NAVAL AIR FACILITY ATSUGI, Japan — John Hornbrook III made the leap few sailors do in a Navy career and found out it wasn’t much of a leap at all.

Hornbrook last year was promoted to commander, a commissioned-officer rank that only a small percentage of former enlisted sailors achieve.

But the 30-year Navy veteran, who joined the service a few months shy of high school graduation, said his ascent through the officer corps was seamless compared to the sheer leap from petty officer 1st class to chief petty officer.

“It’s night and day,” he said.

The uniform changes, from blues to khakis, and on goes the CPO anchor insignia. One joins an elite military circle and is thrust into the role of leader: “Your whole enlisted career you’ve been told if you have a problem, go to the chief, the chief will take care of it,” Hornbrook said.

“Now you’re the chief.”

Hornbrook’s journey to commander began in small-town America. As a teenager in Angola, Ind., he earned $1.65 an hour at an automobile dealership washing and detailing cars, pumping gas, changing oil and working in the parts room. Unsure of what he wanted to do with his life, he knew what he didn’t want: a dead-end job in the landlocked Midwest.

“I thought I better do something rather than hanging around town,” he said. “And I wanted to see the world. I’m still seeing the world.”

Hornbrook followed in the footsteps of his grandfather and father, who both served in the Navy, the elder Hornbrook in World War I, and his father in the Korean War.

He enlisted in 1973 as a junior storekeeper, assigned to the USS Bristol County in San Diego.

Eight years later, he made chief; three more, senior chief.

An officer commission was more elusive. His application for the Navy’s Limited Duty Officer program was denied twice. He was selected on his third try in 1986 — after 12 years in the Navy.

“I wasn’t going to give up until there were no more opportunities,” he said.

Today, Hornbrook, 48, is the supply officer for Commander, Fleet Air, Western Pacific, in charge of aviation supply for 7th Fleet bases and others in the western Pacific. Before that, he was NAF Atsugi’s supply officer for four years.

Hornbrook credits his rise through the enlisted and officer ranks with determination combined with a strong work ethic. He earned an associate’s degree in 1983, finished his bachelor’s degree in 2002 and remains an avid runner.

But today’s Navy is smaller than it was 30 years ago and competition for promotion is tougher, Hornbrook said. The new “Perform to Serve” program may make it easier for some sailors to advance in overmanned ratings, he said. Others “may not exactly get the job they wanted, but they’re going to be able to stay in the Navy and make a career out of it, and that’s the whole goal.”

Enlisted sailors who want to be commissioned officers should feel confident of their leadership ability, Hornbrook said.

“We have an advantage because we have prior enlisted experience,” he said. “You should be able to make some smart decisions because of the things you learned when you were enlisted.”

Petty Officer 1st Class Pat Layug agreed. Layug, a storekeeper who worked for Hornbrook in Atsugi’s supply department, said he “is a very good leader.

“He used to be one of us. He knows how the enlisted guy works.”