Summary
We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as: Two operators of A300 aircraft fitted with General Electric (GE) CF6-50 engine series have reported cracks on the lower side of Rib 5 in the pylon box. Investigations disclosed that these cracks are due to the stresses resulting from the pressure applied by the thrust reverser cowl bumpers. Cracking of the engine pylons could result in reduced structural integrity of the engine support structure. The proposed AD would require actions that are intended to address the unsafe condition described in the MCAI.