Hubs are exciting for many reasons, not least because of so many aircraft movements all happening at the same time. In 2019, 15 million people transited with Delta and its partners over Detroit – its second-largest hub. But where did they go?

~15 million people transited Detroit

In 2019, approximately 15 million Delta passengers (and those with SkyTeam partners) connected over Detroit. This means that just over half of Delta's passenger traffic (~55%) transited the hub. Around eight in ten passengers connected to another domestic service, examining booking data obtained via OAG Traffic Analyzer suggests.

While this level was entirely expected, just over one million people connected between North America and both Western Europe and Northeast Asia. They were distantly followed by the next largest market: North America to Central America with over 300,000.

Detroit Delta
Around 12 million Delta passengers connected to another US airport. Photo: Getty Images

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The largest international country markets

On a country basis, the main international markets were as follows. All involved connecting over Detroit from another US airport. The largest international-international country pair was Canada to China, with fewer than 20,000 passengers.

  1. USA-Canada
  2. USA-China
  3. USA-Mexico
  4. USA-Japan
  5. USA-Germany
  6. USA-Netherlands
  7. USA-United Kingdom
  8. USA-France
  9. USA-South Korea
  10. USA-Italy

Boston to Shanghai was the largest international origin-and-destination (O&D), with this routing just 6% longer than a non-stop would be. This is very little for a long-haul market, nicely illustrating Detroit's geographic position to capture traffic bound for Northeast Asia from particular parts of the US. Indeed, Delta's short-lived B747-400 fleet played an important role from Detroit, including to Shanghai.

Delta Air Lines Airbus A330neo
Photo: Vincenzo Pace | Simple Flying

Los Angeles to La Guardia was the largest

On an airport-pair basis, Los Angeles to New York La Guardia was the largest O&D. This was helped by La Guardia's perimeter rule, limiting flights to within 1,500 miles. As there are only two exceptions to this rule, this was (and remains) a relatively large indirect market.

It is despite JFK to Los Angeles, the USA's number-one O&D in 2019 by both passengers and revenue, according to the Department of Transportation data. We previously looked at American's B767-200ERs that plied the airwaves between the two airports.

Delta's top domestic O&Ds over Detroit
For clarity, this map only includes the largest domestic O&Ds. There are 22 in all, meaning three of the top-25 were international. These were: Boston-Shanghai (in seventh); Orlando-Nagoya (12th); and Boston-Beijing (20th). Image: GCMap.

Top-25 O&Ds over Detroit

Other interesting things are apparent with the 25 largest markets, shown below the photo. These include number-four, Columbus to Milwaukee, which is a distance of 330 miles non-stop. Short-lived Skybus, which existed between 2007 and 2008, operated it using its 156-seat A319s.

Delta Air Lines Boeing 737
Photo: Getty Images.
  1. Los Angeles over Detroit to La Guardia
  2. Boston-Madison
  3. Boston-Grand Rapids
  4. Colombus-Milwaukee
  5. Washington National-Madison
  6. Washington National-Seattle
  7. Boston-Shanghai Pudong
  8. Hartford-Las Vegas
  9. Grand Rapids-Seattle
  10. Baltimore-Seattle
  11. Hartford-Seattle
  12. Orlando-Nagoya
  13. Cleveland-Seattle
  14. Buffalo-Los Angeles
  15. Norfolk-San Diego
  16. Washington National-Las Vegas
  17. Grand Rapids-Las Vegas
  18. Grand Rapids-Orlando
  19. Baltimore-Los Angeles
  20. Boston-Beijing
  21. Cincinnati-Milwaukee
  22. Baltimore-Madison
  23. Washington National-Los Angeles
  24. Hartford-San Francisco
  25. Baltimore-Las Vegas

Norfolk to San Diego, which ranked 15th, was one of the USA's largest (virtually) unserved markets in 2019. Mainly driven by Navy demand, it had around 138,000 round-trip passengers across all airlines. Southwest launched it non-stop on a 'proper' basis in June 2021 after its once-weekly trial back in 2019 saw a seat load factor of 95%.

Have you transited Detroit with Delta? If yes, how did you find the experience? Let us know in the comments.