AD NUMBER: 2004-20-16
MANUFACTURER: Boeing
SUBJECT: Airworthiness Directive 2004-20-16
SUMMARY: This amendment adopts a new airworthiness
directive (AD), applicable to certain Boeing Model 747-200B, -200C,
-200F, -300, -400, -400D, and -400F series airplanes; and Model
747SP series airplanes, that requires repetitive functional tests
of the auxiliary power unit (APU) and engine fire shutoff switches
and repetitive replacements of the APU and engine fire shutoff
switches.