COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Boeing 747 Series Aeroplanes AD/B747/38 Amdt 4 Body Station 1241 Bulkhead Splice 6/95 Applicability: Boeing B747 aircraft Serial Number 1-675, 677- 678, 680-684, 686-689 in 18 groups as listed in Boeing Service Bulletin (SB) 747-53-2283, Revision 4. Requirement: Inspect, visually, by eddy current and ultrasonically, the body station (BS) 1241 splice strap and forging in accordance with Boeing SB 747-53-2283, Revision 4. Note: FAA AD 92-08-02 refers. Compliance: Inspect at the thresholds & intervals specified in Boeing SB 747-53-2283, Rev 4. The effective date of changes introduced by this Amendment is 25 May 1995. Background: Cracks have been found in the BS 1241 splice strap and forging, even on aircraft which have been modified to SB 747-53-2219 or the production equivalent. Undetected cracking could lead to loss of cabin pressure and structural failure. This Amendment references the latest FAA AD and Revision 4 of the actioning document, SB 747-53-2283, which requires additional inspections in response to the recommendations of the Ageing Fleet B747 Structures Working Group.