SAN ANTONIO -- Retired Air Force Brig. Gen. James Burwell, one of the first military aviators to fly using cockpit instruments, died recently at age 100.

Burwell was trained in instrument flying at the Army Air Corps' Kelly Field, later Kelly Air Force Base, and he later devised courses to teach others.

"Back in the early '30s, the Air Force hadn't learned how to fly with instruments," Jim Keck, a retired Air Force lieutenant general and a longtime Burwell friend, told the San Antonio Express-News. "First they had to convince pilots they needed instruments and could trust them. ... (Burwell) was a pioneer."

A native of Tarboro, N.C., Burwell died on June 25, less than two weeks before his 101st birthday. His wife, Marcine, said he was alert and in good health until he suffered a stroke three months ago.

After retiring from the Air Force in 1956, Burwell traveled the world, but didn't go back to work as a pilot, his wife said.

"He was ready to hang up his wings," she said.

Burwell was one of two surviving graduates of the West Point class of 1926, said Keck, also a West Pointer.

Last year, at his 100th birthday celebration, Burwell attributed his longevity to "peace of mind."

"I think that was pretty accurate," Keck said. "He didn't sweat the small stuff."

Burwell was a member of the Order of Daedalians, an organization of military pilots. His decorations include the Legion of Merit with oak leaf cluster.

A memorial service will be held Tuesday morning, with burial to follow at Fort Sam Houston National Cemetery.