Is AD 99-3039 a recurring Airworthiness Directive?

No — AD 99-3039 is a one-time directive. Verify it was complied with in the aircraft's records.

Airworthiness Directive 99-3039

Q: Which aircraft does AD 99-3039 apply to?

AD 99-3039 applies to Textron Lycoming — models O-540-B2B5, O-540-B2C5, O-540-E4B5, O-540-E4C5, O-540-G1A5, O-540-G2A5, IO-540-K1A5, IO-540-K1B5. Serial/part conditions may narrow it to specific aircraft.

one-time

AD 99-3039 · 1999-02-10 · reciprocating engine

Airworthiness Directives; Textron Lycoming Reciprocating Engines IO-540 and O-540 Engines Equipped With Slick Aircraft Products Magnetos

What this AD requires

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.

Which aircraft AD 99-3039 applies to

MakesTextron Lycoming

ModelsO-540-B2B5, O-540-B2C5, O-540-E4B5, O-540-E4C5, O-540-G1A5, O-540-G2A5, IO-540-K1A5, IO-540-K1B5, IO-540-K1G5, O-540, IO-540

Part-conditional — 6251, 6252, 6255, 6351, 6355.

Applies only to the listed O-540/IO-540 engines equipped with Slick Aircraft Products magneto model numbers 6251, 6252, 6255, 6351, or 6355.

Whether AD 99-3039 actually applies to your aircraft (by serial and installed parts) and whether it’s already complied with comes from that aircraft’s records.

How AD compliance is recorded

A valid compliance record (14 CFR 43.9) states:

Method of compliance — The specific action taken (inspected, replaced, modified) and to what revision.

Date — When the work was done.

Aircraft time — Total time in service / tach at compliance — how recurring next-due is computed.

Signature & certificate — The A&P/IA who returned it to service, with certificate number.

Is AD 99-3039 complied with on your aircraft?

Tailplate reads a tail number’s logbooks and matches every applicable AD — including this one — to its compliance evidence, with recurring next-due dates computed.

Look up a tail number →Read the full directive (Federal Register)

Applicability is derived from the FAA directive corpus and is advisory, not a legal airworthiness determination. Compliance is established only from an aircraft’s actual records.