Summary
The FAA proposes to adopt a new airworthiness directive (AD) for certain BAE Systems (Operations) Limited Model BAe 146 and Model Avro 146-RJ airplanes. This proposed AD would require modifying the control cable duct on the left bulkhead structure at frame 12, and for certain airplanes, the forward toilet bulkhead structure. This proposed AD results from a structural analysis by the manufacturer which revealed that rapid decompression of the flight compartment with the door closed could cause structural deformation of the left bulkhead structure at frame 12, and of the attached cable duct structure. The duct structure protects the cables for the primary flight controls. We are proposing this AD to prevent deformation of the cable duct structure in the event of a rapid decompression, which could result in restriction of the primary flight controls and consequent reduced controllability of the airplane.