Alaska Airlines in May was the most punctual major U.S. airline, with an on-time arrival rate of 89.2 percent,

according to FlightStats. On average, North American airlines delivered 77.6 percent of their flights to the gate within 15 minutes of schedule. Among the eight largest U.S.-based carriers, excluding regional partners, Delta (84.2 percent), US Airways (82.8 percent), Virgin America (82.4 percent), JetBlue (79.1 percent) and American (78.5 percent) posted above-average on-time ratings. United (77.2 percent) and Southwest (73.8 percent) posted below-average ratings, according to FlightStats.