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Airworthiness Directive

AD 99-04-04 64 FR 6516 Active

Federal Aviation Administration · 14 CFR part 39

Requires removal of the Slick magneto from the engine and inspection of the impulse coupling pawl for wear.

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FR document
99-3039
Amendment
39-11028
Published
1999-02-10
Effective
1999-02-25
Models covered
1

Last live check: 2026-08-19

Printed from https://aircraftdirectives.com/ad/99-04-04 · AircraftDirectives restates official FAA and manufacturer records; the official sources named on this sheet control. Not an airworthiness determination.

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AD

99-04-04

FR doc 99-3039 · 64 FR 6516

AD 99-04-04Published 1999-02-10Effective 1999-02-25

FAA rule - 14 CFR 39

FAA rule. Compliance with an applicable AD is required under 14 CFR 39.7. Check its effective date, applicability, compliance times and current status.

Requires removal of the Slick magneto from the engine and inspection of the impulse coupling pawl for wear.

Full official abstract

This amendment adopts a new airworthiness directive (AD) that is applicable to Textron Lycoming IO-540 and O-540 engines equipped with Slick Aircraft Products magnetos. This action requires removal of the Slick magneto from the engine and inspection of the impulse coupling pawl for wear. This amendment is prompted by several service difficulty reports, two incidents, and an accident involving severely worn and failed impulse couplings. The actions specified in this AD are intended to prevent failure of the magneto impulse coupling, resulting in seizure of the engine.

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All Lycoming O-540 directives

View on Federal Register (opens in a new tab) View this AD in FAA DRS (opens in a new tab) Print AD packet (opens the full Federal Register document in a new tab)

Applies to 1 model in our index