Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to all Fokker Model F.28 Mark 1000, 2000, 3000, and 4000 series airplanes. This proposal would require a one-time eddy current inspection for cracks of the fuselage butt joint which is forward of the emergency exits on the left-and right-hand sides of the airplane at the level of stringers 27/48. This proposal would also require repair of any cracks detected. This action is prompted by issuance of mandatory continuing airworthiness information by a foreign airworthiness authority. This action is necessary to detect and correct cracks in the area of the emergency escape hatches, which, if undetected, could result in depressurization during flight, possibly leading to structural failure of the airplane. This action is intended to address the identified unsafe condition.