EASA AD 2018-0239
Engine — High Pressure Turbine Case — Replacement
Summary
EASA Airworthiness Directive 2018-0239 is an official safety directive addressing the replacement of high pressure turbine (HPT) cases in CFM International LEAP-1B engines, which are installed on Boeing 737-8 and 737-9 aircraft. The directive targets specific HPT cases and combustor diffuser nozzle (CDN) cases identified by part and serial numbers due to concerns over unapproved weld repairs and potential life limit reductions. It mandates inspections and replacement of affected parts to prevent possible engine failure and uncontained debris release.
What Changed
This new directive introduces mandatory inspections and replacement requirements for certain HPT and CDN cases in LEAP-1B engines. It prohibits the installation of affected HPT cases on any engine from the effective date and allows installation of only serviceable CDN cases. The directive also provides criteria for identifying affected parts and outlines corrective actions if cracks are found during inspections.
Why It Matters
This directive is critical for aviation professionals because it addresses a safety risk that could lead to engine failure and uncontained debris, potentially compromising aircraft control. Operators and maintenance organizations must ensure compliance to maintain airworthiness and avoid operational disruptions. Compliance teams need to track affected parts and ensure inspections and replacements are completed within specified limits to meet regulatory requirements.
What To Do
Affected stakeholders must inspect all identified HPT cases before exceeding specified cycles to removal or upon first exposure to piece part level after the effective date, and replace any affected parts with serviceable ones. If cracks are found during inspection, the associated CDN case must also be replaced before the next flight or engine release to service. From 21 November 2018, installation of affected HPT cases is prohibited, and only serviceable CDN cases may be installed.
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