Document ID: chunk:federal_register_of_legislation:F2008L01245:body:0:p2
Version: federal_register_of_legislation:F2008L01245
Segment Type: other
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Character Range: 4207–5421

the monitoring function, including the system reconfiguration management, and leading to a runaway of nose wheel steering.

             AD/A320/27 (Direction Générale de l'Aviation Civile of France Airworthiness Directive F-1992-117-025(B) Revision 1), mandated the BSCU upgrade in order to improve the steering logic, but this modification has shown not to be sufficient to address the identified failure mechanism.

             A software modification is now implemented in BSCU standard 10 which improves the system reconfiguration management when this failure mechanism is detected.  BSCU standard 10 also includes other improvements as detailed in the associated Service Bulletin.

             This Directive mandates the modification or replacement of the BSCU standard 7, 9 or 9.1 by the BSCU standard 10.  SB A320-32-1336 notes at paragraph 1.A.(2).(a) that BSCU standard 10 is not compatible with Dunlop 46x16-20 tyres P/N 11659 T and 11661 T therefore this Directive also requires that these tyres be removed when BSCU standard 10 is installed and prohibits the fitment of these tyres to aircraft with BCSU standard 10.

David Punshon
Delegate of the Civil Aviation Safety Authority

6 March 2008