COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Fokker F28 Series Aeroplanes AD/F28/80 Amdt 1 Frame Station 10790 Coupling Fitting Bolts 13/97 Applicability: F28-1000 to -4000 Series, Serial Numbers 11003 to 11201, 11991 and 11992 with SB F28/53-125 installed. Requirement: Action in accordance with the Instructions for Part 1 of Fokker F28 SB F28/53-143. Note: Netherlands AD 1996-119(A) refers. Compliance: Within 3000 flight cycles after 2 January 1996 or before 1 February 1998, whichever occurs first. This Amendment becomes effective on 4 December 1997. Background: A new coupling was introduced at SB F28/53-125 to replace the original 7079-T6 coupling which was subject to stress corrosion and consequent SIP inspection. It has been discovered that the torque values specified in SB F28/53-125 are below what is actually required. This directive is issued to ensure that the coupling bolts are torqued to the value specified in the requirement document. This amendment corrects a misleading statement in the background, which referred to a steel coupling. The replacement coupling is made of 7075-T73. The compliance date has also been corrected. The original issue of this Airworthiness Directive became effective on 2 January 1996.