Airworthiness Directives; The Boeing Company Airplanes

We are superseding airworthiness directive (AD) 2010-20-08, which applied to certain The Boeing Company Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, and 747SR series airplanes. AD 2010-20-08 required repetitive inspections to find cracking of the web, strap, inner chords, inner chord angle of the forward edge frame of the number 5 main entry door cutouts; the frame segment between stringers 16 and 31; repair if necessary; and repetitive inspections for cracking of repairs. This new AD expands the previous fuselage areas that are inspected for cracking. This AD was prompted by multiple reports of cracking outside of the previous inspection areas and a report of a crack that initiated at the aft edge of the inner chord rather than initiating at a fastener location. We are issuing this AD to detect and correct such cracks, which could cause damage to the adjacent body structure and could result in depressurization of the airplane in flight.