Commercial aircraft involved in high altitude operations are generally pressurised to protect the occupants from the adverse effects of hypoxia, decompression illness and hypothermia. Failure of the pressurisation system is a potential threat to flight safety. The purpose of this study was to determine the prevalence and consequences of aircraft decompression events in Australian civil aviation. The aim was to document the prevalence, nature, type, degree and extent of decompression events in Australian civil aviation, as well as the consequences of such events, especially hypoxia and pressure-related medical effects. A search of all incidents and accidents on the ATSB database was made for pressurisation failure events between 1 January 1975 and 31 March 2006. A total of 517 pressurisation failure events were found (two accidents, eight serious incidents and 507 incidents). Only one pressurisation failure event was fatal (0.2 per cent of the total events). Hypoxia was reported in four of the events, and ear barotrauma was also reported in four events, due to the subsequent emergency descent. A total of 10 events involved death, hypoxia or minor injury. Mechanical factors were responsible for the majority of pressurisation system failures (73 per cent). The average rate of cabin pressure change was 1,700 feet per minute, and the average maximum cabin altitude reached was 10,978 feet. In general, the results of this study show that there is a high chance of surviving a pressurisation system failure, provided that the failure is recognised and the corresponding emergency procedures are carried out expeditiously. Aircrew should maintain a high level of vigilance with respect to the potential hazards of cabin pressurisation system failure.
|Type:||Research and Analysis Report|
|Author(s):||Dr David G. Newman|
|Publication date:||30 June 2006|
|ISBN:||1 921092 70 X|