According to the U.S. Department of Transportation's Bureau of Transportation Statistics, Sea-Tac Airport was best in on-time departures among major U.S. Airports between January 1, 2010 and June 30, 2010. According to the data, 89.06 percent of Sea-Tac flights departed on time in the first half of 2010. Sea-Tac Airport served more than fifteen million commercial airline passengers during this period.
Sea-Tac has benefited from the recent on-time performance of its largest carrier Alaska Airlines. In August 2010, Alaska ranked second amongst the nation's 18 largest airlines with an on-time departure rate of 88.7 percent in the U.S. Hawaiian Airlines, which also operates out of Sea-Tac, ranked number one with a 95.6 percent on-time departure rate. Continental Airlines came in third with an 87.1 percent U.S. on-time departure rate. Comair, JetBlue, and Delta had the worst scores with respective on-time departure rates of 76.4, 77.1, and 77.4 percent.
Behind Sea-Tac, Portland International Airport finished second with 88.87 percent of flights departing on-time. Portland is also a hub for Alaska Airlines and its sister carrier, Horizon Air. Sea-Tac and Portland both benefit from moderate climates with typically light snowfall totals and few thunderstorms.
On-time departure times have improved in recent years. The data from August 2010 shows that U.S. airlines had their second best August for on-time departures since 1995. Overall, 81.7 percent of commercial airline flights departed on-time for the month. Airline analysts cited lower traffic volumes and benign weather helped improve results.
Carriers also have the disincentive of a $27,500 fine per customer if a flight leaves three hours or more past its scheduled departure time. U.S. Transportation Secretary Ray LaHood imposed this rule on April 29, 2010. A flight delayed three or more hours with 150 passengers, would cost an airline $4,125,000 in fines. Only one flight was more than three hours late departing in August 2010. This compares to 66 flights that departed three or more hours late in August 2009.
New York's JFK, Miami International, and Chicago's Midway Airport had the worst on-time departure performances among major airports. Fewer than 74 percent of all flights departed on time from these airports in the first half of 2010.