Patrick Corcoran was asleep in his bunk about 3:15 a.m. when the USS Frank E. Evans made a wide right turn into the Australian aircraft carrier Melbourne on June 3, 1969.

The 376-foot destroyer was sliced in half during a multinational warfare exercise, and the front half sank in two minutes after months of providing naval gunfire support during the Vietnam War.

Only one body was found. Seventy-three other crewmen were swallowed up by the South China Sea, while 199 survived. Among the dead were Corcoran, 19, of Philadelphia's Torresdale section, as well as five other Pennsylvanians and Earl Preston Jr. of Gladstone, N.J. Yet their names are not among the more than 58,000 inscribed on the Vietnam Veterans Memorial in Washington because the wall's gatekeeper, the Department of Defense, says the men died outside the combat zone.

The Frank E. Evans sank 125 miles from the combat zone, 225 miles off the coast of Vietnam.

For years, Corcoran's family has fought to have the names etched on the wall. Now, nearly 50 years after the  accident, renewed efforts on Capitol Hill are giving hope to the Corcorans, other families, and surviving crew members.

In May, the House attached an amendment to the National Defense Authorization Act, the bill approving funding for the Defense Department, instructing that the names be added. The measure, co-sponsored by U.S. Reps. Adam Schiff (D., Calif.) and Kevin Cramer (R., N.D.), mirrored one in the Senate that failed. That effort was co-sponsored by Sens. Cory Booker (D., N.J.), Bob Menendez (D., N.J.), and Chuck Schumer (D., N.Y.). The amendment will be discussed during a House-Senate conference this month.

Booker said the men "deserve to be remembered and recognized for their courage and service. … Adding their names is an important gesture to honor their memories and show their families our respect and appreciation."

Sen. Pat Toomey (R., Pa.) has worked "for several years" to ensure that the men "receive the recognition they rightfully deserve, including having their names added," said spokesperson Steve Kelly. "He hopes the provision is included" in the final bill.

Not having the names inscribed on the black granite wall has drawn out a tragic memory for some  Evans crewmen and families of the lost. To them, it shouldn't matter where their sons, brothers, and friends died while serving during the Vietnam War.

"They wouldn't have been there if it wasn't for the war," said Tom Corcoran Jr. of Langhorne, Patrick's brother. "Our government won't chisel 74 names on that piece of granite. It's an absolute disgrace. … It's just wrong."

Steve Kraus, then 22, was on the Evans that day and was among the 199 crewmen who survived.

Now 72, Kraus, president of the USS Frank E. Evans Association, has been embroiled in a battle with the Defense Department to get names etched on the wall, but the entire ordeal, he said, has made him "frustrated, kind of hopeless."

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"There have been times where we thought that it was almost a done deal," said Kraus, of Carlsbad, Calif. "Every year, it gets more and more frustrating to know that they're not there. What's worse is that no one seems to want to listen to us." But he said, "We're not quitting."

A request for comment from the Defense Department went unanswered.

In a December 2016 letter to Schiff, the department gave three reasons why it wouldn't allow the names to be added to the wall: The sailors were outside the combat area; the wall lacks available space, and adding the names would compromise a "fundamental aspect of the wall's design and character"; and if it granted the Evans request, it would have to reevaluate all similar cases.

The department offered to put the names on a plaque or panel in a proposed education center near the wall. There's an ongoing campaign to raise $130 million to build the education center.

Heidi Zimmerman, vice president of communications for the Vietnam Veterans Memorial Fund, which engraves names on the wall, said that if the sailors were added, it would break tradition because "there is no space on the wall where these 74 names could be together."

But the department has made exceptions. In 2012, it approved the addition of four sailors whose names were omitted from the wall because they died outside of the combat zone, according to Louise Esola, a Philadelphia native and author of American Boys, about the Evans crash and its aftermath.

While researching for her book, Esola had access to family letters and recordings on the ship.

"To [the families], they died in Vietnam," she said. "Their loss mattered as much as anyone else's during that horrible time in American history, where 300 Americans were coming home in boxes every week."

Since 2003, when the Evans Association first petitioned for the additions, "we've had about three different … bills, and all of those just died in committee," Kraus said.

Independently, the work started for families "when they didn't find their sons on the wall" in 1982, when it was built, he said. Little by little, families found out that the names weren't there.

Memorials that honor the "Lost 74" have been erected across the country. In 1998, the crewmen were honored with a plaque and tree at Arlington National Cemetery.

Patrick Corcoran, who died a year after graduation from Father Judge High School, was added to the Philadelphia Vietnam Veterans Memorial near Penn's Landing in 1988, after a campaign by his father, Tom Sr. The father died in 2006 still hoping Patrick's name would be engraved on the wall in Washington, said Tom Corcoran Jr.

Now, Tom Corcoran Jr. and his sister Suzanne Meissler of Gloucester Township — he was 9 and she was 16 at the time of their brother's death — have picked up where their father left off and are working to get the names onto the wall.

In 2016, Philadelphia City Council passed a resolution urging the Defense Department to recognize the sailors. The resolution called the combat zone boundaries "ill-defined" and said they should not apply because exceptions were made for others who died outside the area.

"Emotions aside, it's about facts, and to these families, their boys went to Vietnam, and on paper they went to Vietnam," Esola said. "This silly combat zone is something for the IRS to sort out. It's not to say whose death counted and whose didn't.

"The proof is there, so it's time for the Department of Defense to fall in line."