This article originally appeared in the March 2018 issue of Military Officer.

Whether you're an adrenaline junkie or a passionate volunteer, there are many ways to make your post-working life personally rewarding. Here's how Lt. Col. Art Nalls, USMC (Ret), did it.

When Nalls retired from the Marine Corps in 1998, he didn't leave his love of flying behind. As he pursued a career in real estate investing, the likelihood of sitting in a cockpit again seemed remote. Still, Nalls kept up with the flight community, attending monthly Marine Corps Aviation Association meetings. After squirreling away some cash, he made an unusual private purchase: a Russian Yakovlev Yak-3 fighter.

The World War II-era aircraft was the first of five former military planes he would eventually own.

“It was a thoroughbred, a rocket ship that took a while to learn how to land. I'd have two landings that were good and then one that absolutely scared the crap out of me,” Nalls explains. “But at a cocktail party, an old Navy [landing signal officer] explained how to land. … And when I did it and coasted it to an easy turnoff midfield, … I [felt] invincible.”

A 1939 Piper Cub and L-39 Albatross jet followed, but Nalls missed his favorite plane from his Marine Corps days - the AV-8A Harrier. In 2005, he began wondering if he could get his hands on one, and the timing couldn't have been better: The Royal Navy was starting to decommission its Sea Harriers.

“We made a call to the FAA and asked [if it was possible to fly one as a civilian] and they said, 'Yeah, no one has done it before, but we think there's a path forward for you,' ” Nalls says.

So he bought one. The FA2 Sea Harrier was stripped of its weapons and military navigation and communications systems, and Nalls shipped it - in pieces - to St. Mary's County, Md., where he keeps his planes. It took two years to reassemble it.

Nalls later started a business, Nalls Aviation, which performs at air shows. With jet fuel alone costing up to $100 per minute, this is not a revenue-generating venture. But Nalls Aviation certainly keeps its founder on the young side of 64.

“I work seven days a week. … My blood pressure is good. I pass the FAA physical. I have … bad knees, but nothing keeps me from flying.”

This year, Nalls bought a second Harrier, a two-seat training aircraft. He'll use it to work with other pilots and support a DoD contract. He expects to keep flying for at least another decade and urges other retirees to think big after their military careers.

“If it's your dream, follow it,” he says.