Is AD 91-18-04 a recurring Airworthiness Directive?

No — AD 91-18-04 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 91-18-04 apply to?

AD 91-18-04 applies to Boeing — models 747. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 91-18-04

one-time

AD 91-18-04 · 1991-01-01 · airframe

Airworthiness Directives; 13, 1990, for evidence of cracking at the latest of the following times, as applicable. Repeat the inspections thereafter at inter

Which aircraft AD 91-18-04 applies to

MakesBoeing

Models747

Inspect for frame cracking per Boeing SB 747-53-2302 (dated December 13, 1990) at the latest of: 10,000 total airplane flight cycles, 10,000 cycles since frame replacement per that SB, or within 1,000 cycles after the effective date; repeat inspections at intervals not exceeding 2,000 flight cycles.

Whether AD 91-18-04 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 91-18-04 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.