Airworthiness Directives; General Electric Company (GE) CT7-9C and -9C3 Turboprop Engines

We are adopting a new airworthiness directive (AD) for the products listed above. This AD requires inspecting certain serial number (S/N) gas generator turbine (GGT) shafts for nonconforming land balance-cuts, and if found, removing the shaft from service. This AD was prompted by reports of a manufacturing quality problem. We are issuing this AD to detect nonconforming GGT shaft land balance-cuts, which could result in the shaft failing before its published life limit, and which could result in an uncontained engine failure and damage to the airplane.