Case-control study of risk factors for fatal and non-fatal injury in crashes of civil aircraft

BACKGROUND: There have been few studies of the risk factors for fatal injury in air crashes, and none of risk factors for all serious injury (fatal and non-fatal). OBJECTIVE: To identify the potentially modifiable risk factors for fatal and non-fatal injury in civil aircraft crashes in New Zealand. METHODS: We analyzed records from all reported civil aircraft crashes in New Zealand (1988-1994). Air crash data from the official databases were merged with nationwide injury records and information obtained from coroners' files. Pilots-in-command who were fatally injured were compared with pilots-in-command who were not fatally injured using 50 variables covering pilot, aircraft, environmental, and operational characteristics. A second analysis compared pilots-in-command who were seriously injured (either fatally or non-fatally) with those who were involved in a crash but not hospitalized with an injury. Univariate and multivariate logistic regression analyses were then conducted to estimate the odds associated with each of the factors identified by the above comparisons. RESULTS: The most significant risk factors for fatal and serious injury were aerobatic flight, post-crash fire, not having a certificate of airworthiness, and off-airport location. Environmental characteristics including terrain type, wind, rain, and elevation of the crash site were identified as risk factors, as was being under instruction. Flying a twin-engine aircraft was a risk factor for fatal injury, while piloting a microlight aircraft was a risk factor for all serious injury. CONCLUSION: Environmental and operational factors, rather than pilot or aircraft characteristics, are the key determinants of the injury outcome of civil aircraft crashes.