AD/TPE 331/38 - Second Stage Turbine Wheel Assembly - CANCELLED

This document cancels a previous aviation safety rule affecting specific aircraft engines.

What it does: Cancels Airworthiness Directive (AD) TPE 331/38, which previously required owners and operators of AlliedSignal (Garrett/AiResearch) TPE 331 series turbine engines to inspect and replace second stage turbine wheel assemblies. The old rule required this maintenance to be done within 50 hours of flight time after June 1988, following the manufacturer's Service Bulletin No. A72-0577.

Who it affects: Aircraft operators, owners, and maintenance organisations responsible for aircraft powered by TPE 331 series engines (commonly used in regional airliners and agricultural aircraft).

Why it matters: As of 24 September 2009, the mandatory inspection and replacement requirement no longer applies. This removes a regulatory maintenance burden that had become obsolete, potentially saving operators time and money while safety is maintained through other means.