COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Boeing 747 Series Aeroplanes AD/B747/73 Stabiliser Limit Switch Assembly 11/89 Applicability: All model Boeing 747 series aeroplanes as listed in Boeing Service Bulletin 747-27- 2228 Revision 1 dated 26 October 1984. Requirement: Action in accordance with Boeing SB 747-27-2228 Revision 1 dated 26 October 1984. Note: FAA AD 89-15-02 refers. Compliance: Prior to 2 May 1991. Background: The FAA have advised that reports have been received that even though the stabilizer controls have been set within safe operating limits, air loading on the horizontal stabilizer can cause the take off warning alarm to sound at speeds approaching V1 during take off when trim is set at the end of the "green band". This condition, if not corrected could result in unnecessary rejected take offs, and the consequent high potential for aircraft incidents and accidents.