The incident happened on a flight from Dallas to Greensboro, N.C., according to the airline. The flight was operated by American Airlines partner Envoy Air.
The incident happened when the flight attendant tried to help the dog’s owner with an air sickness bag, the Dallas Morning News reported. The dog allegedly lunged at the flight attendant and bit him.
The flight attendant received medical attention in Greensboro and was cleared to fly back to Dallas, where he received five stitches for the injury, the airline said.
The airline did not name the breed of dog involved. It also did not indicate what happened with the passenger.
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It’s legal for air passengers to travel with animals that provide them emotional support under the U.S. Air Carrier Access Act. The act allows a “wide range of service animals” to be permitted in the cabin, from pigs to peacocks. However, most emotional support animals are cats or dogs.
The act acknowledges that these animals can help people with emotional or psychological trauma such as post-traumatic stress disorder.
Airlines are allowed to ask for documentation that shows the animal provides “psychiatric support” for the passenger. However, emotional support animals are not regulated, and their status is only loosely defined.
American Airlines does not require any certification for passengers to travel with an emotional support dog or cat.
The act specifically excludes snakes, reptiles, rodents, ferrets, sugar gliders and spiders.
The Association of Flight Attendants (AFA) condemned the incident as “completely unacceptable and inexcusable” on Tuesday.
“For years, AFA has supported the role trained animals can provide to passengers in the cabin, but we have also called for actions in regard to setting standards for emotional support animals,” the union wrote in a statement.
The AFA called on the U.S. Department of Transportation to take action “so events like the one that happened yesterday do not continue to occur on our planes.”
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Airlines for America tweeted its support for the AFA stance on Wednesday. The group is an industry trade organization representing many of the top U.S. carriers, including American Airlines.