Airworthiness Directive · Amendment 39-9057 · The Boeing Company Airplanes
The Boeing Company Airplanes
This AD applies to The Boeing Company 747-100 Series, 747-100B Series, 747-100B SUD Series, 747-200B Series, 747-200C Series, 747-200F Series, 747-300 Series, 747-400 Series, 747-400D Series, 747-400F Series, 747SP Series, 747SR Series.
The models as the FAA's AD index lists them. The serial ranges, installed parts and exceptions are in the AD itself: read it at the FAA.
This amendment supersedes an existing airworthiness directive (AD), applicable to certain Boeing Model 747 series airplanes, that currently requires inspections of the strut skin in the area of the precooler exhaust vent for cracks on the inboard and outboard struts, and repair, if necessary. This amendment requires inspections of an expanded area for certain airplanes, and inspections of airplanes on which a skin doubler has been installed as terminating action for the existing AD. This amendment is prompted by reports of strut skin fatigue cracks and heat damage found aft of the edges of skin doublers installed on certain Model 747 series airplanes. The actions specified by this AD are intended to prevent separation of an engine due to overheating and subsequent cracking of the engine strut.
