Engine – Electronic Engine Control Software – Replacement
Superseded. Comply with 2020-0055, which replaces this document.
- Published
- Effective
- Deadline
AI-generated summary of the official EASA document. Verify against the PDF before acting.
What to do
Operators must update the EEC software on Group 1 engines within 60 days of the directive's effective date, 27 November 2018, following CFM International's service bulletin instructions. Installation or uploading of affected software on any engine is prohibited after the effective date. Alternative methods of compliance may be approved by EASA if properly substantiated.
Summary
EASA Airworthiness Directive 2018-0251 is an airworthiness directive addressing CFM International LEAP-1B engines installed on Boeing 737-8 and 737-9 aircraft. It mandates updating the electronic engine control (EEC) software to prevent potential thrust loss caused by water accumulation in the FADEC pressure subsystem. This directive applies to all serial numbers of LEAP-1B21 through LEAP-1B28BBJ2 engine models.
What changed
This directive introduces a requirement to replace affected EEC software versions with updated versions that improve fault detection related to pressure sensor discrepancies. It prohibits installation or uploading of affected software on engines and mandates compliance within 60 days for engines with affected software. The update is intended to mitigate the risk of thrust loss during takeoff due to water accumulation in pressure sensing lines.
Why it matters
This directive is critical for operators and maintenance organizations to ensure continued airworthiness and safe engine performance. Failure to comply could result in thrust loss and reduced aircraft control during critical phases of flight. Compliance ensures regulatory adherence and reduces the risk of in-flight engine control issues related to software faults.
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Get the next one by email
New ADs and bulletins for CFM International LEAP-1B, Boeing 737-8 and Boeing 737-9, summarized like this page, every Monday.