Service Bulletin

SB 669

Lycoming Engines

Issued: 2026-06-30
Revision: -
Document type: SB
Models covered: 0

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SB 669

Lycoming Engines

Issued 2026-06-30

Manufacturer - not an FAA rule

NOT AN FAA REQUIREMENT — This is a manufacturer document. It is not an FAA Airworthiness Directive and compliance is not required by 14 CFR 39 unless an AD cites it.

Hartzell Engine Tech (HET) Exhaust Bypass Valve Assembly

Source: Lycoming Engines, retrieved 2026-09-01

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