Emergence of Regional Jets and the Implications on Air Traffic Management

Airlines are increasingly using regional jets to better match aircraft size to high value, but limited demand markets. This has been especially important following increased financial pressure on the industry after September 11 2001. The increase in regional jets represents a significant change from traditional air traffic patterns. To investigate the possible impacts of this change, this study analyzed the emerging flight patterns and performance of regional jets compared to traditional jets and turboprops. In addition, a comparison between regional jet flight patterns in the United States and Europe was conducted. Regional jet operations generally cluster in the regions with high traditional jet operation density, implying a high level of interaction between the two aircraft types. The regional jets were observed to fly shorter routes than traditional jets, with few transcontinental flights. However, the gap between regional and narrow body traditional jet stage lengths appears to be closing. In addition, regional jets were observed to exhibit lower climb rates than traditional jets, which may impact air traffic control handling and sector design. It was also observed that regional jets cruise at lower altitudes than traditional jets possibly due to their shorter flight routes. Finally, it was observed that regional jets cruise at a lower Mach number than traditional jets, except on specific high density routes where the regional jets are either slowing down the traditional jet traffic or flying above their optimum cruise speed. Since the composition and utilization of the national fleet is changing, this will pose potential problems for air traffic management. In particular, it may cause serious congestion issues when demand increases during an economic recovery. Introduction One of the significant emerging changes to the national air space system is the number of regional jets, which has been increasing at an exponential rate. The rapid emergence of regional jets can be seen in Figure 1, which shows FAA registration data plotted between the third quarter of 1993 and the third quarter of 2002, for some of the regional jets commonly flown in the United States. The figure shows that the growth in regional jets is exponential, with CRJ2 and E145 registration data increasing the fastest. 0 100 200 300 400 500 600 700 800 90