SAN DIEGO – Clayton Schenkelberg, who experienced one of the most fateful days in modern U.S. history, the Dec. 7, 1941, attack on Pearl Harbor that shoved the United States into World War II, died April 14 at a senior care facility in San Diego.

At 103, he was believed to be America's oldest Pearl Harbor survivor. Born a year before the Spanish flu swept the country, his final year included a run-in with COVID-19. He caught it but didn't get sick, according to family members.

A Navy torpedoman at a submarine base, Schenkelberg volunteered to drive a train loaded with the underwater missiles away from strafing Japanese airplanes. Then he ran to an armory, grabbed a rifle and started shooting back.

After the war, he stayed in the Navy for another two decades, got married and raised seven children, and eventually settled in San Diego, where he had a second career as a high school custodian.

His motto through the years: one day at a time.

"If you asked him about any of it, he would tell you he was just doing what needed to be done," his son Patrick said. "He didn't think it was anything special. He had a job to do and he did it."

Born Oct. 17, 1917, in Carroll, Iowa, Schenkelberg knew hardship early on. His mother died when he was 9. The stock market crashed when he was 12, triggering the Great Depression. When he was 17, his father, a livestock salesman and grain-elevator operator, was killed in an accident.

In 1937, he followed an older brother into the Navy and was sent to Pearl Harbor and into torpedo work. On the morning the Japanese planes attacked, his shift was just ending. He was looking forward to spending the day with his girlfriend.

Of the roughly 50,000 American service members on Oahu that day, about 2,400 were killed and another 1,200 injured. More than 30 ships and hundreds of airplanes were destroyed or damaged.

The survivors picked themselves up, helped win the war and then got on with their lives in a way that's led them to be dubbed the Greatest Generation. There is no official roster of how many are still alive.

"I would say less than 100," said Stuart Hedley, 99, who for decades has been San Diego's most active and visible survivor, giving talks, visiting schools and riding in parades.

That estimate includes four men with ties to the now-defunct Pearl Harbor Survivors Association chapter in San Diego. At its peak, with almost 600 members, it was thought to be the largest chapter in the nation. When it shut down two years ago, it was believed to be the last one still operating.

Hedley said it's his understanding that Schenkelberg had been the oldest survivor in the country. Patrick Schenkelberg said various officials in recent years told him that was the case, too.

If so, it was a badge he wore modestly. At various memorial events, he routinely deflected attention from himself. "We're still paying our respects to those who didn't make it," he said in 2016 during the annual Pearl Harbor Day remembrance at the USS Midway Museum.

He retired from the Navy in 1967 and worked for nearly 20 years as a school custodian.

"He was an outstanding gentleman, very humble, and always ready to lend a hand," Hedley said. "I'm honored to have called him a friend."