AD/A320/211 Stand-By Instruments Emergency Lighting (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.

Airbus Industrie A319, A320 and A321 Series Aeroplanes

AD/A320/211 Stand-By Instruments - Emergency Lighting 3/2008

Applicability:

A318, A319, A320 and A321 series aeroplanes, all serial numbers, fitted with classical standby instruments installed by Airbus modification 20011 or 21999 during production or by Airbus Service Bulletin (SB) A320-34-1280 whilst in service except:

a.     aircraft fitted with Integrated Standby Instrument System (ISIS) equipment installed by Airbus modification 27620 during production, or by Airbus SB A320-34-1261 or SB A320-34-1372 whilst in service, or

b.    aircraft having received Airbus modification 37329 or 37330 during production or by Airbus SB A320-33-1057 whilst in service.

Requirement:

Unless already accomplished, modify the electrical supply logic of the under glare shield flood lighting in accordance with the instructions in SB A320-33-1057 or later EASA approved revision.

Note:  EASA AD 2007-0286 refers.

Compliance:

No later than 27 May 2011.

This Airworthiness Directive becomes effective on 13 March 2008.

Background:

The European Aviation Safety Agency (EASA) has advised that some operators have reported occurrences of loss of the AC BUS 1 with subsequent loss of the AC ESS BUS and DC ESS BUS resulting in the loss of five upper Display Units and the loss of integral lighting.  In this situation flight crew have reported concerns in reading the standby instruments when the DOME lights were selected to OFF.

This situation, if not corrected, could increase the workload of the flight crew which constitutes an unsafe condition.

This Directive mandates the modification of the electrical supply logic by adding a back-up supply on the battery hot bus for the under glare shield flood lighting.

Charles Lenarcic
Delegate of the Civil Aviation Safety Authority

23 January 2008