As Southwest Airlines tries to return to normal, some flight cancellations persist.

Southwest Airways canceled quite a few hundred flights on Monday as it worked to take care of the challenges that led it to strike far more than a quarter of its scheduled flights more than the weekend.

In excess of 1,800 Southwest flights were canceled on Saturday and Sunday, accounting for far more than 28 p.c of its weekend schedule, in accordance to FlightAware, a tracking services. By late afternoon on Monday, Southwest experienced canceled about 10 p.c of the flights scheduled for the working day, just about 360 flights. About a 3rd of its flights were being delayed 15 minutes or a lot more.

Southwest blamed the cancellations on several brings about, including challenges with the weather conditions and air website traffic control on Friday and an inability to get flight crews and planes to in which they had been essential.

Cancellations on Friday, mostly caused by extreme climate, prevented planes and crews from getting exactly where they needed to be on Saturday, a cascading dilemma that led to cancellations and delays all through the weekend and into Monday, the airline stated.

“We hope to restore our total agenda as soon as attainable,” Southwest explained in a assertion. “To each client that knowledgeable a cancellation or delay, Southwest gives our sincerest regret pertaining to disrupted vacation options.” The airline’s share rate fell much more than 4 per cent Monday.

The airline and the union that signifies its pilots took pains through the weekend and on Monday to say that the disruption was not induced by protests over the airline’s a short while ago declared vaccination mandate, denying an strategy, fueled by some early news stories, that had received traction on the net between conservatives and anti-vaccination activists. Conservative lawmakers pointed to Southwest’s cancellations as proof that vaccine specifications could damage the financial system.

“Joe Biden’s illegal vaccine mandate at get the job done!” Senator Ted Cruz, Republican of Texas, claimed Sunday night time on Twitter. “Suddenly, we’re brief on pilots & air visitors controllers.” Senator Ron Johnson, Republican of Wisconsin, echoed those opinions on Monday.

The Federal Aviation Administration acknowledged that flights ended up delayed or canceled on Friday simply because of severe temperature, navy education routines and a temporary staffing lack at 1 air visitors handle center, but claimed that the disruption lasted only a couple hrs.

“Some airways keep on to practical experience scheduling problems owing to aircraft and crews remaining out of position,” the company claimed in a assertion over the weekend.

Casey Murray, the president of the Southwest Airlines Pilots Association, dismissed the strategy that pilots had named in unwell to protest the company’s vaccine mandate, while the union has requested a courtroom to avert Southwest from implementing that need. Pilots identified as in sick at a normal fee this weekend, he mentioned.

Instead, Mr. Murray claimed, the widespread cancellations ended up caused by technological issues and problems with how pilots are reassigned and rerouted in the course of disruptions, a process complex by Southwest’s uniquely substantial, level-to-issue community. In a regular working day, about 10 per cent of pilots are reassigned from the flights they have been scheduled to function. That determine was 71 p.c on Saturday and 85 % on Sunday, in accordance to Mr. Murray.

“That is unsustainable,” he said. “The domino impact carries on, and what we see, due to some inside failures, is it is going on so numerous periods that they just cannot move everyone.”

The airline suffered a identical string of cancellations in June, which its incoming chief govt, Robert Jordan, just lately blamed partly on extremely rosy assumptions about how effortlessly the airline could meet surging summer months demand from customers immediately after the doldrums of the pandemic.

“I think we could have been considerably less optimistic about how rapidly we could get folks back again off of go away and educated and all that,” Mr. Jordan explained at a September convention hosted by Cowen, an financial commitment lender.

Thousands of workers volunteered for buyouts, early retirement or prolonged-expression depart through the pandemic. And the airline has experienced to provide on new staff to switch people departed personnel to meet the demand, Mr. Jordan added.

“I’ve been at the airline for 33 several years,” he explained. “Constraints have often been, can you get plane, can you get airports, amenities, gates? This is the first time where the constraint is workers.”

The union also claimed in a assertion on Sunday that its customers are barred by federal regulation from using a strike to solve a labor dispute without having exhausting other selections first.

Though the union, which states it does not oppose vaccination, denied that its customers were being contacting in sick to protest the mandate, it did check with a decide on Friday to prevent the airline from enacting the vaccine mandate and other procedures. The ask for is component of a broader lawsuit that predates the mandate and centers on the union’s assertion that Southwest has taken a amount of “unilateral actions” in violation of labor law.

Southwest isn’t by yourself in seeing pushback from staff above a vaccine mandate. Past 7 days, hundreds of American Airlines’ personnel and their supporters protested its new mandate exterior the company’s Fort Really worth headquarters, in accordance to The Dallas Early morning News.

But lots of others have voiced aid for these types of specifications. United Airlines, the very first big U.S. airline to impose a mandate, has explained just about all of its 67,000 workers ended up vaccinated, with the exception of about 2,000 who used for spiritual or clinical exemptions. United mentioned it predicted to have to hearth much less than 250 workforce for failing to comply. The airline’s executives experienced envisioned some blowback but have been surprised by the constructive response, noting that it experienced gained quite a few a lot more candidates for open up flight attendant positions than it made use of to just before the pandemic.

“I did not appreciate the intensity of aid for a vaccine mandate that existed, because you listen to that loud anti-vax voice a lot more than you hear the folks that want it,” United’s chief government, Scott Kirby, told The New York Times this month. “But there are a lot more of them. And they’re just as powerful.”

Delta Air Strains has not imposed a vaccination necessity, but it stated it would charge unvaccinated staff members $200 a lot more a month for wellbeing insurance policies.