DOT, FAA, airlines, and airports all affect the efficiency of national airspace  system operations. Flight Delays Have Declined since 2007, Largely because of Fewer Flights, but Some Airports Still Experience and Contribute Substantial Delays to the System

		Flight Delays Have Decreased across the National Airspace System since 2007

The percentage of delayed arrivals has decreased systemwide since 2007,  according to ASQP data. As shown in figure 2, in 2009, about 21 percent  of flights were delayed systemwide—that is, arrived at least 15 minutes  late at their destination or were canceled or diverted—representing a  decrease of 6 percentage points from 2007. In addition, these  delayed arrivals had average delay times of almost an hour or more. FAA measures delays within the air  traffic control system to assess its performance because an inefficient air  traffic control system contributes to higher levels of delayed flights. Actions Could Reduce Delays, but FAA Lacks Airport-Specific On-Time Performance Targets, Limiting Its Ability to Prioritize Actions and Demonstrate Benefits

		FAA’s Actions to Reduce Delays Are Generally Being Implemented at the Most Congested Airports, but Many Actions Face Implementation Challenges

FAA’s actions have the potential to reduce delays in the next 2 to 3 years  and are generally being implemented at airports that experience and  contribute substantial delays to the system, including the 7 airports that  are the source of a majority of the delays in the system (Newark,  LaGuardia, Atlanta, JFK, Philadelphia, Chicago O’Hare, and San  Francisco). FAA also assessed capacity and delay reduction benefits  for some air traffic management improvements. FAA’s Use of Average On- Time Performance Masks Variations in Airport Performance and Limits FAA’s Ability to Prioritize Its Actions to Reduce Delays

Although FAA’s target of 88 percent on-time arrival performance provides  a measure of the agency’s overall goal to provide efficient air traffic  control services, it masks the wide variation in airport performance,  making it difficult to understand how individual airport performance  relates to the overall target. For example, in fiscal year 2009, Newark had  an on-time arrival rate of only 72 percent, while St. Louis easily exceeded  the target with 95 percent on-time performance. For example,  reducing delays at the airports that currently impose approximately 80  percent of all departure delays within the air traffic control system could  not only have a measurable benefit at these airports, but could also  improve performance of the overall national airspace system. Moreover, although NextGen will keep delays at many  airports from getting worse than would be expected without NextGen,  FAA’s NextGen modeling indicates that even if all ongoing and planned  NextGen technologies are implemented, a few airports, such as Atlanta,  Washington Dulles, and possibly Philadelphia, may not be able to meet the  projected increases in demand, and if market forces do not dampen that  demand, additional actions may be required at these airports. However,  without airport-specific targets, FAA cannot determine what additional  actions might be required to achieve a targeted level of performance at  these airports. Appendix I: Objectives, Scope, and Methodology

In this report, we examined the extent to which (1) delays in the U.S.  national aviation system have changed since 2007 and the factors  contributing to these changes, and (2) actions by the Department of  Transportation (DOT) and the Federal Aviation Administration (FAA) are  expected to reduce delays in the next 2 to 3 years. To determine how delays have changed, we analyzed DOT and FAA data  on U.S. passenger airline flight delays by airport and for the entire aviation  system through 2009. We focused on these 34 OEP airports  because they serve major metropolitan areas located in the continental  United States and handled more than 70 percent of passengers in the  system in 2008; additionally, much of the current delays in air traffic can  be traced to inadequate capacity relative to demand at these airports,  according to FAA. In  addition to being implemented at the most delayed airports, many of these  actions are also available at other OEP airports across the national  airspace system.
Why GAO Did This Study

Flight delays have beset the U.S. national airspace system. In 2007, more than one-quarter of all flights either arrived late or were canceled across the system, according to the Department of Transportation (DOT). DOT and its operating agency, the Federal Aviation Administration (FAA), are making substantial investments in transforming to a new air traffic control system--the Next Generation Air Transportation System (NextGen)--a system that is expected to reduce delays over the next decade. This requested report explains the extent to which (1) flight delays in the U.S. national airspace system have changed since 2007 and the contributing factors to these changes, and (2) actions by DOT and FAA are expected to reduce delays in the next 2 to 3 years. We analyzed DOT and FAA data for FAA's Operational Evolution Partnership (OEP) airports because they are in major metropolitan areas, serving over 70 percent of passengers in the system. We reviewed agency documents and interviewed DOT, FAA, airport, and airline officials and aviation industry experts.

What GAO Found

Flight delays have declined since 2007, largely because fewer flights have been scheduled by airlines as a result of the economic downturn, but some airports still experience and contribute substantial delays to the system. The percentage of flights that were delayed--that is, arrived at least 15 minutes after their scheduled time or were canceled or diverted--decreased 6 percentage points from 2007 to 2009, according to DOT data. Even with this decrease in delays, during 2009, at least one in four U.S. passenger flights arrived late at 5 airports--Newark Liberty International (Newark), LaGuardia, John F. Kennedy (JFK), Atlanta Hartsfield International (Atlanta), and San Francisco International--and these late arrivals had an average delay time of almost an hour or more. In addition to these airports having the highest percentage of flights with delayed arrivals, these 5 airports, along with Chicago O'Hare International and Philadelphia International (Philadelphia), were also the source of most of the departure delays within FAA's air traffic control system. FAA measures delays within the air traffic control system to assess its performance because an inefficient air traffic control system contributes to higher levels of delayed flights. An FAA air traffic control tower or other facility may delay flights departing from or destined to an airport because of inclement weather or heavy traffic volume at that airport. In 2009, of the 34 OEP airports in GAO's analysis, about 80 percent of departure delays occurring at airports across the national airspace system were the result of conditions affecting air traffic at just these 7 airports. DOT's and FAA's actions--including near-term elements of NextGen and other air traffic management improvements--could help reduce delays over the next 2 to 3 years and are generally being implemented at the airports that contribute to the most delays in the system. However, the extent to which these actions will reduce delays at individual airports or contribute to the agency's overall target is unclear. FAA has an 88 percent on-time arrival performance target for the national airspace system to measure how its actions help to improve systemwide on-time performance. This target, however, masks the wide variation in airport performance. For example, in fiscal year 2009, Newark had an on-time arrival rate of 72 percent, while St. Louis International exceeded the target with 95 percent. FAA has not established airport-specific performance targets, making it difficult to assess whether FAA's actions will lead to the desired on-time performance at these airports or whether further actions are required to improve performance, especially at airports affecting delays systemwide. Also, FAA's modeling indicates that even if all ongoing and planned NextGen and other improvements are implemented, a few airports, such as Atlanta, Washington Dulles International, and Philadelphia, may not be able to meet the projected increases in demand, and if market forces do not dampen that demand, additional actions may be required at these airports. However, without airport-specific targets, FAA cannot determine what additional actions might be required to achieve a targeted level of performance at these airports.