Airworthiness Directive 06-5929
one-timeAirworthiness Directives; Honeywell International Inc. TPE331 Series Turboprop, and TSE331-3U Model Turboshaft Engines
What this AD requires
The FAA is adopting a new airworthiness directive (AD) for certain Honeywell International Inc. TPE331 series turboprop, and TSE331-3U model turboshaft engines. This AD requires implementing a new flight cycle counting method for first, second, and third-stage turbine rotors used in aircraft that make multiple takeoffs and landings without an engine shutdown, and removing turbine rotors from service that have reached or exceeded their cycle life limits. This new flight cycle counting method requires determining total equivalent cycles accrued. This AD results from several reports of uncontained turbine rotor separation on engines used in special-use operations. We are issuing this AD to prevent uncontained failure of the turbine rotor due to low-cycle-fatigue (LCF), and damage to the aircraft.
Which aircraft AD 06-5929 applies to
TPE331 series are turboprop engines; TSE331-3U is a turboshaft engine variant (installed on Sikorsky S-55 series helicopters per the AD's aircraft table).
Whether AD 06-5929 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.