After more than 18 months of health risks, layoffs and disruptive passengers, some Republican lawmakers, including U.S. Rep. Jeff Van Drew, have said recent commercial flight chaos is purely a reaction to vaccine mandates by airlines.

In reality, the airline staffing shortage has been a festering situation ever since the pandemic halted flights in spring 2020.

“When an airline gets behind, it’s hard to catch up,” Southwest Airlines CEO Gary Kelly said on CNBC Tuesday. He said mass flight cancellations last weekend were not at all related to the airline planning to uphold a federal vaccine mandate for large companies.

The Southwest airline pilots' union also rejected such claims as fiction.

“There are false claims of job actions by Southwest Pilots currently gaining traction on social media and making their way into mainstream news. I can say with certainty that there are no work slowdowns or sickouts either related to the recent mandatory vaccine mandate or otherwise,” a written statement from Southwest Airline Pilots’ Association said on Sunday.

“SWAPA has not authorized, and will not condone, any job action.”

Still, Van Drew echoed his Republican colleague from Texas, U.S. Rep. Ted Cruz, in trying to link the recent flight turmoil solely to vaccination mandates.

“If these cancellations were caused by the Biden Administration forcing the hand of airlines to mandate that their employees get vaccinated, the American people should not have to bear the cost of cancelled flights,” Van Drew's statement said this week.

“If these vaccine mandates persist, we will continue to see the number of strikes rise, services will continually be harder to come by, and it's all because people are tired of the government interfering in their everyday lives," Van Drew said.

On Sunday, Cruz had suggested on Twitter that weekend flight cancellations were due to what he called the “illegal vaccine mandate.”

But overworked flight staff have been a problem for months as demand for domestic travel rebounded rather quickly over the summer.

“None of the information from Southwest, its pilots union, or the FAA indicates that this weekend’s cancellations were related to vaccine mandates,” the Federal Aviation Administration said in a statement issued Monday.

Southwest Airlines used an “emergency sick-call procedure” at least three times over the summer season, which required staff to verify an illness with a company doctor before calling out sick, as reported by The New York Times in August,

A federal lawsuit filed by the Southwest Airlines Pilots Association in late August detailed what it said were violations of labor laws dating back to the early days of the pandemic, when air travel plummeted.

Southwest implemented an "emergency time off" program, altered schedules, and scaled back prescription drug and retirement benefits all without collective bargaining, according to the suit as reported by Reuters.

A new lawsuit, specifically mentioning the vaccine mandate as another violation of collective bargaining, was filed on Friday.

A majority of Americans — 6 in 10 U.S. adults in a recent Gallup poll — generally approve of the federal mandate for COVID vaccinations for millions of U.S. workers.

Aside from stressful conditions outlined in the pilots' lawsuit, another likely factor is that flight attendants have reached a breaking point amid a workplace that has increasingly become hostile.

Back in June, Insider reported that flight attendants were considering quitting due to a rise in harassment and abuse on the job by passengers.

As of Aug. 23, the FAA had launched investigations into 693 on-flight disturbances in 2021, as reported by the New York Times. Before 2021, the agency investigated on average less than 150 incidents a year, according to an FAA spokesperson.

Since United Airlines began a mask requirement for all passengers, they have banned 700 people from returning to the airline, United Airlines CEO Scott Kirby told CBS News on Wednesday.

While there are very strong views on the vaccine issue, that was not behind last weekend’s flight cancellations and delays, Kelly repeated during his CNBC interview.

“I’ve never been in favor of any corporation imposing that kind of a mandate,” Kelly continued, “But by the executive order from President Biden… all major airlines have to have a vaccine mandate in place by Dec. 8.”

Kelly said his goal is not to fire anyone over refusal to be vaccinated, and he added workers could apply for exemptions based on medical or religious grounds, as has become an increasing strategy by those who do not want to be vaccinated.

American Airlines, Alaska Airlines and JetBlue also have announced a COVID-19 vaccine requirement for their respective employees, as they all are considered government contractors and part of the federal mandate announced by the president.

United Airlines previously met its own, self-imposed deadline for required vaccinations among employees.

Out of more than 67,000 staffers, 99.7% of the airline’s workforce now has been vaccinated, according to Kirby during his interview with CBS Mornings.

"I respect that you have a different opinion, but you now have a decision to make about whether you want to get vaccinated and stay at United or not," Kirby said of the mandate.

Following their deadline, 232 United workers who refused COVID vaccinations now were being terminated, Kirby said.

Another 2,000 United employees have applied for exemptions based on medical or religious grounds, and a federal judge today said that the airline cannot put those workers on unpaid leave, as their cases are processed, as reported by ABC New York.

United Airlines has announced a $1,000 bonus for all employees, as a thank you for their hard work during the public health crisis, Kirby confirmed on Wednesday.

The airline now is preparing for a rebound in international travel, announcing its biggest-ever expansion of transatlantic service — with flights from Newark Liberty International Airport starting in May and June.

The 10 Most Stolen Vehicles In New Jersey

Cozy winter getaway rentals in NJ

Fireplaces & hot tubs await, from the ski area of North Jersey, to peaceful, off-season lake time in South Jersey.

These house rentals have full amenities, for a relaxing and luxurious staycation.

Look inside The Avenue at American Dream

The American Dream mega mall in the Meadowlands is opening a deluxe boutique wing that promises to be a must-see experience, and not just for the luxury designer brands.

The best outdoor beer gardens at NJ breweries

There are more options than ever for enjoying a Garden State crafted beer in an outdoor setting.

New Jersey tied for first place (with Kentucky) with 43% growth in the craft beer scene from 2015 to 2019, according to C+R Research.

The following is a roundup of breweries around the state with scenic, dedicated outdoor seating as weather allows.

More From New Jersey 101.5 FM