The 'connect air trip'

As high-speed rail (HSR) is moving toward becoming a reality in the US, an increasing amount of focus is being placed on the interaction between rail and commercial air services. Generally, most of the attention is centered on the range of distances where HSR has the potential to compete with existing air services for on-corridor trips. However, there is another type of trip that is influenced by the interaction of air and rail but is often overlooked by demand modelers: the ‘connect air trip’.

Within the context of HSR travel, we define a connect air trip as a trip that includes at least one rail leg and a connection to a commercial flight. As an example, imagine a passenger who travels via HSR from Greenville, SC to Atlanta, GA then connects to a flight to New York, NY.

Alternatives to connect air trips typically include the following: (1) air-only itineraries which have the same legs as the connect air trip (e.g. a flight from Greenville to Atlanta, then another flight from Atlanta to New York); (2) multi-leg air itineraries with a different connecting location (e.g. a flight from Greenville to Washington, DC, then another flight from Washington, DC to New York); and occasionally (3) nonstop flights (e.g. a nonstop flight from Greenville to New York).

A number of factors need to be favorable for this type of rail trip to occur. First, there must be a rail station at or very near a hub airport. If the rail service does not immediately serve the airport terminal, it is essential that it is very close by and that there is frequent, easy-to-use shuttle service between the rail station and the airport. Second, connect air trips will only occur if the rail leg is sufficiently short that the air-rail trip is competitive with the air-only trip in terms of travel time. Finally, it is much more likely that significant volumes of connect air trips will occur if there is integrated ticketing between the rail provider and the air carrier, enabling travelers to book air-rail trips with a single transaction.

Though there are many unknowns, such as the strategic responses of airlines to the introduction of HSR service, early indications — including forecasts for US service and on the ground experience in Europe — indicate that under the right conditions, connect air trips can constitute an important market for HSR service. As the first of the US HSR services open in the coming years, it will be interesting to gain more insight into the magnitude of this often overlooked market segment.