Airworthiness Directive 2021-26-03
recurringAirworthiness Directives; The Boeing Company Airplanes
What this AD requires
The FAA is adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737-300, -400, and -500 series airplanes. This AD was prompted by an evaluation by the design approval holder (DAH) indicating that the frame splice between certain stringers is subject to widespread fatigue damage (WFD). This AD requires an inspection of certain fuselage frame splices for existing repairs, repetitive inspections of certain fuselage frame splices for cracking, and applicable on-condition actions. The FAA is issuing this AD to address the unsafe condition on these products.
Which aircraft AD 2021-26-03 applies to
Applicability as identified in Boeing Alert Requirements Bulletin 737-53A1388 RB, dated October 27, 2020. Installation of STC ST01219SE does not affect applicability; a change-in-product alternative method of compliance provision applies for airplanes with that STC installed.
Whether AD 2021-26-03 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 →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.