This study finds that alcohol and pilot age impair radio communication during simulated flight. Young (mean age 25 years) and older (mean age 42 years) pilots flew in a light aircraft simulator during alcohol and placebo conditions. In the alcohol condition, pilots drank alcohol and flew after reaching 0.04% BAC, after reaching 0.10% BAC, and then 2, 4, 8, 24, and 48 h after they stopped drinking at 0.10% BAC. They flew at the same times in the placebo condition. Alcohol and age impaired communication-based and overall flying performance during and immediately after drinking. Most important, alcohol and age cumulatively impaired performance, since older pilots were more impaired by alcohol. Notably, performance was as impaired 2 h after reaching 0.10% BAC as it was at 0.10% BAC. Moreover, overall performance was impaired for 8 h after reaching 0.10% BAC.