'Too Fat To Fly' Passenger Sues Southwest Airlines For 'Discriminatory Actions'

May 3, 2012— -- Kenlie Tiggeman, the overweight passenger who garnered national attention last May after she claimed a Southwest gate agent told her she was "too fat to fly," is now suing the airline.

Tiggeman, who lives in New Orleans and blogs about weight loss on her website, AllTheWeigh.com, filed an injunction against Southwest in district court on April 20, alleging that the Southwest agents "did not follow their company policy and chose to discriminate, humiliate and embarrass" her in front of "airport onlookers," and that the airline uses "discriminatory actions ... toward obese customers."

Southwest currently has a Customers of Size policy, which requires passengers to buy a second seat if they can't fit between the armrests. Southwest's seats measure 17 inches across.

Tiggeman said she is not seeking monetary damages from the airline and filed the injunction application pro se, without legal representation. She said she wants an industry standard to be put in place for flyers who have to buy a second seat, including rules so that it is no longer up to gate attendants to decide whether or not an obese passenger has to purchase a second seat.

"If you're telling me I have to buy two seats, you should tell me at the point of purchase, not the day I'm flying when I check in at the terminal," she said.

Tiggeman said she was horrified last May when a Southwest Airlines gate agent told her to buy a second seat.

"The gate agent came up to me and he asked me how much I weighed, what size clothes I wore," Tiggeman said. "He said that I was too fat to fly, that I would need an additional seat, and he was really sort of crass about the whole thing."

At the time, Tiggeman said she weighed between "240 and 300 pounds."

"There was no privacy," she continued. "He didn't know what the policy was. So he actually brought in a supervisor as well who didn't know."

After the incident, Tiggeman said a Southwest executive contacted her to apologize, refunded her ticket and offered her flight vouchers, which she accepted. But last November, Tiggeman said she was again told by a Southwest agent that she was too fat too fly.

In a statement to "Nightline," Southwest spokeswoman Brandy King said she was aware of Tiggeman's blog post describing the suit, but hadn't confirmed the filing with the airline's legal department.

"We realize that it's a sensitive conversation and we train our Employees to approach the situation as discreetly as possible," King said in the statement. "The ... best case scenario is for the Customer to notify us of any special needs ahead of time. If providing the additional seat does not result in our having to deny another Customer boarding, we will refund the ticket to the Customer at no charge, which happens more than 90 percent of the time."

Tiggeman's crusade is just a small part in what feels like a war that has erupted between the airlines and their passengers. Many charge for everything from onboard snacks, to blankets and pillows, to excess baggage and body weight. Just today, Spirit Airlines announced that passengers may have to pay up to $100 for a carry-on, meaning bags that have to go in the overhead compartment and are checked in at the gate. Bags that can fit under the seat are still free.

But if you weigh more, should you pay more? Peter Singer, a bio-ethics professor at Princeton University, raised this simple, but inflammatory question.

ABC News' Dan Przygoda contributed to this report.