EASA AD 2021-0118
Engine Fuel and Control — Pressure Sub-System Units — Operational Check
Summary
EASA Airworthiness Directive 2021-0118 is an airworthiness directive addressing the operational check of pressure sub-system units in CFM International LEAP-1B engines installed on Boeing 737-8 and 737-9 aircraft. It targets specific pressure sub-system units with part number 2474M65P06 that may be affected by corrosion. The directive mandates inspections and possible replacement of affected parts to ensure engine thrust control reliability.
What Changed
This new airworthiness directive introduces a requirement for a one-time operational check of affected pressure sub-system units before the Operational Readiness Flight for certain engines, and repetitive maintenance message checks for others. It also specifies corrective actions including replacement of affected parts with serviceable units and defines groups of engines based on prior compliance and installation status.
Why It Matters
This directive is critical for aviation professionals because corrosion in pressure sub-system units can lead to loss of engine thrust control, posing a safety risk. Operators and maintenance organizations must comply to maintain aircraft airworthiness and avoid potential in-flight engine control issues. Compliance ensures continued safe operation of Boeing 737-8 and 737-9 aircraft equipped with LEAP-1B engines.
What To Do
Operators must perform an operational check of affected pressure sub-system units on Group 1 engines before the Operational Readiness Flight, and conduct pre-flight maintenance message checks on Group 2 engines from the effective date. If any maintenance messages indicating faults are found, the affected parts must be replaced with serviceable units before the next flight. The effective date for compliance is 30 April 2021.
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