Airworthiness Directives; CFM International S.A. Turbofan Engines

We are adopting a new airworthiness directive (AD) for certain CFM International S.A. (CFM) CFM56-3, -3B, and -3C turbofan engines. This AD was prompted by a report of dual-engine loss of thrust control (LOTC) that resulted in an air turn back. This AD requires initial and repetitive checks of the variable stator vane (VSV) actuation system in the high-pressure compressor (HPC). We are issuing this AD to address the unsafe condition on these products.