Airworthiness Directive 2004-22-04
one-timeAirworthiness Directives; Boeing Model 747-400, -400D, and -400F Series Airplanes Equipped With General Electric (GE) or Pratt & Whitney (P&W) Series Engines
What this AD requires
This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 747-400, -400D, and -400F series airplanes, equipped with GE or P&W series engines. This amendment requires modifications and functional tests of the wiring of the wire integration unit and the air supply control test unit (ASCTU) of the engine bleed air distribution system. The actions specified by this AD are intended to prevent inadvertent commanded shutdown of the engine bleed air distribution systems due to an erroneous ASCTU command. This type of shutdown could cause depressurization of the airplane and subsequent ice build-up on the engine inlets during descent, which could result in ingestion of ice into the engine(s) and consequent loss of thrust on one or more engines. This action is intended to address the identified unsafe condition.
Which aircraft AD 2004-22-04 applies to
As listed in Boeing Service Bulletin 747-36A2136, Revision 2, dated May 13, 2004
Whether AD 2004-22-04 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:
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.