Southwest Airlines is still in damage-control mode after its passengers endured thousands of flight cancellations over the past weekend. Experts and other observers are also scratching their heads and trying to figure out what, exactly, caused the meltdown.

Officially, the company has blamed bad weather and a reduced number of air traffic controllers (although both of these issues affected many carriers, and only Southwest seemed to have massive disruptions). Right-wing politicians and commentators are pointing fingers at COVID vaccine mandates.

A union representing Southwest pilots said the problem was not related to anti-vax sentiment, and suggested a different culprit: An archaic technology system for reassigning pilots.

An analysis of Thinknum data, however, reveals yet another possibility — Southwest is chronically light on staff, relative to its market share. A likely outcome was that events on Friday catalyzed a chain reaction in the airline, whose margin of tolerance was already spread thin.

Here is a quick look at data which leads us to this possible conclusion.

To give a reference point against which some numbers may be benchmarked, Southwest is the second largest US airline by market share, according to the U.S. Department of Transportation.


According to LinkedIn headcount data tracked by Thinknum, Southwest has far fewer employees, relative to its market share, than other major airlines.

While its 18% national market share positions it as second in the US market, Southwest’s LinkedIn employee count with 28,581 staffers makes it the country’s fourth largest air carrier by workforce size. In contrast, American Airlines with a 19% market share (only one percentage point higher) has close to 100% more employees on LinkedIn with 57,052 workers. Southwest is an unequivocal outlier here since Delta and United with a respective market share of 15% and 12% have a similar LinkedIn-recorded labor force at 53,168 and 51,094 people.



The airline has also struggled to fill openings, relative to peers, as the industry rebounded over the past year. Southwest’s incoming CEO Bob Jordan has conceded that rallying people to the company’s ranks has been challenging since even before the pandemic started in early 2020, putting the brakes on travel throughout the country. While macroeconomic factors have played a role in stymying frontline hires across industries, they play only a minor role in Southwest’s staffing issues. 

Thinknum data shows that out of the 4 top U.S. airlines by market share, Southwest has been the slowest at growing its labor count. Over the past 6 months as the industry was taking off again with increased vaccination rates, the company acquired 1.6% more members. In the same time frame, Delta, American, and United added 4.9%, 4.2%, and 1.7% to their teams.

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