Airworthiness Directive 98-04-15
one-timeAirworthiness Directives; AlliedSignal Inc. TPE331 Series Turboprop and TSE331 Turboshaft Engines
What this AD requires
This amendment adopts a new airworthiness directive (AD), applicable to AlliedSignal Inc., (formerly Garrett Engine Division, Garrett Turbine Engine Company and AiResearch Manufacturing Company of Arizona) TPE331 series turboprop and TSE331 turboshaft engines, that requires replacement or radiographic inspection, and replacement, if necessary, of certain third stage turbine stators with serviceable parts. This amendment is prompted by a report of an outer band weld that cracked subsequent to a radiographic inspection required by a previous AD. The actions specified by this AD are intended to prevent third stage turbine wheel separation due to thermal fatigue cracking and shifting of the third stage turbine stator, which could contact the third stage turbine wheel and result in an uncontained engine failure and damage to the aircraft.
Which aircraft AD 98-04-15 applies to
Applies to engines (including the TSE331-3U turboshaft variant) with third stage turbine stators, P/N 868379-3, installed, except those engines with turbine stators listed by serial number in Table 1 of National Flight Services Alert Service Bulletin (ASB) No. NF-TPE331-A72-10961, dated April 28, 1997. Installed on but not limited to Mitsubishi MU-2B series, CASA C-212 series, Fairchild SA226 series (Swearingen Merlin/Metro), Prop-Jets Model 400, Twin Commander 680/690, Rockwell Commander S-2R, Shorts SC7 (Skyvan), Dornier 228 series, Beech 18/45 series and Models JRB-6/3N/3NM/3TM/B100, Pilatus PC-6 series, De Havilland DH104 series 7AXC (Dove), Ayres S-2R series, Grumman American G-164 series, Schweizer G-164 series airplanes, and Sikorsky S-55 series (Helitec S55T) helicopters.
Whether AD 98-04-15 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.