Airworthiness Directives; GE Aviation Czech s.r.o. (Type Certificate Previously Held by WALTER Engines a.s., Walter a.s., and MOTORLET a.s.) Turboprop Engines

The FAA is adopting a new airworthiness directive (AD) for certain GE Aviation Czech s.r.o. (GEAC) M601D-11, M601E-11, M601E-11A, M601E-11AS, M601E-11S, and M601F model turboprop engines. This AD was prompted by the absence of life limits for propeller shaft part number (P/N) M601-6081.6 in the airworthiness limitations section (ALS) of the applicable GEAC M601 Engine Shop Manual. This AD was also prompted by a report that operators may not have been provided with enough data to determine the accumulated life of certain propeller shafts. For M601F model turboprop engines, this AD requires removal and replacement of the propeller shaft before the propeller shaft accumulates 12,000 flight hours (FHs) since first installation on an engine, or before accumulating 350 FHs after the effective date of this AD, whichever occurs later, with a part eligible for installation. For M601D-11, M601E-11, M601E-11A, M601E-11AS, and M601E-11S model turboprop engines, this AD requires calculation of the accumulated life of the propeller shaft and, depending on the number of accumulated FHs removal and replacement of the propeller shaft with a part eligible for installation. The FAA is issuing this AD to address the unsafe condition on these products.