Summary
We propose to supersede Airworthiness Directive (AD) 2012-16- 08, for certain BAE Systems (Operations) Limited Model BAe 146 and Avro 146-RJ series airplanes. AD 2012-16-08 currently requires repetitive detailed inspections for bulging, surface anomalies, and cracking of the fuselage skin adjacent to the discharge valves, and repair and application of additional sealant in the affected area if necessary. Since we issued AD 2012-16-08, it was found that airplanes on which a certain modification was incorporated during production were excluded from the applicability, but are also affected by the condition that precipitated AD 2012-16-08. This proposed AD would retain the requirements of AD 2012-16-08, expand the applicability, and require an additional one-time inspection for the presence of water traps/air driers to determine which airplanes must be inspected. We are proposing this AD to detect and correct bulging, surface anomalies, and cracking that could propagate towards the forward discharge valve outlet and result in the failure of the fuselage skin, leading to a possible sudden loss of cabin pressure and injury to occupants.