EASA AD CF-2020-41
Engine - Aircraft Flight Manual — Operating Limitations
Summary
The Airworthiness Directive CF-2020-41 titled 'Engine - Aircraft Flight Manual — Operating Limitations' applies to Airbus Canada Limited Partnership BD-500-1A10 and BD-500-1A11 aeroplanes equipped with Pratt & Whitney PW1521G, PW1524G, PW1521G-3, or PW1524G-3 engines. This directive addresses engine in-flight shutdowns by updating operating limitations in the Aircraft Flight Manual for operations above 29,000 feet and requires inspections following engine N1 speed exceedances. It mandates incorporation of an updated AFM supplement and inspections of the low-pressure compressor rotor when necessary.
What Changed
This directive supersedes AD CF-2019-37 and introduces an updated Aircraft Flight Manual supplement that includes new operating limitations and crew reporting procedures for engine N1 exceedances above 29,000 feet. It also recommends an optional modification involving a health management unit update to automatically detect and report N1 exceedances. Additionally, it requires borescope inspections of the first stage axial low-pressure compressor rotor when exceedances are reported or detected.
Why It Matters
This directive is critical for maintaining engine safety and preventing uncontained engine failures during high-altitude climbs at higher thrust settings. Operators and maintenance teams must comply to avoid potential in-flight shutdowns and ensure continued airworthiness. The updated procedures and inspections help identify engine damage early, reducing risk and improving reliability of affected aircraft.
What To Do
Operators must amend the approved Aircraft Flight Manual within 30 days of the effective date by incorporating the specified supplement and inform flight crews accordingly. When an N1 exceedance is reported by crew or automated systems, a borescope inspection of the low-pressure compressor rotor must be performed within 4 or 15 engine cycles depending on operation type. Incorporation of the optional health management unit update is recommended to enhance exceedance detection and reporting.
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.