Five puppies learning to be assistance dogs had a howling good time during a training exercise at Detroit Metropolitan Airport.During the Tuesday training, the quintet of pooches and their trainers walked through a Transportation Security Administration checkpoint, rode an elevated tram and boarded an airplane.It was all part of an effort to acclimate the dogs to one of the many settings they may experience later in life. The training was led by Paws With A Cause — a Wayland, Michigan-based nonprofit that oversees the custom training of puppies that become assistance dogs for people with disabilities. The group pairs puppies with volunteers who raise and socialize the dogs for the first year of their lives."Eventually, when they're placed with our clients, they may well need to fly with them," said Liz Hood, who coordinates foster puppy curriculum for the organization. "So, if they have this exposure now while they're young, then it means it's not going to be a big deal for them when they're with their clients when they're older."The trainers also take the puppies to grocery stores, libraries, restaurants and doctor's appointments, Hood said. But the airport provides a unique experience because of its distinct sights and sounds.The five puppies — Labrador and golden retrievers, and a papillon among them — bounded through the airport, earning more than a few quizzical glances from airline passengers. The dogs shuffled down a jetway and onto a plane, where they nestled at the feet of their trainers, who were seated and provided the pups with treats to stay still."One of the main reasons for doing this type of training is so that our puppies become calm and confident in all types of different social situations," Hood said.