AD/B747/391 Refuel Valve Control Unit (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.

Boeing 747 Series Aeroplanes

AD/B747/391 Refuel Valve Control Unit 5/2009

Applicability:

Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, 747SR, and 747SP series aeroplanes, as identified in Boeing Alert Service Bulletin 747-28A2291 Revision 1, dated
12 March 2009.

Requirement:

1.    Modify the refuel valve control unit for the reserve fuel tanks, by accomplishing all of the applicable actions specified in the Accomplishment Instructions of Boeing Alert Service Bulletin 747-28A2291 Revision 1.

2.    Revise the approved maintenance program by incorporating the information specified in Requirement 2(a) or 2(b) of this AD, as applicable.

(a)   For Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C,
747-200F, 747-300, 747SR, and 747SP series aeroplanes: Incorporate AWL No. 28-AWL-20 of Section D of the Boeing 747-100/200/300/SP Airworthiness Limitations (AWLs) and Certification Maintenance Requirements (CMRs), D6-13747-CMR, Revision January 2007, into the approved maintenance program.

(b)   For Model 747-400, 747-400D, and 747-400F series aeroplanes: Incorporate AWL No. 28-AWL-25 of Subsection D of the Boeing 747-400 Maintenance Planning Data (MPD) Document, D621U400-9, Section 9, Revision 24, dated June 2006, into the approved maintenance program.

Accomplishing the revision in accordance with a later revision of the MPD is an acceptable method of compliance if the revision is approved by the Manager, Seattle Aircraft Certification Office (ACO) of the United States Federal Aviation Administration (FAA).

3.    No alternative CDCCLs may be used unless the CDCCLs are approved as an AMOC.

Terminating Action for Maintenance Program Revision

(a)   For Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C,
747-200F, 747-300, 747SR, and 747SP series aeroplanes: Incorporating AWL No. 28-AWL-20 into the FAA-approved maintenance program in accordance with Requirement 1(a) of AD/B747/379, terminates the action required by Requirement 2(a) of this AD.

(b)   For Model 747-400, 747-400D, and 747-400F series aeroplanes: Incorporating AWL No. 28-AWL-25 into the approved maintenance program in accordance with Requirement 1(c) of AD/B747/378 terminates the action required by Requirement 2(b) of this AD.

Note:  FAA AD 2008-18-09 Amdt 39-15666 dated 25 August 2008 refers.

Compliance:

For Requirement 1 - Before 17 October 2013, unless previously accomplished.

For Requirement 2 - Concurrently with accomplishing the modification required by Requirement 1 of this AD.

For Requirement 3 - After accomplishing the applicable action specified in Requirement 2 of this AD.

This Airworthiness Directive becomes effective on 7 May 2009.

Background:

This AD results from fuel system reviews conducted by the manufacturer.  The issuing of this AD is to prevent lightning-induced electrical energy from entering a reserve fuel tank through the refuel valve, which could result in a fuel tank explosion and consequent loss of the aeroplane.

James Coyne
Delegate of the Civil Aviation Safety Authority

26 March 2009