Ad/ATR 42/19 Amdt 1 - Fuel Tank Safety Fuel Airworthiness Limitations (Cth)

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/ATR 42/19 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.

Avions de Transport Regional ATR 42 Series Aeroplanes

AD/ATR 42/19 Amdt 1 Fuel Tank Safety Fuel
Airworthiness Limitations 11/2007 DM

Applicability:	ATR 42-200, -300, -320, -400 and -500 series aeroplanes.
Requirement:	1.    Maintenance/Inspection Tasks -
a.     Fuel Airworthiness Limitations (FAL) identified in ‘Appendix A - Time Limits’ in the following ATR42 Maintenance Review Board Reports (MRBR) are to be completed at the time intervals and as specified in that document with the exception of the task “General Visual Inspection of centre wing box and inboard/outboard fuel tanks”:
(i)    For ATR 42-200, -300 and -320 aeroplanes - Revision 6 dated January 2004, and
(ii)   For ATR 42-400 and -500 aeroplanes - Revision 5 dated January 2004.
b.    Carry out the task “General Visual Inspection of centre wing box and inboard/outboard fuel tanks” - (CMR task reference 28.10.00, MPD task reference 281000-DVI-10000).
2.    Critical Design Control Configuration Limitations (CDCCL) - The operator shall ensure that their internal documentation is amended to reflect the data contained within the CDCCL section of the applicable MRBR and to provide appropriate text to highlight the existence of each CDCCL.  The operator’s internal procedures and documentation ensuring management of control of CDCCL shall be fully implemented.
Later Revisions of the above documents approved by the European Aviation Safety Agency (EASA) are acceptable for compliance with this requirement.
Note 1:  ATR All Operator Message AOM 42/72/2007/05 Issue 3 dated 6 September 2007 and ATR Service Letter ATR42-28-5004 dated 23 March 2007 contain additional information regarding the above requirements.
Note 2:  EASA AD 2006-0219R1 refers.
Compliance:	For Requirement 1.a. - Within three months after the effective date of the original issue of this Directive.

For Requirement 1.b. - Either:

(i)    Within twelve years since new (ie date of aircraft manufacture), or

(ii)   Within six years after the effective date of the original issue of this Directive, or

(iii)   Within 20 000 hours time in service after the effective date of the original issue of this Directive,

whichever occurs first.

For Requirement 2 - Before 27 December 2007.

This Amendment becomes effective on 21 September 2007.

Background:

Subsequent to accidents involving Fuel Tank System explosions in flight and on the ground, the United States Federal Aviation Administration (FAA) published Special Federal Aviation Regulation 88 (SFAR 88) in June 2001.  SFAR 88 required a safety review of the aircraft Fuel Tank System to determine that the design meets the requirements of FAR § 25.901 and § 25.981(a) and (b).

A similar regulation has been recommended by the European Joint Aviation Authorities (JAA) to the European National Aviation Authorities in JAA letter 04/00/02/07/03-L024 of 3 February 2003.  The review was requested to be mandated by European National Airworthiness Authorities using JAR § 25.901(c), § 25.1309.

In August 2005 the EASA published a policy statement on the process for developing instructions for maintenance and inspection of Fuel Tank System ignition source prevention (EASA D 2005/CPRO, that also included the EASA expectations with regard to compliance times of the corrective actions on the unsafe and the not unsafe part of the harmonised design review results.  On a global scale the Type Certificate (TC) holders committed themselves to the EASA published compliance dates (see the EASA policy statement).  The EASA policy statement was revised in March 2006 resetting the date of 31 December 2005 for the unsafe related actions to 1 July 2006.

FAL are items arising from a systems safety analysis that have been shown to have failure mode(s) associated with an ‘unsafe condition’ as defined in FAA Memo
2003-112-15 ‘SFAR 88 - Mandatory Action Decision Criteria’.  These are identified in Failure Conditions for which an unacceptable probability of ignition risk could exist if specific tasks and/or practices are not performed in accordance with the manufacturers’ requirements.

The original issue of this Directive mandated the Fuel System Airworthiness Limitations comprising maintenance/inspection tasks and critical design control configuration limitations for ATR 42 series aeroplanes, that resulted from the design reviews and the JAA recommendation and EASA policy statement mentioned above.

This Amendment continues that mandate but more closely aligns the compliance options to those of the EASA.  The Amendment also references a new issue of ATR AOM 42/72/2007/05 as providing more information on fuel tank safety.

The original issue of this Directive became effective on 27 September 2007.

Charles Lenarcic
Delegate of the Civil Aviation Safety Authority

12 September 2007