But one weekend a month, and for two consecutive weeks during summers, Vanderveldt looks after the health and welfare of intrepid F-16 fighter pilots in his role as an Air Force Reserve flight surgeon.

Duality comes easily for Vanderveldt, 40, a private pilot and licensed skydiver who worked as a banking executive prior to becoming a physician. He voluntarily joined the Air Force Reserve last year, due in part to his adventuresome spirit, and in part to patriotism linked to his Dutch heritage.

"My father is an immigrant from Holland," Vanderveldt explains in a University of Miami Hospitals & Clinics exam room. "His family came to this country in 1957 with nothing, except a cargo box full of furniture and family heirlooms."

The Vanderveldt clan prospered during its half century in the United States, so Vanderveldt -- whose nickname is `Dutch' -- felt compelled to give something back. Joining the Air Force Reserve allowed him to do that.

"I feel like I personally owe the country a great debt of gratitude," says Vanderveldt, who earned his undergraduate degree at the University of Tennessee, M.B.A. at Virginia Polytechnic Institute and State University, and M.D. from East Tennessee State University. "And I believe that it's the obligation of every American citizen to find a way to give back to our great country, because that's what made it great.

"Whether you join the reserves, or go to a soup kitchen, or you volunteer at your hospital, you should find a way to give back."

Thanks to his medical training, Vanderveldt entered the Air Force Reserves with the rank of captain. Coming in as a commissioned officer, though, doesn't mean you automatically know how to salute, when to salute, or even how to don your uniform properly.

So in May, Vanderveldt underwent a two-week officer training program at Maxwell Air Force Base, in Alabama, that steeped him in military protocol and customs. Next came rigorous flight training usually given to Air Force pilots and flight crew members.

"We're rated aviators," Vanderveldt says of Air Force flight surgeons. "So I actually had to go through a school where I earned my wings. I had to go through physiological training, to determine whether I had the physical ability to be in an airplane."

The term `flight surgeon' is a bit of a misnomer, because not all of them are surgeons. The common thread is that they've been trained in aerospace medicine and are attached to "air wings" so they can take care of pilots and flight crews.

Vanderveldt passed all the tests, climbing in a centrifuge and enduring the crushing weight of nine times the force of gravity, or 9Gs, on his body. He also was a passenger in a two-seat jet trainer, the T-38, capable of flying 1.3 times the speed of sound.

This month Vanderveldt is slated to ride in something even faster, the two-seat version of the F-16, a single-engine jet capable of 1,500 mph. A far cry from the little 142-mph propeller-driven Cessna 172 aircraft the Knoxville, Tennessee, native is used to flying.

Currently a member of the 482nd MDS medical unit, which is attached to the Air Force's 93rd Fighter Squadron at Homestead Air Force Base, Vanderveldt envisions himself being an Air Force Reserve flight surgeon for the next 20 years, long after his military commitment expires in 2011.

"I love serving in the Air Force Reserve, but I also love being a gastroenterologist at the University of Miami," Vanderveldt says.