AD 98-04-15
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Honeywell International Inc. | TPE331-1 | Airworthiness Directives; AlliedSignal Inc. TPE331 Series Turboprop and TSE331 Turboshaft Engines |
| engine | Honeywell International Inc. | TPE331-2 | Airworthiness Directives; AlliedSignal Inc. TPE331 Series Turboprop and TSE331 Turboshaft Engines |
| engine | Honeywell International Inc. | TPE331-2UA | Airworthiness Directives; AlliedSignal Inc. TPE331 Series Turboprop and TSE331 Turboshaft Engines |
| engine | Honeywell International Inc. | TPE331-3U | Airworthiness Directives; AlliedSignal Inc. TPE331 Series Turboprop and TSE331 Turboshaft Engines |
| engine | Honeywell International Inc. | TPE331-3UW | Airworthiness Directives; AlliedSignal Inc. TPE331 Series Turboprop and TSE331 Turboshaft Engines |
| engine | Honeywell International Inc. | TPE331-5 | Airworthiness Directives; AlliedSignal Inc. TPE331 Series Turboprop and TSE331 Turboshaft Engines |
| engine | Honeywell International Inc. | TPE331-5A | Airworthiness Directives; AlliedSignal Inc. TPE331 Series Turboprop and TSE331 Turboshaft Engines |
| engine | Honeywell International Inc. | TPE331-5AB | Airworthiness Directives; AlliedSignal Inc. TPE331 Series Turboprop and TSE331 Turboshaft Engines |
| engine | Honeywell International Inc. | TPE331-5B | Airworthiness Directives; AlliedSignal Inc. TPE331 Series Turboprop and TSE331 Turboshaft Engines |
| engine | Honeywell International Inc. | TPE331-6 | Airworthiness Directives; AlliedSignal Inc. TPE331 Series Turboprop and TSE331 Turboshaft Engines |
Unsafe Condition
Third stage turbine wheel separation due to thermal fatigue cracking and shifting of the third stage turbine stator, which could result in an uncontained engine failure and damage to the aircraft.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Replace or radiographic inspect, and replace if necessary, third stage turbine stators with serviceable parts following the removal schedule based on cycles in service since prior inspection. Remove unserviceable stators per engine maintenance manuals.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 600 cycles in service (CIS) after the effective date of this AD, at next access, or prior to March 31, 2002, whichever occurs first (for certain conditions).
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
AlliedSignal Inc. TPE331-1, -2, -2UA, -3U, -3UW, -5, -5A, -5AB, -5B, -6, -6A turboprop and TSE331-3U turboshaft engines with third stage turbine stators, Part Number 868379-3, except those with serial numbers listed in National Flight Services ASB NF-TPE331-A72-10961 Table 1.
AI-generated summary from the source AD text. Verify against the official source before acting.
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.