Aviation safety issues and actions

Required modifications for M18 aircraft under Supplemental Type Certificate SVA521

Issue number: AI-2011-150-SI-03
Who it affects: Aerial work industry
Issue owner: Rebel Ag
Transport function: Aviation: General aviation
Background: Investigation Report AI-2011-150
Issue release date: 09 April 2013
Current issue status: Adequately addressed
Issue status justification: Issue will no longer exist once safety action is completed.

Safety issue description

There was limited assurance that M18 and M18A Dromader aircraft incorporating Supplemental Type Certificate SVA521 would exhibit acceptable handling and performance characteristics if not fitted with vortex generators and M18B standard elevators, in particular that the risk of longitudinal instability had been reliably addressed.

Proactive Action

Action number: AI-2011-150-NSA-033
Action organisation: Rebel Ag
Date: 09 April 2013
Action status: Closed

The owner and developer of Supplemental Type Certificate (STC) SVA521 reported that pending Civil Aviation Safety Authority (CASA) approval, they were in the process of amending it to include the fitment of vortex generators and M18B standard elevators as prerequisites for applying the STC.


Proactive Action

Action number: AI-2011-150-NSA-035
Action organisation: Civil Aviation Safety Authority (CASA)
Date: 09 April 2013
Action status: Closed

CASA advised that it will ensure that the SVA521 Engineering Order and aircraft flight manual (AFM) supplement are amended to add M18B standard elevators and vortex generators as required modifications

ATSB comment:

The ATSB is satisfied that the proposed safety action will, when implemented, adequately address the safety issue.

Last update 08 January 2014