Australian and German studies of fumes/smoke events found that, from a flight safety perspective, most were minor in consequence.
The Australian Transport Safety Bureau (ATSB) studied over 1,000 fumes/smoke events reported to both the ATSB and CASA over the 5-year period of 2008-2012. At the same time, the German Federal Bureau of Aircraft Accident Investigation (BFU) studied 663 events that were reported to the agency in the 7-year period 2006-2012.
Both studies concluded that fume and smoke incidents are usually appropriately managed by flight and cabin crew and generally result in minor safety consequences. Also, both studies recommended that reporting needs to be improved.
German study: clear indications of effects on occupational health
The German study included research on the health consequences to aircraft occupants. There are indications of health impairments in terms of occupational health for pilots and cabin crew. In 10 of all fume events reported to the BFU (1.5%), the reporting person reported long-term health impairments at a later date.
- An improved identification and avoidance actions of cabin air contamination possibly hazardous to health.
- Improvement of the reporting procedure
- Improvement of the demonstration of compliance of cabin air quality during the certification process of transport aircraft
- Assessment of a possible conjunction between long-term health impairments and fume events by a qualified institution.
While most were minor in consequences, 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 Embraer EMB-120 Brasilia, Fokker 100, and Bombardier DHC-8-100/200 series aircraft 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 ATSB and CASA will continue to conduct quarterly trend monitoring of safety incident reporting for all types of incidents, including fumes and smoke.