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 inspections to detect cracking of the Hi-lok bolt holes in the main hinge fittings of the horizontal stabilizer, and repair, if necessary. The proposed AD also would require modification of the main hinge fitting, modification or replacement of rib connecting angles, and modification of ribs. This proposal is prompted by a report that cracking was found in the main hinge fittings of the horizontal stabilizer during fatigue testing. The cracking was a result of higher-than-anticipated loads induced during operation of the thrust reverser. The actions specified by the proposed AD are intended to prevent deterioration of the fatigue life of the main hinge fittings of the horizontal stabilizer and reduced structural integrity of the horizontal stabilizer due to higher induced loads.