Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to all Raytheon Model BAe.125 series 1000A and 1000B airplanes and Model Hawker 1000 series airplanes. This proposal would require an inspection to determine the integrity of the duct connection on both ends of the turbine air discharge duct in the air conditioning system, an inspection to measure the bead height on the ends of the turbine air discharge duct; and corrective actions, if necessary. This proposal is prompted by reports indicating that the turbine air discharge duct disconnected from the cold air unit (CAU) or water separator due to insufficient bead height on the ends of the turbine air discharge duct. The actions specified by the proposed AD are intended to prevent such disconnection from the CAU or water separator, which could result in cabin depressurization.