Airworthiness Directives; Rolls-Royce plc RB211-Trent 800 Series Turbofan Engines
This supplemental NPRM revises an earlier proposed airworthiness directive (AD) for the products listed above. This proposed AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:
Airworthiness Directives; Bombardier-Rotax GmbH Type 912 F, 912 S, and 914 F Series Reciprocating Engines
The FAA is superseding an existing airworthiness directive (AD) for certain serial numbers (S/Ns) of Bombardier-Rotax GmbH type 912 F and 914 F series reciprocating engines. That AD currently requires initial and repetitive visual inspections of the engine crankcase for cracks. This AD requires those same inspections, adds the 912 S series to the affected population, adds a test procedure to determine the engine suitability for a special flight permit, and changes applicability from engine S/N to crankcase S/N. This AD results from an increase in the affected crankcase population. We are issuing this AD to prevent oil loss caused by cracks in the engine crankcase, which could lead to in-flight failure of the engine and forced landing.