Airworthiness Directives; British Aerospace Model BAe 146-100A, - 200A, and -300A Series Airplanes Equipped With AlliedSignal ALF502R- Series Engines

This amendment supersedes an existing airworthiness directive (AD), applicable to all British Aerospace Model BAe 146-100A, -200A, and -300A series airplanes, that currently requires installation of a placard prescribing special procedures to be followed when operating at certain flight levels with the engine and airframe anti-ice switch ON; modification of the air brake auto-retract function; and a revision to the Airplane Flight Manual (AFM) relative to altitude and operating limitations associated with flight in icing conditions above 26,000 feet. This amendment requires installation/replacement of new placards. This amendment also provides for a terminating modification for the AFM revision and installation/replacement of placards. This amendment is prompted by reports of uncommanded engine thrust reductions (rollback) when operating in certain icing conditions that exist in the vicinity of thunderstorms. The actions specified by this AD are intended to prevent engine power rollback during flight in icing conditions, a condition that could result in insufficient power to sustain flight.