AIRWORTHINESS DIRECTIVE On the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/DHC-8/98 and issues the following AD under subregulation 39.1 (1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section. Bombardier (Boeing Canada/De Havilland) DHC-8 Series Aeroplanes AD/DHC-8/98 Amdt 1 Engine Oil Coolers 8/2004 Applicability: Model DHC-8 aeroplanes on which engine oil coolers have been installed per LORI, Inc., Supplemental Type Certificate SA8937SW. Note 1: These oil coolers may be installed on but may not be limited to Model DHC- 8-101, -102, -103, -106, -201, -202, -301, -311, -314, and –315 aeroplanes. Requirement: 1. Carry out a review of aeroplane maintenance records, or a detailed inspection in accordance with the Accomplishment Instructions of Honeywell Service Bulletin 28E99-79-2036, dated September 23, 2002, to positively determine the part numbers (P/N) and serial numbers (S/N) of the engine oil coolers. If neither engine oil cooler has a S/N as listed in Table 1 of the service bulletin, no further action is required. 2a. If only one engine oil cooler has a S/N as listed in Table 1: remove the affected part and install a part that has been reworked per the service bulletin. 2b. If both engine oil coolers have S/Ns as listed in Table 1 of the service bulletin: remove the affected parts and install a part that has been reworked per the service bulletin. 3. Do not install an engine oil cooler having a S/N as listed in Table 1 of Honeywell Service Bulletin 28E99-79-2036, dated September 23, 2002. Note 2: FAA AD 2004-09-31 Amdt 39-13621 refers. Compliance: For Requirement 1: Unless previously accomplished, within 7 days after the effective date of this AD, For Requirement 2a: Unless previously accomplished, within 90 days after the effective date of this AD. For Requirement 2b: At least one of the oil coolers must be replaced before further flight with the second oil cooler to be replaced within 90 days from the effective date of this Directive. For Requirement 3: From the effective date of this Directive. Bombardier (Boeing Canada/De Havilland) DHC-8 Series Aeroplanes AD/DHC-8/98 Amdt 1 (continued) This Amendment becomes effective on 5 August 2004. Background: This action is necessary to prevent oil leakage from the engine oil coolers, consequent in-flight engine shutdown due to low oil pressure, and reduced controllability of the aeroplane. This action is intended to address the identified unsafe condition. This amendment changes the applicability of the Directive by removing reference to specific models, but retaining the reference to the Lori STC, which is the determining feature for action to take place. The original issue of this Directive became effective on 8 July 2004. James Coyne Delegate of the Civil Aviation Safety Authority 23 June 2004 The above AD is notified in the Commonwealth of Australia Gazette on 14 July 2004.