EASA AD 2017-0151R1: Engine — Exhaust System — Modification

What to do

Operators of affected GE Aviation Czech M601 and H-series engines must modify Group 1 engines during the next qualified engine shop visit or within specified compliance times based on engine manufacture date and service history. Installation of affected parts is prohibited after modification or from the effective date for Group 2 engines. Compliance must be ensured according to the schedules detailed in the AD and associated Alert Service Bulletins.

Summary

EASA Airworthiness Directive 2017-0151R1 is a regulatory document addressing modification requirements for the exhaust system of GE Aviation Czech M601, H75, H80, and H85 series engines. These engines are commonly installed on aircraft such as Thrush Aircraft Inc. S-2R, PZL-106 Kruk, Air Tractor AT-300/400/500 series, Allied Ag Cat G-164 series, RUAG Do 28, and Aircraft Industries L-410. The directive mandates modifications to prevent potential power turbine or quill shaft spline failures that could lead to engine overspeed and subsequent safety hazards.

What changed

EASA Airworthiness Directive 2017-0151R1 revises the original AD 2017-0151 by incorporating references to updated Engine Maintenance Manuals reflecting a TBO extension program completed by GE Aviation Czech. It updates the Alert Service Bulletin revision to Revision 03 and clarifies compliance requirements for affected engines. The revision ensures alignment with the latest maintenance and modification instructions.

Why it matters

This directive is critical for aviation professionals as it addresses a significant safety risk related to power turbine failures that could cause severe engine damage and jeopardize aircraft control. Operators and maintenance organizations must comply to maintain airworthiness and avoid unsafe conditions. The AD also affects maintenance planning due to updated compliance timelines and modification procedures.