Airworthiness Directive 77-21-05
one-timeAD 77-21-05 · 1977-01-01 · other
Airworthiness Directives; inspection required by paragraph (a) of this AD, flame tube bridge piece leg cracking is found, establish a repetitive inspection
Which aircraft AD 77-21-05 applies to
MakesInspection Required By Paragraph Of This Ad Flame Tube Bridge Piece Leg Cracking Is Found Establish A Repetitive Inspection Interval For All
Applies to all models of the make above.
Whether AD 77-21-05 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 77-21-05 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 →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.