Aviation safety issues and actions

Cabin Altitude Warning switc wiring diagram

Issue number: AO-2009-044-SI-01
Who it affects: Owners, operators and maintenance venues for Beech King Air 90 aircraft
Issue owner: Raytheon Aircraft Co
Transport function: Aviation: Maintenance
Background: Investigation Report AO-2009-044
Issue release date: 21 September 2011
Current issue status: Adequately addressed
Issue status justification:

Manufacturer had decided to change publication to reflect ATSB concerns.

Safety issue description

The cabin altitude warning pressure switch maintenance manual wiring diagram did not provide a clear indication of the wiring connections for the superseded switch.

Proactive Action

Action number: AO-2009-044-NSA-091
Action organisation: Raytheon Aircraft Co
Date: 21 September 2011
Action status: Closed
A technical Publications Change Request (PCR) has been submitted to change the Beechcraft Electrical Wiring Diagram Manual, P/N 90-590012-15, Cabin Pressurisation diagram covering LJ-919 to identify the cabin altitude warning switch poles NO and NC as follows

ATSB comment:

The ATSB is satisfied that the action by the aircraft manufacturer will, when included in the maintenance manual wiring diagram, adequately address the safety issue.
Last update 21 February 2014