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-8/19 Brake Pressure Line 7/92 Applicability: Model DHC-8 series 100 and 300 aircraft with S/No 3 through 321. Requirement: Action in accordance with the technical requirements of Transport Canada Airworthiness Directive CF-92-09. Note: de Havilland SB No 8-29-21 refers. Compliance: As specified in the requirement document with revised effective date 30 June 1992. Background: Loss of hydraulic fluid from a failed brake pressure line located downstream of the quantity limiting valve resulted in total loss of the No 1 system. Attempts to use the parking brake started depletion of the No 2 hydraulic system fluid which prevented use of any hydraulic system component.