Source: adapted from the Wall Street Journal and Flightstats. (JFK – New York, John F. Kennedy; LAX – Los Angeles; ORD – Chicago; ATL – Atlanta; MCO – Orlando). Direct flights only.
The growth and compounding of airport congestion has incited airlines to extend the scheduled duration of many of their flights in order for them to have a higher chance of remaining “on time”. Delays are not related with the airborne flight time per se but with ground operations at airport terminals (e.g. gate access, boarding time, takeoff queues, etc.).
For instance, while in 1996 American Airlines Flight 33 between New York and Los Angeles was scheduled to last 6 hours, in 2010 the same flight was scheduled to last 6 hours 36 minutes. Thus, in light of growing congestion, airlines are able to maintain partially their “on time” performance by lengthening the duration of their scheduled flights. This process is indicative of a growing space / time divergence since it takes more time to cover the same amount of space.
In 2019, schedule improved with the JFK-LAX flights scheduled to be 6 hours 15 minutes. While the performance appears to be still lower than in the mid 1990s, the recent trends of slightly lower scheduled flights times are indicative of a better performance of the American air transport system. This is a combination of better load factors, runway and gate improvements and a better management of the airspace.