Why do most U.S. cities with multiple airports try to concentrate airline operations at just one airport instead of spreading out the load?

Question

Many large metropoles around the world have multiple major airports with commercial airline service:

• London, famously, has six (EGLL, EGLC, EGKK, EGSS, EGGW, EGMC),¹ although the latter four are far enough away to seriously stretch the bounds of “serving London”.
• Paris has two (LFPG and LFPO).²
• Rome has two (LIRF and LIRA).
• Moscow (the one in Матушка Россия, not the one in Idaho³) has four (UUDD, UUEE, UUWW, UUBW).
• Istanbul has three (LTFM, LTFJ, LTBA [cargo-only]).
• Beijing has two (ZBAA and ZBAD).
• Shanghai has two (ZSPD and ZSSS).
• Bangkok has two (VTBS and VTBD).
• Seoul has two (RKSI and RKSS).
• Tokyo has two (RJAA and RJTT).

In some of these cases (London, Istanbul, Beijing, Seoul), a new airport(s) has been opened explicitly to relieve the crush that existed previously, and/or preexisting satellite airports have been extensively touted as destinations in an effort to take pressure off overloaded primaries; in many to most of these cases, the existence of multiple airports has allowed particular categories of service to be concentrated at particular airports (for instance, one airport handles long-distance international flights while another handles domestic and regional flights, or one airport handles traditional carriers while another handles low-cost carriers, or [in Istanbul’s case] one airport is dedicated to cargo flights).

U.S. cities, like their international compatriots, frequently have multiple major airports.⁴ Unlike their international compatriots, however, U.S. cities show a pronounced tendency to try as hard as possible to squeeze everything into One Big Airport, with airlines often being kicked out of their homes at preexisting downtown airports and forced over to the One Big Airport (often an hour’s drive or more from the city it claims to serve):

• New York has three major airports (KJFK, KLGA, KEWR);⁵ of these, KLGA, despite being the most centrally located, has been consistently discriminated against in favour of the Two Big Airports (KJFK and KEWR), being almost entirely barred to flights to or from destinations outside the eastern half of the United States, and completely barred to flights operated by non-North-American airlines.⁶
• Chicago has two major airports (KORD and KMDW);⁷ despite KMDW’s closer-to-downtown location, the vast majority of traffic goes through KORD, with only one airline having more than a token presence at KMDW (that one airline accounts for over 95 percent of all passengers using the airport).
• Dallas/Fort Worth has two major airports (KDFW and KDAL); almost all traffic (again except for essentially just one airline) uses KDFW, which is centrally located for neither city. In fact, for many years, airlines were barred by federal law from operating full-size flights to or from airports not located in Texas or a Texas-neighbouring state out of any Dallas/Fort Worth airport other than KDFW,⁸ in a deliberate attempt to force everyone to use KDFW; this nearly caused the end of airline operations at the much-more-Dallas-convenient KDAL (which was only saved following a lengthy court battle), did, in fact, spell the doom for what was then Fort Worth’s main airport (KGSW, which was used solely for airline training flights after 1969, closed entirely in 1974, and almost completely razed in the 1980s and 1990s), and prevented KFTW, very close to downtown Fort Worth, from ever becoming successful as a commercial airport.
• Kansas City has two major airports (KMCI and KMKC); nearly all airline traffic goes through the One Big Airport (KMCI), located far from the city, while the centrally-located KMKC sees only limited cargo service.

(Washington, with two major airports [KIAD and KDCA], is a rare exception, and, even here, they tried [albeit incompletely successfully] to shoehorn everyone into One Big Airport; KDCA, located almost directly across the Potomac from downtown Washington, sees approximately the same level of service as KIAD, despite the former being restricted [with only a few exceptions] to flights no longer than approximately 2000 kilometers [in an effort to force flights to use KIAD, located nearly 50 kilometers away from the city].)

Why do U.S. cities have so much of a tendency to try to shoehorn everyone and everything into One Big Airport (or, in giant New York’s case, Two Big Airports), rather than spreading out the load between multiple smaller airports?

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¹: Two others (EGKB and EGWU) are kept barred to airline service due to selfish NIMBYs.

²: A third, LFPB, was closed to commercial traffic in 1980 (no reason given, but I’m suspecting it’s the damn NIMBYs again).

³: Which is itself served by an airport!

⁴: Possibly even more frequently, given the quintessentially American love of aviation.

⁵: A fourth airport, KHPN, sees some airline service but is handicapped by draconian passenger-volume limits (NIMBYs again) that keep it far below its full potential, while a fifth, KTEB, is completely barred to commercial service via NIMBY-imposed weight limits.

⁶: In fact, when KJFK (known at the time as KIDL) opened, the European airlines that had, until then, been happily resident at KLGA were forcibly evicted to the new, far-away airport through the cancellation of their permits to operate from KLGA.

⁷: A third airport, KCGX, located right on the downtown waterfront, was forcibly closed by the mayor of Chicago in 2003 because he didn’t like it.

⁸: These restrictions were loosened considerably in 2006, and finally repealed entirely in 2014.

Answer 1

A successful airport needs five things to thrive:

1. Financially solvent airlines/aircraft operators
2. Paying customers or passengers
3. Federal government support
4. Local popular support
5. A strong local tax base

In the case of Dallas, this consolidation was necessary to get KDFW built. Before that, Dallas Love Field was considered Dallas’s main airport and Greater Southwest International Airport was Fort Worth’s main airport. But, it took a combined effort of Dallas, Fort Worth, the Mid-Cities, and their five associated counties to appropriate the land, as well as tax and municipal bond dollars necessary to fund the project. That is why it was negotiated to put KDFW in the central-most location to the cities in the metroplex.

It was also a requirement from Fort Worth (the smaller of the two main cities) that Love Field and Greater Southwest International Airport not pose a significant threat of competition to the joint KDFW airport. Greater Southwest was closed as an airport. And, Love Field was put under legal restrictions curtailing operating flights with destinations outside of states adjoining Texas. This law was called the Wright Amendment. Fort Worth was allowed to retain a much smaller airport called Meacham International Airport.

The primary reason for this consolidation was two fold. One of which being the vast geographic range of the DFW Metroplex area. An airport on one side of the Metroplex could not effectively service the other side of the Metroplex. Operating multiple large airports puts an undue financial burden on the FAA that subsidizes international and national airports in the US. Other Class D, E (to the surface) and G airports around the DFW metroplex get much less funding from the FAA or none at all. They draw the majority of their funding primarily from private, corporate, or local municipality sources.

The other side of the coin is that airlines are able to consolidate their resources at the consolidated airport. Airlines would not have to sacrifice servicing half of the metroplex in order to reap the benefits of servicing the other half. And, neither Love Field nor Greater Southwest had the room to grow. Like Midway, the runways for those two (and still for Love Field) are comparatively short. And, except for the North end of the runway, the entire Love Field airport is closely surrounded by long-standing residential neighborhoods. Just like Midway.

As far as Chicago, it has been many years since I lived there. But, as I recall, it bears the same geographical problem as DFW. O’Hare Was supposed to completely replace Midway Airport. If not for a few discount seeking airlines and corporate air operations, Midway would have dwindled down to a Class D airfield.

O’Hare’s location is the central most location for servicing an area as far East as Gary, IN and as far West as Rockford, IL. Both of these cities have their own airports. But, there is not enough traffic (passenger business) to support major airlines. And, there is not enough of a tax base to generate major funding. This leads the two respective airports to serve as feeders for the main O’Hare hub. Most people (from my memory) preferred to just drive into O’Hare from Gary and Rockford to catch their flights. You can’t force the airlines to lose money by servicing an airport that does not generate revenue. And, you can’t force the local population to buy airline tickets too expensive to be worth the convenience of not driving to a busier airport. Case in point, Rockford lost all passenger service for 2 or 3 years in the early 2000s.

Answer 2

Paris is a good example because it has multiple major train stations that work the way you describe: traffic is distributed between them more or less equally, with each of them serving a certain geographic region of France in a hub-and-spoke model just like airlines do. Which means that if you want to go from one region of France to another, you always have to take a train to Paris, then leave the train station to get into the city, take the métro / a regional train / a bus / a taxi to get to the other train station, then get onto the next train.

This is very annoying and it would be much simpler if there was only one train station and you could simply change trains there without also having to change stations.

The same applies to flights. Everybody who has ever arrived at JFK and had to catch a connecting flight at LaGuardia during rush hour can attest to that.

Answer 3

As far as Kansas City’s situation, MCI was built to basically replace MKC. Larger airliners had simply outgrown the old airport. They needed space for runway safety areas and there was no room to expand in the middle of the city. Also the approaches are tight at MKC with high bluffs and tall buildings just to the southeast of the airport. According to Wikipedia, in 1963 the FAA called the downtown airport "one of the poorest major airports in the country for large jet aircraft" and recommended not to spend any more federal money on it. A 1965 runway overrun by a 707 may have been the final nail in the coffin for MKC as the primary airport. MCI was built out in the country where there was more land available for expansion.

Another consideration for downtown airports is noise. An airport being located closer to a city center may make for easier access, but it’s a nightmare for noise ordinances. And if MKC were still the main airport I can’t imagine what kind of mess adding all the MCI traffic to downtown would create.

There was an idea floated a few years ago about building a rival airport on the Kansas side, but it never got past the rumor stage. The discussions in Missouri about the new terminal at KMCI were getting messy and the Kansas governor mentioned the possibility, but gave no details. Johnson County, Kansas already has two Class D airports, KOJC and KIXD, but neither handles any scheduled airline traffic. OJC has been hemmed in by housing so it is not suitable for expansion. IXD has enough room, but I have a hard time imagining Johnson County residents being OK with all the increased noise of airline traffic.

Answer 4

I will only speak for the USA.(but we do have the majority of the worlds busiest airports) Most airports in the US are operated on behalf of local cities. The political structure of our city level governments produces poor long term planning. For multiple Airports to work as a unit you need a direct rapid and reliable transit between the local airports without the encumbrance of the travel security circus. Such a transit cannot rely on public streets, thus it requires the use of land and while many want to use the service few are willing to tolerate it near their own land. In addition flight is still seen as a service for the wealthy and is no longer viewed as travel of the future, so they do not pull large numbers of voters, thus airports are under much pressure for budget and local land use restrictions. I do not know of any new airports being constructed in many years, even where there is apparent need, just expanding runways for safety takes years of political fighting. All of which combines to prevent the needed connections.

There is federal grant money for airports but it comes with so many strings attached that the airports who accept the money can hardly be operated as proper businesses for decades after and beside that the money is narrowly directed on airport and could not be used to connect separated airports. However most airports must accept the money with all the strings because it is the only way to pay for every increasing government requirements such as remodeling terminals for TSA screening. (while loosing massive business revenue because of the same checkpoints)

And so, domestic hub and spoke airlines have been in decline and point to point have been on the rise for a couple of decades. This can increase use of many second tier airports without the need to connect them. There are no more domestic passenger 747 or A380 operating in the USA because of this, most hub based airlines and airports are used for connecting with international flights.