Airworthiness Directive 06-5547
one-timeAirworthiness Directives; Rolls-Royce Corporation (Formerly Allison Engine Company, Allison Gas Turbine Division, and Detroit Diesel Allison) 250-B and 250-C Series Turboprop and Turboshaft Engines
What this AD requires
The FAA is adopting a new airworthiness directive (AD) for Rolls-Royce Corporation 250-B and 250-C series turboprop and turboshaft engines with certain part numbers (P/Ns) of gas producer rotor assembly tie bolts manufactured by EXTEX Ltd., Pacific Sky Supply Inc., Rolls- Royce Corporation (RRC), and Superior Air Parts Inc. This AD requires operators to remove from service affected gas producer rotor assembly tie bolts, and install serviceable tie bolts. This AD results from eleven reports of RRC tie bolt failure due to high cycle fatigue. We are issuing this AD to prevent tie bolt failure that could cause loss of engine power, resulting in a first stage turbine wheel overspeed and an uncontained engine failure.
Which aircraft AD 06-5547 applies to
Applies only to engines with gas producer rotor assembly tie bolt part numbers listed in Table 1 installed (manufacturers: EXTEX, Rolls-Royce Corporation, Superior Air Parts, Pacific Sky Supply). Covers both 250-B turboprop and 250-C turboshaft variants.
Whether AD 06-5547 actually applies to your aircraft (by serial and installed parts) and whether it’s already complied with comes from that aircraft’s records.
How AD compliance is recorded
A valid compliance record (14 CFR 43.9) states:
Tailplate reads a tail number’s logbooks and matches every applicable AD — including this one — to its compliance evidence, with recurring next-due dates computed.
Look up a tail number →Read the full directive (Federal Register)Applicability is derived from the FAA directive corpus and is advisory, not a legal airworthiness determination. Compliance is established only from an aircraft’s actual records.