Airworthiness Directives; Fokker Model F28 Mark 0070 and Mark 0100 Series Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Fokker Model F28 Mark 0070 and Mark 0100 series airplanes, that requires a one-time visual inspection to detect heat damage of the fuselage skin and stubwing structure. This proposal also would require either repetitive leak tests of the seals of the bleed air system, or repair of any heat-damaged structure, as necessary; and replacement of corrujoint seals with new improved seals. This amendment is prompted by the issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent the leakage of hot air from the corrujoint seals of the low- and high-pressure check valves located in the stubwings, which could result in heat damage to the fuselage skin and stubwing structure, and consequent reduced structural integrity of the airplane.