While Douglas was working with Fairchild, he met Evelyn Shoemaker, who worked in the Fairchild factory, said Carolyn Alexander, a family friend.
The two married Aug. 4, 1956.
McRoy joined the U.S. Air Force after graduating from high school in 1943, his brother said.
Robert McRoy remembers when he and his brother heard about the bombing of Pearl Harbor.
The two were in Los Angeles, trying to fly one of Douglas' model airplanes.
"He was a great model airplane builder," Robert said.
They heard news about the attack over someone's radio. Two years later, Douglas was training to be an Air Force pilot, his brother said.
By the time Douglas had his pilot's license, the war was over, but he spent the next 20 years flying for the Air Force.
In one of Douglas' more notorious moments, he accidentally dumped his flying instructor out of an airplane while training in San Antonio, Texas, Robert said. The instructor wasn't belted in, and when Douglas went to turn the plane, the instructor fell out of the open cockpit. The instructor parachuted to safety, but the incident made newspapers from New York to Los Angeles, Robert said.
While in the Air Force, Douglas was stationed everywhere from Hagerstown to Iceland to Japan. During the Korean War, part of his mission was to fly the wounded home to Hawaii from Korea, his brother said. He also flew 18-hour recognizance missions over Alaska during the Cold War, Robert said.
During the 1950s, The Morning Herald reported that McRoy flew a new wing from Fairchild to Texas in a Flying Boxcar. Pictures show part of the wing was hanging out of the cargo area during the entire trip.
Douglas retired from the Air Force as a major. He went to college on the GI Bill and earned a bachelor's degree at the University of Maryland, College Park.
He spent the next 23 years at the University of Maryland, working as a technical adviser for the College of Education, Carolyn said.
"He loved electronics," she said.
Douglas and his wife returned to Hagerstown after he retired, Carolyn said. Evelyn Shoemaker McRoy died in 2003.