(NewsNation) — Multiple pilot errors caused an Osprey crash in Australia that killed three Marines in August 2023 during a near midair collision, a military investigation has found.

Crew chief Cpl. Spencer R. Collart, 21, was among those killed as he “heroically re-entered the burning cockpit of the aircraft in an attempt to rescue the trapped pilots.”

Now, he will be posthumously awarded the highest non-combat honor the military can award: The Navy and Marine Corps Medal. It’s given to those who risk their lives for acts of heroism.

Osprey crash investigation report

The Osprey crash that took Spencer Collart’s life was one of four that have occurred in the past two years, catching Congress’ attention. The report also blamed squadron leadership for ignoring flight safety.

The incident involving Spencer Collart exposed serious safety issues with the Osprey aircraft.

Last week, Alexia and Bart Collart endured a visit from Marines who came to their Arlington, Virginia, home to brief them on the investigation results as to what caused the Osprey crash.

But they weren’t expecting to hear these words: Your son didn’t die in the crash.

Spencer Collart’s final act of bravery

Spencer Collart had safely escaped the aircraft. But the 21-year-old saw that the Osprey’s two pilots were unaccounted for. Despite the smoke and flames, he went back in.

Bart Collart wasn’t surprised his son tried to save the pilots.

“Spencer died a hero,” Bart Collart told NewsNation’s Nick Smith on “Morning in America” Wednesday.

He explained that his son jumped back into action despite surviving the initial crash. Spencer Collart tried to save his fellow crew members Capt. Eleanor LeBeau and aircraft commander Maj. Tobin Lewis.

“He thought the world of both pilots and their abilities,” Bart Collart said. “We’d like to give some credit to the pilots for bringing that thing down in such a way that all 20 Marines in the back of that aircraft survived the crash.”

He continued, “I think Spencer made the call. He thought he could go in there and save them. And unfortunately, he was overcome by flames and didn’t make it back out.”

Spencer Collart had been standing in the tunnel even as the plane went down. Most of the 23 troops on board escaped out the back, including a commander who told investigators he saw Spencer Collart escape out a side door.

A site team later found Spencer Collart’s tether — what he’d use to latch onto the Osprey to move around during flight — undamaged outside the aircraft.

Investigators believe he may have unbuckled Lewis from his restraints before succumbing to the fire and smoke.

Spencer Collart’s dedication to service

“Our first thoughts were, ‘You silly, silly, brave man. Why did you go back in?’ But I know why he did,” Bart Collart said. “He wanted to save him, and I can’t, I can’t blame him one bit.”

Spencer Collart was a goal-driven, 6-foot-2, grinning Washington Liberty High School lacrosse player who walked into the house on his 18th birthday with a surprise: He’d just enlisted.

The Collarts weren’t a military family, but Spencer wanted to serve. And he wanted to fly.

He got his top assignment choice and met his two best friends, Lance Cpl. Evan Strickland and Cpl. Jonah Waser. They spent a year together training to become crew chiefs, enlisted Marines responsible for the aircraft and its passengers. There’s a photo of them posing with their class on April 22, 2022, the day they earned their wings.

They were flying the V-22 Osprey, which functions as both an airplane and a helicopter. But it’s an aircraft that has a troubled history and four fatal accidents in two years.

In June 2022, Strickland was killed along with four other Marines in a training crash in California. Spencer Collart served as a pallbearer. He stayed in close touch with Strickland’s family, calling to check on them, Facetiming them on the crash anniversary, and reading the accident investigation report from cover to cover, Strickland’s mother, Michelle, said.

“He wanted to really understand,” she said.

‘A match made in heaven’

Spencer’s family met Waser for the first time at the funeral. This time it was Waser who put on dress blues to serve as a pallbearer and escort his best friend’s remains from Dover Air Force Base to Arlington National Cemetery.

Spencer’s younger sister, Gwyneth Collart, felt instant chemistry. Her parents saw it too.

“If there’s ever a match made in heaven, this is the one,” Bart Collart said.

Gwyneth Collart and Waser married July 6 in Arlington and held their reception at Top of the Town, a ballroom that has a terrace overlooking Arlington National Cemetery. They could see the section where Spencer Collart was buried, and Gwyneth Collart pinned her brother’s portrait to her bouquet.

The Associated Press contributed to this report.