-on repetitive tasks. The original NPRM would have added revising the Airworthiness Limitations Section of the Instructions for Continued Airworthiness to incorporate new limitations and maintenance tasks for aging systems maintenance. The original NPRM resulted from the manufacturer's determination that life limitations and maintenance tasks are necessary in order to ensure continued operational safety of the affected airplanes. This new action revises the original NPRM by reducing the initial compliance times. We are proposing this supplemental NPRM to prevent reduced structural integrity of these airplanes due to the failure of system components.