The authors studied the effects of marijuana intoxication on the ability
of 10 certified airplane pilots to operate a flight simulator. They used a
randomized double-blind crossover design to compare the effect of active
versus placebo marijuana. They found that all 10 pilots showed a
significant decrease in measurements of flying performance 30 minutes after
smoking active marijuana. For a group of 6 pilots tested sequentially for 6
hours, a nonsignificant decrease in flying performance continued for 2
hours after smoking the active drug. The authors conclude that the effects
of marijuana on flying performance may represent a sensitive indicator of
the drug's psychomotor effects.Abstract Teaser