Alcohol is a widely used drug, and its abuse is a serious public health problem. In aviation environment has special safety implications.It impairs almost all forms of cognitive function, such as information processing, decision-making, attention and reasoning. Visual and vestibular functions are also adversely affected. The performance of any demanding task, such as of course flying an aircraft, is thus impaired. Besides, many studies have shown a significant proportion of aircraft accidents associated with alcohol use. Alcohol increases the risk of spatial disorientation, hypoxia and poor +Gz tolerance. Here you can download an interesting report about this issue – from the aeromedical point of view – published by Australian Transportation Safety Bureau. There always seemed to me useful because of its briefness.
** Alcohol and Human Performance from Aviation Perspective: A review
David G. Newman / ATSB Australian Transportation Safety Bureau- 2004