TRAVELUnited Airlines celebrates delivery of new Boeing 777-300ERThis image provided by United shows the carrier's first Boeing 777-300ER widebody jet.United Airlines/Tim StakeThe new Polaris business-class cabin as seen on United Airlines' first Boeing 777-300ER widebody jet.United AirlinesThe new Polaris business-class cabin as seen on United Airlines' first Boeing 777-300ER widebody jet.United AirlinesThe new Polaris business-class cabin as seen on United Airlines' first Boeing 777-300ER widebody jet.United Airlines