COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES British Aerospace BAe 125 Series Aeroplanes AD/HS 125/73 Amdt 1 Fouling of Pipe Installations 5/98 Applicability: All model 125 Series 800 aeroplanes fitted with ventral tanks. Requirement: If not previously accomplished, inspect the area above the left hand upper forward corner of the ventral fuel tank for signs of fouling between fuel, oxygen and hydraulic pipes in accordance with British Aerospace 125 Series Service Bulletin 53-60 dated 8 November 1985. Note: CAA(UK) AD 006-11-85 refers. Compliance: The compliance remains unchanged as "Before further flight after 31 January 1986". This amendment becomes effective on 23 April 1998. Background: Fouling is possible between fuel, oxygen and hydraulic pipes which could lead to a hazardous condition developing. This directive has been reissued at amendment 1 following the return of a BAe 125 Series 800 aeroplane to the Australian register and effectively remains unchanged, containing some minor additions such as referencing the CAA(UK) airworthiness directive and identifying the service bulletin. The original issue of this airworthiness directive became effective on 31 January 1986.