AD/B737/125 Amdt 3 - Centre Wing Fuel Tank Float Switch Wiring (Cth)

AIRWORTHINESS DIRECTIVE For the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/B737/125 Amdt 2 and issues the following 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.

Boeing 737 Series Aeroplanes AD/B737/125 Amdt 3 Centre Wing Fuel Tank Float Switch Wiring 4/2005

Applicability: Model 737-200, -200C, -300, -400 and -500 series aeroplanes, on which centre wing fuel tanks are activated.

Note 1: This Airworthiness Directive is not applicable to aeroplanes equipped with centre wing tank volumetric top-off systems or alternating current (AC) powered centre tank float switches. Requirement: 1. Accomplish either of the following on Model 737-200, -300, -400 and -500 series aeroplanes having line numbers 1 to 3108 inclusive:

a. Remove the fuelling float switch and wiring from the centre fuel tank and perform a detailed visual inspection of the float switch wiring, in accordance with Boeing Alert Service Bulletin (ASB) 737-28A1132 dated 2 December 1998 or Revision 1 dated 15 January 1999 or Revision 2 dated 17 June 1999, to detect discrepancies (i.e. evidence of electrical arcing; exposure of the copper conductor; presence or scent of fuel on the electrical wiring; or worn insulation). After the effective date of this Directive only Revision 2 may be used.