Airworthiness Directive 80-26-51
one-timeAirworthiness Directives; HEADING: BOEING Model 737 Series Airplanes ACTION: SUMMARY: DATES: Effective December 13, 1980. ADDRESSES: FOR FURTHER INFORMATION
Which aircraft AD 80-26-51 applies to
Applies to Boeing Model 737 series airplanes, certificated in all categories, prior to line number 726 (control system jamming).
Whether AD 80-26-51 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.