How is air traffic performance affected by type and location of markets? Is there any pattern to how air traffic performs with respect to the size and structure of markets, type of networks, and size of aircraft? In this paper, an empirical framework has been developed to examine the determinants of air traffic performance. Air traffic performance is defined as the ratio of airborne time to total rampto- ramp time. Using quarterly segment traffic data (i.e., T100 segment of Form 41) for the period 1995-2006, an econometric model is constructed to estimate and evaluate performance measures defined over market segments and networks. This econometric framework establishes and evaluates empirical linkages between performance measures and size of the markets, locations, distance, seasons of the year, and aircraft type over time. Statistical estimates indicate that size of market, type of aircraft, industry structure, and distance play important roles in influencing performance measures.