MIAMI (CBSMiami) – As air travel starts to pick up once again, airlines are seeing more reports of unruly passengers.

The incidents are often related to the federal transportation mask mandate.

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It’s gotten to a point where flight attendants are fine-tuning their self-defense skills to protect themselves, and they are working on those skills at a class specifically designed for them in Sunrise.

Flight attendants are training to hit, elbow, and gouge simulated aggressive passengers with actual passengers getting more violent than ever.

“You are going to possibly die. You need to defend yourself at all costs,” an undercover federal air marshal said during the class.

Undercover federal air marshals are guiding eight flight attendants through this self-defense course, the first class of its kind offered by the TSA since training was paused by the pandemic.

“It’s sad that it needs to happen,” said flight attendant Carrie, who just returned to her airline following a leave of absence.

Carrie admits she’s scared at times.

“Sometimes, a little bit,” she said. “You get on a plane full of people and some of them are not very happy and you just never know what’s going to happen.”

A brawl breaking out on a Frontier Airlines flight is among the latest unruly passenger incidents that the FAA says are skyrocketing.

Federal documents detail how passengers have berated, grabbed and struck flight attendants thousands of times since the start of a zero-tolerance policy earlier this year.

In May, a passenger punched a Southwest Airlines flight attendant, causing her to lose two of her teeth, according to her union.

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“There’s no backup at 30,000 feet,” said Noel Curtin, the assistant supervisor of air marshal in charge at the TSA Miami Field Office. “That plane is in the air. It has a crew that has to deal with the issues. It’s incumbent on us to make sure they are fully equipped.”

Federal officials say some passengers are fueled by alcohol but most are acting out over the federal transportation mask mandate, which make up three quarters of all incidents reported just this year.

“It’s so bad out there,” said Sara Nelson, the international president of the Association of Flight Attendants-CWA.

Nelson said airlines should pay their people to take these classes and the federal government should require that flight crews attend each year.

“We can have that muscle memory and be able to respond when someone is immediately attacking us,” Nelson said.

Instructors are teaching techniques that could be lifesaving, like pinning an attacker who is armed with a knife.

But the TSA says only a few hundred people have enrolled in this course after it reopened training in late June.

Veteran flight attendant Donna O’Neill says more like her should take this class to deal with a type of passenger becoming too common.

“I don’t ever want to use any of this” O’Neill said. “But if I had to I certainly feel much more confident.”

According to the Federal Aviation Administration, there’s been more than 3,600 unruly passenger reports.

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Of those, 2,600 were mask-related.

Lauren Pastrana