Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to all BAE Systems (Operations) Limited Model BAe 146 series airplanes. This proposal would require repetitive detailed inspections of the inside of each air conditioning sound-attenuating duct, and corrective actions as necessary. This action is necessary to prevent impairment of the operational skills and abilities of the flightcrew caused by the inhalation of agents released from oil or oil breakdown products, which could result in reduced controllability of the airplane. This action is intended to address the identified unsafe condition.