There are many reasons someone would fly with a miniature horse, disability experts say. Although a growing number of emotional support animals have emerged in recent years, in the case of miniature horses, their function as service animal is primarily physical, said Kenneth Shiotani, a senior staff lawyer at the National Disability Rights Network.

For some blind people, such as Confetti’s owner, guide horses serve as a compelling alternative to guide dogs.The animals are mild-mannered and fast learners, with nearly 360-degree vision. They may also offer balance support to individuals with physical disabilities.

Mona Ramouni, who has more experience traveling with a miniature horse than perhaps anyone else in America, pointed out that training a service animal takes thousands of hours. “With a dog you’ll get eight to 10 years if you are lucky,” she said, adding that “with a horse you get 35, 40 years.” Ms. Ramouni’s own horse, Cali, is 14. “She’s just getting to middle age,” she said.