This report was updated on 23 October 2014 with revised hours flown data used for the calculation of occurrence rates by aircraft type.


Why did we do this research

This study has been undertaken in order to further understanding of the nature and impact of fumes and smoke related occurrences in relation to the safety of aircraft operations in Australia and, in doing so, evaluate associated data availability and suitability. This report also addresses recommendations from a 2011 report commissioned by the Civil Aviation Safety Authority (CASA) by an Expert Panel on Aircraft Air Quality that aviation safety agencies work together to provide a comprehensive study of cabin air contamination incidents.

The study was undertaken in two parts; the first involved an in-depth analysis of aviation safety data sets held by the Australian Transport Safety Bureau (ATSB), CASA and the Department of Defence for the 2008-2012 period. The second part of the study involved a basic risk analysis of smoke/fumes safety events using the bowtie risk model.

What the research found

There were over 1,000 fumes/smoke events reported to both the ATSB and CASA over the 5-year period. From a flight safety perspective, most were found to be minor in consequence. There was a single flight crew incapacitation event and a further 11 minor injury events to crew. In the higher risk occurrences, precautionary defences (most commonly diversions) were found to be effective in avoiding escalation of the event.

The British Aerospace BAe 146 was the aircraft type most commonly involved in fumes/smoke events when taking into account flying activity. The Airbus A380, Boeing 767, Embraer EMB-120 and E-190 were among other aircraft types that also had a higher than average rate of fumes/smoke occurrences over the period.

The most common source of fumes/smoke was aircraft systems issues, primarily relating to failure or malfunction of electrical and auxiliary power unit (APU) systems. Equipment and furnishings also featured highly as a source of fumes and smoke. Within this category, air conditioning and galley equipment were the most common sources of fumes/smoke. External sources of fumes/smoke and cargo/baggage related events were relatively rare.

The matching of CASA and ATSB data records provided valuable information on the issue of fumes/smoke which enabled visibility of occurrences from both an engineering and operational perspective. However, many reports of fumes/smoke events contained insufficient detail for coding of the source or affected components.

Safety message

Fume and smoke events are generally appropriately managed by flight and cabin crew resulting in little consequence. Good reporting by aircraft operators, with sufficient detail, to both the ATSB and CASA where relevant will assist ongoing efforts to monitor the risk of fume and smoke events.


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