The Federal Aviation Administration (FAA) has issued an airworthiness directive for specific Boeing 757 models following concerns over potential cracks in the upper frame. This decision comes after a crack growth analysis suggested that current inspection methods might not be sufficient to detect issues before a single frame failure occurs.
"The NPRM was prompted by a crack growth analysis, which indicated that current inspections are not adequate to detect cracks in certain sections of the upper frame at the frame splice between certain stringers before a single frame fails," stated the FAA.
The directive mandates inspections of existing repairs and repetitive checks of the upper frame at specific splices, with additional actions required if issues are found. A supplemental notice proposed revised inspection intervals for freighter-converted 757-200s by Aviation Partners Boeing (APB).