Airline hub


An airline hub or hub airport is an airport used by one or more airlines to concentrate passenger traffic and flight operations. Hubs serve as transfer points to help get passengers to their final destination. It is part of the hub-and-spoke system. An airline may operate flights from several non-hub cities to the hub airport, and passengers traveling between spoke cities connect through the hub. This paradigm creates economies of scale that allow an airline to serve city-pairs that could otherwise not be economically served non-stop. This system contrasts with the point-to-point model, in which there are no hubs and nonstop flights are instead offered between spoke cities. Hub airports also serve origin and destination traffic.

Operations

The hub-and-spoke system allows an airline to serve the same number of destinations with fewer routes, so fewer aircraft are needed. The system can also increase the passenger load factor and facilitate larger and more efficient aircraft. A flight from a hub to a spoke carries not just passengers originating at the hub, but also passengers originating at multiple spoke cities. Additional employees and facilities are needed at the hub to cater to connecting passengers. To serve spoke cities of varying populations and demand, an airline requires several aircraft types, and specific training and equipment are necessary for each type. In addition, airlines may experience capacity constraints as they expand at their hub airports.
For the passenger, the hub-and-spoke system offers one-stop air service to a wide array of destinations. The downside is having to make a connection, which increases travel time compared to a direct flight. Additionally, airlines can come to monopolise their hubs, allowing them to freely increase fares as passengers have no alternative. High domestic connectivity in the United States is achieved through airport location and hub dominance. The top 10 megahubs in the US are dominated by American Airlines, Delta Air Lines, and United Airlines, three of the four largest United States–based airlines.

Banking

Airlines may operate banks of flights at their hubs, in which several flights arrive and depart within short periods of time. The banks may be known as "peaks" of activity at the hubs and the non-banks as "valleys". Banking allows for short connection times for passengers. However, an airline must assemble many resources to cater to the influx of flights during a bank, and having several aircraft on the ground at the same time can lead to congestion and delays. In addition, banking could result in inefficient aircraft utilisation, with aircraft waiting at spoke cities for the next bank.
Instead, some airlines have debanked their hubs, introducing a "rolling hub" in which flight arrivals and departures are spread throughout the day. This phenomenon is also known as "depeaking". While costs may decrease, connection times are longer at a rolling hub. American Airlines was the first to depeak its hubs, trying to improve profitability following the September 11 attacks. It rebanked its hubs in 2015, however, feeling the gain in connecting passengers would outweigh the rise in costs.
For example, the hub of Qatar Airways in Doha Airport has 471 daily movements to 140 destinations by March 2020 with an average of 262 seats per movement; in three main waves: 05:00–09:00, 16:00–21:00 and 23:00–03:00, allowing around 30 million connecting passengers in 2019.

History

United States

Before the US airline industry was deregulated in 1978, most airlines operated under the point-to-point system. The Civil Aeronautics Board dictated which routes an airline could fly. At the same time, however, some airlines began to experiment with the hub-and-spoke system. Delta Air Lines was the first to implement such a system, providing service to remote spoke cities from its Atlanta hub. After deregulation, many airlines quickly established hub-and-spoke route networks of their own.
Airport2024 pax.AmericanDeltaUnitedSouthwest
Atlanta52,51098438,6608533,839
Dallas/Fort Worth42,39028,4511,4209840
Chicago–O'Hare38,6208,0481,29614,477777
Los Angeles37,8645,2386,3415,4813,312
Denver37,8401,2621,72615,58512,524
New York–JFK31,3043,2247,81700
Charlotte28,50819,857555453393
Las Vegas28,0242,1812,4982,03410,552
Orlando27,8392,1812,4982,03410,552
Miami26,45415,1741,791898736
Phoenix–Sky Harbor25,5738,4111,7031,4418,342
Seattle/Tacoma25,4289365,1281,2741,079
San Francisco25,1291,6531,94310,732984
Newark24,5531,03481414,2820
Houston–Intercontinental23,37796196313,093298
Boston21,2172,4564,3001,765932
Minneapolis/St. Paul18,01862710,567657859
Fort Lauderdale17,0509601,9921,1731,950
New York–LaGuardia16,7142,1373,7761,0241,627
Detroit16,0837129,050246516
Philadelphia15,0827,536834558680
Salt Lake City13,5296077,8385061,469
Baltimore13,1595327785029,331
Washington DC–Dulles13,0651133766,623164
San Diego12,7521,4971,5241,5433,991
Washington DC–Reagan12,7333,4631,2007321,855
Tampa12,0431,7902,0501,2132,992
Nashville12,0351,1021,1557626,326
Austin10,6641,9261,4441,1794,418
Chicago–Midway10,391015009,241

Middle East

In 1974, the governments of Bahrain, Oman, Qatar and the United Arab Emirates took control of Gulf Air from the British Overseas Airways Corporation. Gulf Air became the flag carrier of the four Middle Eastern nations. It linked Oman, Qatar and the UAE to its Bahrain hub, from which it offered flights to destinations throughout Europe and Asia. In the UAE, Gulf Air focused on Abu Dhabi rather than Dubai, contrary to the aspirations of UAE Prime Minister Mohammed bin Rashid Al Maktoum to transform the latter into a world-class metropolis. Sheikh Mohammed proceeded to establish a new airline based in Dubai, Emirates, which launched operations in 1985.
Elsewhere in the Middle East region, Qatar and Oman decided to create their own airlines as well. Qatar Airways and Oman Air were both founded in 1993, with hubs at Doha and Muscat respectively. As the new airlines grew, their home nations relied less on Gulf Air to provide air service. Qatar withdrew its share in Gulf Air in 2002. In 2003, the UAE formed another national airline, Etihad Airways, which is based in Abu Dhabi. The country exited Gulf Air in 2006, and Oman followed in 2007. Gulf Air therefore became fully owned by the government of Bahrain.
Emirates, Qatar Airways, Saudia and Etihad Airways have since established large hubs at their respective home airports. The hubs, which benefit from their proximity to large population centres, have become popular stopover points on trips between Europe and Asia, for example. Their rapid growth has impacted the development of traditional hubs, such as London-Heathrow, Paris-Charles de Gaulle, and New York-JFK.

Types of hubs

Cargo hubs and scissor hubs

A cargo hub is an airport that primarily is operated by a cargo airline that uses the hub-and-spoke system. In the United States, two of the largest cargo hub airports, FedEx's Memphis Superhub and UPS Louisville Worldport, are close to the mean center of the United States population. FedEx's airline, FedEx Express, established its Memphis hub in 1973, prior to the deregulation of the air cargo industry in the United States. The system has created an efficient delivery system for the airline. UPS Airlines has followed a similar pattern in Louisville. In Europe, ASL Airlines, Cargolux and DHL Aviation follow a similar strategy and operate their primary hubs at Liège, Luxembourg and Leipzig respectively.
Additionally, Ted Stevens International Airport in Anchorage, Alaska, is a frequent stop-over hub for many cargo airlines flying between Asia and North America. Most cargo airlines only stop in Anchorage for refueling and customs, but FedEx and UPS frequently use Anchorage to sort trans-pacific packages between regional hubs on each continent in addition to refueling and customs.
Passenger airlines that operate in a similar manner to the FedEx and UPS hubs are often regarded as scissor hubs, as many flights to one destination all land and deplane passengers simultaneously and, after a passenger transit period, repeat a similar process for departure to the final destination of each plane. In past, Air India operated a scissor hub at London's Heathrow Airport, where passengers from Delhi, Ahmedabad, and Mumbai could continue onto a flight to Newark. Until its grounding, Jet Airways operated a similar scissor hub at Amsterdam Airport Schiphol to transport passengers from Bangalore, Mumbai and Delhi to Toronto-Pearson and vice versa. At the peak of operations at their former scissor hub at Brussels prior to the 2016 shift to Schiphol, flights operated from Mumbai, Delhi, and Chennai and continued onward to Toronto, New York, and Newark after a near-simultaneous stopover in Brussels and vice versa. An international scissor hub could be used for third and fourth freedom flights or it could be used for fifth freedom flights, for which a precursor is a bilateral treaty between two country pairs.
WestJet used to utilize St. John's as a scissor hub during its summer schedule for flights inbound from Ottawa, Toronto, and Orlando and outbound to Dublin and London–Gatwick. Qantas similarly used to utilize Los Angeles International Airport as a scissor hub for flights inbound from Melbourne, Brisbane or Sydney, where passengers could connect onwards if traveling to New York–JFK.