Date of Award


Document Type

Independent Study

Degree Name

Doctor of Philosophy (PhD)




The present study investigated the influence of ethanol on aviation performance 10 hours after subjects finished drinking. The results of past studies concerning alcohol hangover effects are conflicting. Some studies have shown that alcohol hangovers affect complex cognitive performance, while other studies have not found effects.

One aim of the present study was to observe hangover effects after strong and medium doses of alcohol with an intervening night of sleep. Furthermore, previous research has found that use of ethanol increased variability in flying performance. This implies that hangover effects influence some pilots more than others. Therefore, this study also examined individual pilot characteristics that may modify the degree of hangover effects observed.

In the present study, subjects’ performances were measured on several indices of information processing and optometric functioning that are theorized to be related to flying ability. The three groups of subjects were administered: (1) a placebo, (2) alcohol until their blood alcohol levels (BAL) reached 0.05% BAL, or (3) alcohol until their blood alcohol reached 0.1% BAL. Subjects were given overnight accommodations after the target BAL was reached. At 9 a.m. the following morning, the subjects piloted a Frasca 241 flight simulator. Effects of alcohol hangover were found on two aspects of airplane pilot performance. There were significant differences on two flight performance measures: bank angle and rate of turn. These differences were seen only between the placebo group and the high dose group (3mg/kg; 0.1% BAL). There were no significant differences in performance between the placebo group and the moderate alcohol dose (0.05% BAL) group. The results of the present study support the notion that alcohol impairs performance at least 10 hours after reaching 0.10% BAL.