Aviation safety issues and actions

Required navigation performance approach procedure

Issue number: AO-2012-138-SI-01
Who it affects: Flight crew conducting RNP-AR operations
Issue owner: Qantas Airways Limited
Transport function: Aviation: Air transport
Background: Investigation Report AO-2012-138
Issue release date: 29 October 2014
Current issue status: Adequately addressed
Issue status justification:

The procedure has been modified to ensure the last-assigned altitude remains in the auto-flight system as a defence against a descent below this level.

Safety issue description

The company’s Required Navigation Performance approach procedure allowed the flight crew to set the approach minimum altitude in the auto-flight system prior to commencing the approach. This did not ensure the altitude alerting system reflected the assigned altitude limit of 7,000 ft and removed the defence of that alert when the flight crew did not identify the disengagement of the flight management computer-derived VNAV PTH mode.

Proactive Action

Action number: AO-2012-138-NSA-038
Action organisation: Qantas Airways Limited
Date: 29 October 2014
Action status: Closed

Qantas Airways Limited advised that the procedure that permitted the flight crew to set the approach minimum altitude on the Mode Control Panel (MCP) when cleared for the RNP-AR approach has been replaced. The new procedure requires that the flight crew retain the current altitude limit on the MCP until cleared for the approach and within approximately 2 NM (4 km) of the approach commencement, with the selection of the flight management computer-derived VNAV PTH indicated on the flight mode annunciator.

Last update 29 October 2014