COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Bombardier (Boeing Canada/De Havilland) DHC-8 Series Aeroplanes AD/DHC-8/31 Firewall Electrical Terminal Block 4/94 DM Applicability: DHC-8 aircraft, models 102, 103, 106, 301, 311 and 314, serial numbers 003 through 362 inclusive. Requirement: Incorporate de Havilland Modification 8/1984 in accordance with Bombardier Regional Aircraft Division de Havilland Dash 8 Service Bulletin S.B.8-24-47 Revision A dated 29 November 1993. Note: Transport Canada AD CF-93-31 dated 17 December 1993 refers. Compliance: Prior to 23 April 1994. Background: Results from a de Havilland investigation show that the use of aluminium washers in the DC firewall terminal block and battery shunt cable assemblies can cause corrosion at the electrical connections. This can result in either a loose connection or generate a high electrical resistance at the connection point. Compliance with this Directive is designed to prevent the corrosion occurring. Compliance required by Transport Canada is extended by 30 days.