TALLAHASSEE, Fla. — As more Americans begin traveling by air for the first time since the pandemic began, they're encountering more flight cancellations and, in some cases, the disappearance of routes they once depended on.

The root cause, most travel experts argue, is an acute and growing pilot shortage.

Taking shape over the course of the last decade, the shortage has been exacerbated by the exodus of more than 5,000 seasoned pilots who were offered early retirement packages by airlines that were hemoraging cash in the early days of the pandemic.

A relatively swift rebound in passenger traffic took many airlines by surprise and has forced them to dramatically ramp up pilot hiring.

The gulf between supply and demand is expected to exceed 10,000 pilots annually by 2023, making for a pilot's market the likes of which the aviation industry has rarely ever seen.

Commercial pilots are required by the FAA to have 1,5000 flight hours for Airline Transport Pilot certification. As more of those qualified pilots sign on with the airlines, their jobs as flight instructors, corporate aviators and even pipeline patrol pilots are increasingly being backfilled by up-and-coming pilots, many of whom never previously considered a career in aviation.

Cole Vickerman is one of them, having obtained his private pilot certificate more than 20 years ago. When 9/11 happened, he hung up his wings and went to Afghanistan.

"For me, at my age, a lot of guys joined the military, and then shortly after that, that's when I joined, because the country was in a different state then," he said.

Today, he's back at his home airport, training for his instrument rating and soon his commercial pilot certificate.

A heavy equipment mechanic by training, Vickerman says the aviation hiring boom prompted by the airline pilot shortage has him thinking about turning his love of flying into a career. For years, he explained, the thought of shuttling people and equipment by air becoming "just a job" was enough to keep the idea at bay. But things have changed.

"I don't know if that would happen though," he said. "I think doing it for a living, whatever route I go, I think I'd love it, to be honest with you."

And he's not alone. Flight schools have been reporting marked uptick in new students.

Many are interested in becoming airline pilots, a years-long process that can cost in upwards of $80,000, but others are intrigued by the idea of earning a private pilot certificate to fly themselves to destinations near and far, often for no more than the fuel cost of a large SUV.