MIAMI – Industry experts say Southwest Airlines’ (WN) point-to-point route network makes it more vulnerable to broad problems than other carriers.

According to Henry Harteveldt, president of the Atmosphere Research Group, flight delays produce cascading complications at each flight’s subsequent stops, and the airline had scheduled more flights than it could handle.

Southwest’s pilot union also said the complex technical system, which reassigns and reroutes pilots during such delays, forced the airline to reassign more than 70% of its pilots over the weekend.

The airline has conceded that the initial wave of cancellations threw its entire system into disarray by preventing planes and staff from being in the correct places at the appropriate times according to schedule. In short, according to union president Casey Murray, WN’s operating system became “subject to massive failures under the slightest pressure.”

The mounting staff and aircraft concerns meant other flights had to be canceled as well, ensuing what the union refers to as a “domino effect.” It seems the airline’s network management software and “IT support” are to blame for the delays; a years-long issue, according to Murray.

Last June, WN saw a similar wave of cancellations, which it eventually blamed on overly optimistic forecasts about how rapidly it could ramp up flights and recall pilots before the summer travel uptick. As WN COO Mike Van de Ven said in a staff video, despite “a very aggressive hiring plan…we are still not where we want to be with staffing.”

Photo: Luke Ayers/Airways

Vaccine Mandates: an Unrelated Spin

Some in the right seat against the vaccine mandates have used the airline’s weekend predicament as a talking point. However, alleging that federal vaccine mandates generated WN’s flight cancelations is imaginary at best. It did not.

The airline’s Pilots Association had already asserted on Saturday that its pilots were “not participating in any official or unofficial action.” Then, on Monday, the FAA tweeted, “To be clear: None of the information from Southwest, its pilots’ union, or the FAA indicates that this weekend’s cancellations were related to vaccine mandates.”

Furthermore, when asked how much the airline’s vaccine mandate fueled the flight cancellations, airline CEO Gary Kelly told CNBC, “Zero,” adding that the rate of employee absences over the weekend was “very normal.” Similarly, the carrier’s pilots’ union said that over the weekend, its pilots called in sick at a normal rate.

On Tuesday, WN and American Airlines (AA) announced they would not comply with a Texas governor’s order prohibiting private businesses from requiring coronavirus vaccines in the state, citing federal regulations.

Southwest’s flight delays dropped to 2% by Tuesday. As Kelly noted, “When you get behind, it just takes several days to catch up.” To avoid a repeat of the incident, the airline said it would reduce the number of flights it had scheduled for the fall and build up a reserve of personnel to function as a safety net in the event of an emergency.

At the time of writing, there’s still no evidence of a strike or sick-out by WN employees.

Featured image: Southwest Airlines Boeing 737-700 N226WN. Photo: Andrew Henderson/Airways. Article sources:,,,,