Airport Activity Statistics of Certificated Air Carriers: Summary Tables presents summary data for all scheduled and nonscheduled service by large certificated U.S. air carriersincluding the volume of passenger, freight, and mail enplanements, and aircraft departures for each airport served during the 12 months ending December 31, 1999.

Large certificated air carriers hold Certificates of Public Convenience and Necessity issued by the U.S. Department of Transportation (DOT) authorizing the performance of air transportation. Large certificated air carriers operate aircraft with seating capacity of more than 60 seats or a maximum payload capacity of more than 18,000 pounds. Data for commuter, intrastate, and foreign-flag air carriers are not included in this publication.

Source of Data

The data in this publication are compiled from information reported to DOT by the large certificated air carriers on BTS Form 41, Schedules T-100 and T-3.

Presentation of Data

The data in this publication are presented in five tables. Tables 1 and 2 contain summary data by type of service for carrier groups and individual air carriers, and summary figures by area and state. Tables 3, 4, and 5 show activity in air carrier system operations at large, medium, and small air traffic hubs. Data are not broken out by domestic or international operations at airports; only U.S. system operations are shown.

Air Traffic Hubs

Air traffic hubs are designated as geographic areas based on the percentage of total passengers enplaned in that area. A hub may have more than one airport in it. This definition of hub should not be confused with the definition used by the airlines in describing their hub-and-spoke route structures.

Individual communities fall into four hub classifications as determined by each communitys percentage of the total enplaned revenue passengers in all services and all operations of U.S. certificated route carriers within the 50 states, the District of Columbia, and other U.S. areas. Classifications for 1999 are based on 610,628,716 total enplaned revenue passengers.

The percentage and number of enplaned passengers in the hub classifications for 12 months ending December 31, 1999 are:

Hub classification Percent of total enplaned passengers Number of enplaned passengers
Large (L) 1.00 or more 6,106,287 or more
Medium (M) 0.25 to 0.999 1,526,571 to 6,106,287
Small (S) 0.05 to 0.249 305,314 to 1,526,571
Nonhub (N) Less than 0.05 Less than 305,314

During 1999 there were 116 air traffic hubs, representing 17 percent of the 693 total air traffic hubs and nonhubs in the 50 states, the District of Columbia, and other U.S. areas. The dominance of hubs in air traffic patterns is demonstrated by the fact that 97 percent of all passenger enplanements were recorded at these hubs. The table below shows the number of hubs/nonhubs and the number and percentage of passenger enplanements at the hubs/nonhubs.

Hub classification Number of hubs/nonhubs Number of airports Passengers enplaned Passengers (percent)
Large  29  69 458,665,099  75.11
Medium  31  48 96,394,866  15.79
Small  56  73  38,644,557    6.33
Nonhub 577 604  16,924,194    2.77
TOTAL 693 794 610,628,716 100.00