Airworthiness Directives; Airbus Model A300 B2 and B4 Series Airplanes; and Model A300 B4-601, B4-603, B4-605R, B4-620, B4-622R, C4-605R Variant F, and F4-605R Airplanes

This amendment supersedes an existing airworthiness directive (AD), applicable to certain Airbus Model A300 B2 and B4 series airplanes, and Model A300 B4-601, B4-603, B4-605R, B4-620, B4-622R, C4- 605R Variant F, and F4-605R airplanes, that currently requires a one- time inspection for cracking of the gantry lower flanges in the main landing gear (MLG) bay area; and repair, if necessary. This amendment removes an airplane model from the applicability. This amendment, for certain airplanes, retains the one-time inspection for cracking of the gantry lower flanges and repair, if necessary. For other airplanes, this amendment adds repetitive inspections of the gantry lower flanges; repair, if necessary; and reinforcement of the left-hand and right-hand gantry. The actions specified by this AD are intended to detect and correct cracking of the gantry lower flanges in the MLG bay area, which could result in decompression of the airplane. This action is intended to address the identified unsafe condition.