Summary
The FAA proposes to adopt a new airworthiness directive (AD) for all EMBRAER Model ERJ 170 airplanes. This proposed AD would require revising the Airworthiness Limitations section (ALS) of the airplane maintenance manual (AMM) to include new, specific maintenance tasks related to the incorporation of a new horizontal stabilizer actuator. This proposed AD also would require revising the ALS of the AMM to include revised repetitive inspection intervals for certain tasks in the maintenance plan related to the aileron and flap/slat flight controls system. This proposed AD results from safety assessments of the aileron and flap/slat flight controls system, conducted after the type certification of the airplane, which showed that some dormant faults did not comply with the safety assessment criteria. We are proposing this AD to prevent failure of the aileron and flap/slat controls system, which could result in reduced controllability of the airplane.