Airworthiness Directives; Rolls-Royce Deutschland Ltd & Co KG (RRD) Dart 528, 529, 532, 535, 542, and 552 Series Turboprop Engines

The FAA is superseding an existing airworthiness directive (AD) for RRD Dart 528, 529, 532, 535, 542, and 552 Series turboprop engines. That AD currently requires a dimensional inspection of the intermediate pressure turbine (IPT) disk or an ultrasonic inspection of the seal arm contact between the high pressure turbine (HPT) and the IPT disk seal arm and reworking or replacing the IPT disk if worn beyond acceptable limits. This AD continues to require those actions. This AD results from us including an incorrect engine model and omitting an engine model from the applicability of the existing AD. We are issuing this AD to prevent HPT disk failure, which can result in an uncontained engine failure and damage to the airplane.