Superseded. This AD was superseded by AD 2023-03-15. Verify which one applies to your serial and effectivity before any maintenance action.
AD 2021-07-09
Effective 05/12/2021 · Published 04/07/2021
Airworthiness Directives; The Boeing Company Airplanes
Summary
The FAA is superseding Airworthiness Directive (AD) 2007-07- 03, which applied to certain The Boeing Company Model 747-100, 747- 100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, 747SR, and 747SP series airplanes. AD 2007-07-03 required repetitive tests to detect hot air leaking from the trim air diffuser ducts or sidewall riser duct assemblies (collectively referred to as TADDs…