Airworthiness Directives; Fokker Model F28 Mark 0100 Series Airplanes

摘要

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Fokker Model F28 Mark 0100 series airplanes. This proposal would require a one-time operational test of the No. 1 pitot heating system, and repair or replacement of failed elements. This AD also would require modification of certain electrical wiring, and replacement of the pitot head and a certain relay. This proposal is prompted by reports indicating that the No. 1 Air Data Computer (ADC #1) failed due to icing of the No. 1 pitot tube. The actions specified by the proposed AD are intended to prevent icing of the No. 1 pitot tube, which could result in failure of the No. 1 ADC or output of erroneous airspeed data to all on-side subsidiary systems including the Automatic Flight Control and Augmentation System (AFCAS).