AD/EMB-120/11 Amdt 2 Ahrs Power Interruption (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/EMB-120/11 Amdt 1 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.

Embraer EMB-120 (Brasilia) Series Aeroplanes

AD/EMB-120/11 Amdt 2 AHRS Power Interruption 2/2010

Applicability:

Brasilia EMB-120, EMB-120RT and EMB-120ER all aircraft through to serial number 120291 inclusive.

Requirement:

Action in accordance with Embraer Service Bulletin (SB) 120-024-0008 revision 3 or later approved revisions.

Note 1:  Compliance in accordance with the SB constitutes terminating action for the requirements of the CTA 94-03-01R1.

Note 2:  CTA (Brazil) AD 94-03-01R1 Amdt 39-738 refers.

Compliance:

By 19 February 2010, unless previously accomplished.

This Amendment becomes effective on 20 January 2010.

Background:

The CTA has received a report of erroneous heading information being displayed on both EHSIs following certain combinations of electrical system failures, which are not considered improbable.

The original issue of the Directive provided temporary procedures which ensured that heading information was available following these failures

Amendment 1 provided terminating action for the temporary procedures.

This amendment introduces the use of later revisions of the Embraer SB.

Mike Higgins
Delegate of the Civil Aviation Safety Authority

19 January 2010