EASA AD US-2018-20-23
Engine - High Pressure Compressor Rotor Stage 2-5 Spools - Removal / Replacement
Summary
The Federal Aviation Administration's Airworthiness Directive 2018-20-23 addresses General Electric Company GE90-110B1 and GE90-115B turbofan engines equipped with certain high-pressure compressor (HPC) rotor stage 2-5 spools. This directive mandates the removal and replacement of specific HPC rotor stage 2-5 spools to prevent unsafe conditions. It applies to engines installed on aircraft operating in the United States.
What Changed
AD 2018-20-23 supersedes AD 2017-07-04 by reducing the life limits of affected HPC rotor stage 2-5 spools and expanding the applicability to include additional spools that were previously omitted. The new directive requires removal of these spools before reaching the revised life limits and prohibits installation of certain spools identified in earlier service bulletins.
Why It Matters
This AD is critical for aviation professionals because it addresses an unsafe condition that could affect engine reliability and safety. Operators and maintenance organizations must comply to avoid potential engine failures and ensure continued airworthiness. The directive also clarifies installation prohibitions to prevent reintroduction of unsafe parts.
What To Do
Affected operators must remove the specified HPC rotor stage 2-5 spools from service before reaching the new reduced life limits and replace them with eligible parts. Installation of certain HPC rotor stage 2-5 spools identified in previous GE service bulletins is prohibited. Compliance with this AD is mandatory by November 30, 2018.
Your fleet's weekly compliance brief
AI-summarized regulatory changes, compliance deadlines, and action items — filtered to your aircraft, every Monday.
AI-generated summary from official EASA source document. Always verify against the original.