COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Boeing 747 Series Aeroplanes AD/B747/19 Lightning Protection of Fuel System - Modification 12/79 Applicability: All models. Document: 1. FAA AD 79-20-11, Amdt. 39-3583; or 2. Boeing SBs 747-28-2068 Rev. 3, 747-28-2069 Rev. 1 and 747-28-2084, Rev. 1. Compliance: Before 31 January 1981. Background: A review of the effects of lightning strikes to the B747 aeroplane over a 4-5 year period has prompted modifications to ensure a positive electrical path to ground to voltages that may occur due to a lightning strike to the aeroplane.