By Matt Petrillo

PHILADELPHIA (CBS) — It took nearly 80 years but a World War II hero was buried with full military honors. The burial happened at Arlington National Cemetery on Tuesday morning. The burial included an Air Force flyover.

Eyewitness News Matt Petrillo talked to the Philadelphia man who discovered his remains a half-century after he died.

Alfred Hagen wasn’t yet born when a U.S. Army Air Corps B-25 bomber plane went missing in Papua New Guinea during World War II more than 75 years ago.

“They were designed to bomb, like in a European theater, to bomb cities or military targets,” Hagen said.

Hagen, a contractor known for building offices in Philadelphia, spends his spare time searching around the world for missing servicemen. The search for this bomber was personal for Hagen because the pilot, Maj. Bill Ben, is Hagen’s great-uncle.

“Several members of my own family went missing in the second World War. So the pain of not knowing what happened in a loved one has stayed with me,” he said.

The plane crashed into the mountainside of Papua New Guinea in January 1943.

Hagen never found his great-uncle’s remains. But in 1998, he did find the plane. He also discovered the remains of a co-pilot on board, Maj. Donn Young.

But Young’s remains were not confirmed until recent DNA testing.

Now, more than 75 years since the deadly plane crash, Young was buried Tuesday at Arlington National Cemetery with full military honors. Hagen says it was his honor to be there with Young’s family.

“There’s just a special emptiness in mothers and fathers and siblings and children that stay behind and never know an answer. It’s not that they think of it 24 hours a day, but there’s a hole in their lives. This time it was grieving with a sense of closure,” Hagen said.

No one knows exactly why the plane crashed. Hagen says the left engine was lost during a thunderstorm. But Young’s family feels fortunate to get closure. Many of them attended Young’s funeral on Tuesday morning at Arlington National Cemetery.