[The effects of small amounts of alcohol on in-flight activity]

Alcohol metabolism is described prior to an account of its effect on vigilance. The psychological and psychosomatic influence of alcohol is also illustrated in the light of experimental data indicating how it alters the response to stimuli. Alterations in various parameters following the administration of significantly small doses of alcohol were studied. Reaction time decreased, then increased, followed by a further decrease after about 1 1/2 hr. Even 1/8th litre depresses receptiveness of the reticular substance, and leads to lengthening of reaction times due to diminished ability to concentrate attention on a given task. CNS depression is also in proportion to the complexity of the performance required. This is particularly and dangerous in pilots, whose tasks are extremely precise and require close attention. Functional alterations induced by alcohol during flight may be numerous, due to disturbances connected with the specific conditions created by flying, and apparatuses whose physiological functions are susceptible to disturbance by flying itself. Alcohol, itself a harmful influence on piloting an aircraft, deteriorates these functions and conditions. Toxic substances present during flying and their potentiation by alcohol are considered. The effects of alcohol, added to these specific pathogenetic toxic effects, quickly and readily lead to a fall in overall psychophysical efficiency, and prejudice flight safety. the reason why a decrease in the limit intake doses to less than 2 cc/kg, equivalent to a blood value of 0.5 g 0/00, to ensure safe control of the plane, is desirable is explained.