Tightslot has it right but I do not drink beer on planes. On Long haul, glass of champagne before the push back, Gin and Tonic pre meal , 2nr glass of wine with meal, and Port with Cheese then sleep, and wake up in Far East / Africa or where ever. Have found that G&T has very restorative effect when tired / Jet lagged on long over night flights about 1 hour before touch down, but depends if on working trip or holiday. Short haul 1nr G&T pre meal on the way home. Have noticed that my favourite place for G&T is FL36, some how always tastes better there.