Airworthiness Directive 90-04-06 R1
one-timeAirworthiness Directives; AIRWORTHINESS DIRECTIVES FINAL RULES: 90-04-06 R1 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 89-ANE-
Which aircraft AD 90-04-06 R1 applies to
Applies only to four-cylinder Textron Lycoming piston engines (not the full Lycoming engine line) — confirm exact model/serial from the records
Whether AD 90-04-06 R1 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:
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 →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.