Story highlights James Sizemore and Howard Andre Jr. were shot down over Laos in 1969

The remains of the majors weren't discovered until April

The nonprofit Warrior Aviation provided the private flyover at Arlington

Two U.S. Air Force officers who died in a crash in Laos in 1969 were laid to rest Monday at Arlington National Cemetery and honored with a final flyover -- but not one provided by the U.S. military.

Citing budget concerns, the Air Force denied a request to honor the fallen service members with a military flyover. That prompted a private air squadron to step in.

"Unfortunately, the government hasn't been able to supply flyovers for these gentlemen that have served and gave up the greatest sacrifice they could, so all of us have decided to go ahead and fulfill the mission," said Calvin Peacock, a volunteer with nonprofit group Warrior Aviation

Maj. James Sizemore of Lawrenceville, Illinois, and Maj. Howard Andre Jr. of Memphis, Tennessee, were shot down in their A-26A Invader aircraft during a reconnaissance mission over Laos during the Vietnam War, according to the Defense Department. The pilots were considered killed in action.

The crash site was discovered in 1993, but the pilots' remains were not discovered until April. Military scientists then matched the remains with the dental records of Sizemore, solving the 44-year-old mystery and bringing closure to the families.

A flyover is a military ceremonial ritual reserved for the most esteemed of fallen service members. The Department of Defense refused a military flyover for Sizemore and Andre because of the forced budget cuts known as sequestration.

The private squadron consisted of a B-25, two P-51s, four L-39 jets and an A-26 Invader, the same type of plane Sizemore and Andre flew. The Warrior Aviation organization is comprised of volunteers, most of whom are veterans.

"People like myself, the Vietnam generation, we know what sacrifice these guys made. It was a true honor to be a part of the group that is allowed to do this. When they asked me to do this, I said, 'Absolutely, it would be a honor, '" said Warrior Aviation volunteer Larry Kelly.

The Defense Department records indicate that more than 1,640 American military personnel are still unaccounted for from the Vietnam War.