COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Gulfstream (Grumman) G1159 and G-IV Series Aeroplanes AIRWORTHINESS DIRECTIVE For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CAR 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. AD/G1159/39 Landing Gear Door Control Valves 7/2001 DM Applicability: Gulfstream Model G-1159, G-1159A, G-1159B, G-IV, and G-V series aeroplanes. Requirement: 1. Perform a visual inspection to determine if any landing gear door control valve having Gulfstream part number (P/N) 1159SCH231-33 with Eaton/Sterer P/N 65940-1, -1 Rev. A, or -1 Rev. B, is installed. No further action is required if there are no P/N 1159SCH231-33 with Eaton/Sterer P/N 65940-1, -1 Rev. A, or -1 Rev. B valves installed on the aircraft. 2. If during the inspection, any landing gear door control valve having P/N 1159SCH231-33 with Eaton/Sterer P/N 65940-1, -1 Rev. A, or -1 Rev. B is found: Replace the set screw with a new set screw, fill with Dow Corning RTV 732 sealant, and label the valve as P/N 65490-1 Rev. C; in accordance with; Gulfstream G-II Alert Customer Bulletin (ACB) No. 27 (for Model G-1159 and G- 1159A series aeroplanes); G-III ACB No. 13 (for model G-1159B series aeroplanes); G-IV ACB No. 27 (for Model G-IV series aeroplanes); and G-V ACB No.12 (for Model G-V series aeroplane); all dated 20 March 2001, as applicable. 3. Do not install a landing gear door control valve unless it (a) has been modified according to Requirement 2 or (b) is of P/N 1159CH231-33 with Eaton/Sterer P/N 65940-1, Rev. C. Note: FAA AD 2001-08-13 refers. COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Compliance: 1. Unless already accomplished, carry out the inspection within 15 landings or 30 days after the effective date of this Directive whichever occurs earlier. 2. (a) For valves having serial number 1900 or higher, within 5 landings or 15 days after the date of inspection (carried out in accordance with Requirement 1), whichever occurs earlier. (b) For valves having serial number less than 1900, within 50 landings or 90 days after the date of inspection (carried out in accordance with Requirement 1), whichever occurs earlier. 3. From the effective date of this Directive. This Airworthiness Directive becomes effective on 6 June 2001. Background: This Directive has been issued to prevent the loss of hydraulic system fluid due to failure of door control valve of landing gear. Eugene Paul Holzapfel Delegate of the Civil Aviation Safety Authority 28 May 2001 The above AD is notified in the Commonwealth of Australia Gazette on 6 June 2001.