AD/NAV/4 - Fuel System Selector Valves (Cth)

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 39.001(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.

Navion Series Aeroplanes AD/NAV/4 Fuel System Selector Valves 9/2008

Applicability: Sierra Hotel Aero, Inc. Models Navion (L-17A), Navion A (L-17B), (L-17C), Navion B, Navion D, Navion E, Navion F, Navion G, and Navion H aeroplanes. Requirement: 1. Do a one-time inspection of the entire fuel system in accordance with Sierra Hotel Aero, Inc. Navion Service Bulletin (SB) No. 106A, dated 1 May 2007; or American Navion Society, Ltd. Field SB No. 1001, dated 30 April 2007.

2. Unless within the last 5 years the fuel selector valve has been replaced with one of the valves specified in Requirement 3 of this AD. Do inspection and functional tests of the fuel selector valves.

If using Sierra Hotel Aero, Inc. service information, an allowance may be made for a 1 inch of mercury reduction from the 24 inches of mercury standard for every 1000 feet of altitude over sea level testing conditions in accordance with Sierra Hotel Aero, Inc. Navion SB No. 106A, or American Navion Society, Ltd. Field SB No. 1001.

3. If there are any defects discovered during any of the inspections or tests detailed in Requirement 1 or 2 of this AD, perform any corrective actions required including replacing the fuel selector valve with one of the Part Numbers (P/N) listed below.