Aviation safety issues and actions

Replacement of cabin altitude warning switch

Issue number: AO-2009-044-SI-02
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

Safety issue description

The aircraft maintenance manuals did not include the operating specifications of the replacement cabin altitude warning pressure switch hampering the required verification of switch serviceabilty.

Proactive Action

Action number: AO-2009-044-NSA-075
Action organisation: Raytheon Aircraft Co
Date: 21 September 2011
Action status: Closed
In response to this occurrence, aircraft manufacturer advised that: The 101-384028-47 switch is a replacement for the 101-384028-3 switch and has the same pressure parameters as the -3 switch; 10,500+000/-500 feet. The Electrical Wiring Diagram parts listing will contain the following at the next revision “Order 101-384028-47 for spares.”

ATSB comment:

The ATSB is satisfied that the action by the aircraft manufacturer will, when implemented, adequately address the safety issue.
Last update 21 February 2014