(CNN) If you'd seen him in the crowded room that night, you might not have given him a second look.

He was the frail old man in a wheelchair. He wore a black ascot cap, a burgundy tie and a gray tweed jacket that covered his 140-pound frame. Ba Van Nguyen couldn't speak, could barely move; just a tiny man in a roomful of big Navy men swapping war stories.

But rewind the clock 40 years, slap a pistol in Nguyen's shoulder holster, add about 10 pounds of wiry muscle, and strap him into the seat of a military helicopter armed with an M60 machine gun and he becomes something else:

A total badass.

On April 29, 1975, Nguyen did something that could have been ripped from the script of a "Mission Impossible" movie. He was fleeing from the North Vietnamese army with his wife and their three young children as communist soldiers crashed the gates of Saigon. For 20 excruciating minutes, Nguyen's copter literally hovered between life and death over the South China Sea as a group of astonished U.S. Navy sailors watched from the deck of a nearby ship.

"We couldn't figure out how he did it; he was a Houdini," said Hugh Doyle, the chief engineering officer aboard a U.S. naval ship that encountered Nguyen at sea.

Snippets of Nguyen's story have been told before. "The Last Days of Vietnam," a riveting documentary, which aired on PBS this week, shows photographs of Nguyen's Houdini maneuvers. A book, "The Lucky Few: The Fall of Saigon and the Rescue Mission of the USS Kirk,'' also explores Nguyen's exploits.

But what happened to Nguyen after his "Mission Impossible" escape hasn't been explored. In some ways, what he did when he came to America was just as impressive.

'I knew my dad was coming'

Nguyen was no hero on the morning of April 29, 1975. He was desperate. He was just one of thousands of South Vietnamese who were trying to flee the country as the North Vietnamese steamrolled into Saigon.

The U.S involvement in Vietnam had officially ended two years earlier with the signing of the Paris Peace Accord. But American civilian and diplomatic personnel in Saigon were being evacuated to U.S. naval ships in the South China Sea and hordes of South Vietnamese were trying to hitch a ride. Many were soldiers like Nguyen, a major in the South Vietnamese Air Force. If captured, they faced execution and the dispersion of their families to brutal work camps.

Nguyen, though, had a plan. He moved his family to his mother-in-law's house in a residential neighborhood in Saigon, and he told his wife, Nho, to start packing. He would return in a CH-47 Chinook, the largest helicopter in the South Vietnamese Air Force. The distinctive whump whump whump of a Chinook could be heard from miles away.

"If you hear a Chinook coming, get ready," Nguyen told his wife.

Miki, Nguyen's oldest son, slept under his bed the night before his family's escape. He could hear the crackle of machine guns and whistling missiles as the North Vietnamese drew closer, but he remained confident.

We couldn't figure out how he did it; he was a Houdini. Hugh Doyle, chief engineer USS Kirk

"I knew my dad was coming," he says in the documentary "The Last Days of Vietnam."

Miki heard the Chinook the next morning. He grabbed some clothes and baby milk for his 10-month-old sister, Mina, and sprinted to the Chinook with his family and several of his dad's friends. Once inside, he heard his father say that he saw U.S. helicopters headed out to sea. They had to be landing somewhere.

"Let's see how this goes," Nguyen said as he steered the helicopter to the South China Sea, just as an ominous red light appeared on the dashboard indicating that the craft was running low on fuel.

Once at sea, Nguyen turned on his radio's emergency frequency and heard the chatter of American naval officers. Someone in the helicopter spotted a U.S. Navy ship below. It was the USS Kirk, and it had a landing deck. Nguyen steered the Chinook to the Kirk.

The Kirk was led by Capt. Paul Jacobs, dubbed "Big Jake" by his crew. He was a straight-talking, no-nonsense New Englander who stood 6-foot-3. He had orders to shoot down any unidentified aircraft that might threaten the aerial evacuation from Saigon.

Jacobs could have ordered the destruction of Nguyen's aircraft, but he took a chance. He figured Nguyen was a South Vietnamese soldier fleeing for safety. The sky was buzzing that day with South Vietnamese pilots ferrying their family and friends to U.S. ships in stolen military helicopters.

"Unless somebody shoots at us, we ain't shooting," Jacobs told his crew.

Nguyen radioed the Kirk as he slowly approached. He spoke little English, but the Kirk had a sailor who spoke rudimentary Vietnamese. In his book, "The Lucky Few," the author Jan Herman recounted Nguyen's desperation. He told the Kirk's radio operator that he had women and children aboard, and he was running out of fuel.

"I must land or crash into the sea," Nguyen said. "Please help us."

The Kirk's crew tried to wave Nguyen away. Its landing deck was too small for the Chinook. If Nguyen tried to land, the Chinook's blades could tear into the ship, killing passengers and crew.

Nguyen had an idea. He radioed the Kirk that he would hover just above the deck. Then he would order his wife and three children to take their chances by jumping out of the helicopter, into the arms of sailors. Kent Chipman was one of those sailors waiting below. He was a Texas native with a droopy mustache who everyone called "Chippy." He weighed only 130 pounds, and wondered if he was big enough to break the fall of the Chinook's passengers. As he held up his arms, he had a thought:

This is going to be bad

Ba Van Nguyen's helicopter smashes into the water after he risks all to save his wife and their three children.

Nguyen deftly steered the Chinook over to the fantail of the ship, keeping the copter's rotors clear of the ship's superstructure. A sudden gust of wind, a wrong nudge on his part, and the blades could tear into the ship, killing his family and the crew.

His co-pilot opened the door. He motioned to Nguyen's wife, Nho, that women and children should go first. Miki jumped first, followed by his little brother. Then Nho grabbed her infant daughter, extended her arms, and dropped her to the sailors below before jumping as well. Kirk sailors caught all of them; no one was injured.

Nguyen was now alone in the Chinook. How could he safely get on the Kirk as he wrestled with the 12-ton helicopter? He had another idea. He would attempt something that he had never tried before -- a ditch at sea. He flew the helicopter a safe distance from the Kirk and hovered for about 10 minutes as his wheels dipped in and out of the water.

Chipman watched what Nguyen did next from the deck of the Kirk.

"This is crazy; he's taking off his clothes," Chipman thought to himself as he watched Nguyen.

Somehow Nugyen took off his flight suit and his shoulder holster -- all while working various sticks and controls to keep the massive helicopter stationary. One pilot who watched it said he couldn't figure out how Nguyen undressed while keeping the Chinook stationary. Nguyen then rolled the helicopter with its whirring blades to the right, away from the ship. As it began to tumble over and hit the water, he jumped into the sea.

The impact sounded like a train wreck. Jagged shrapnel from the helicopter's blade whistled by the Kirk. The helicopter then turned upside down in the water, its wheels pointing upward. There was an ominous silence as the crew watched something red spread across the spot in the sea where Nguyen jumped.

No one could see him. Then someone spotted a tiny head as it bobbed to the surface. Nguyen was alive. He had managed to somehow dive under the water when the Chinook hit. The red liquid was hydraulic fluid.

The crew on the Kirk exploded with applause, whistles and cheers.

"Attaboy!" one said.

Photos: The Vietnam War Photos: The Vietnam War South Vietnamese troops wade through water to flush out communist rebels, known as the Viet Cong, in 1962. Several years earlier, North Vietnamese communists began helping the Viet Cong fight South Vietnamese troops. They wanted to overthrow the South Vietnamese government and reunite the country, which split in 1954. Hide Caption 1 of 30 Photos: The Vietnam War On July 21, 1954, Vietnam signs the Geneva Accords and divides into two countries at the 17th parallel: the communist-led north and U.S.-supported south. Vietnam had been a part of the colonial empire French Indochina until communists in the north began fighting France for control of the country. Hide Caption 2 of 30 Photos: The Vietnam War A man appears fearful as he is questioned by South Vietnamese soldiers in August 1962. Hide Caption 3 of 30 Photos: The Vietnam War American planes drop napalm on Viet Cong positions in 1962. Hoping to stop the spread of communism in Southeast Asia, the U.S. also sent aid and military advisers to help the South Vietnamese government. The number of U.S. military advisers in Vietnam grew from 900 in 1960 to 11,000 in 1962. Hide Caption 4 of 30 Photos: The Vietnam War U.S. troops in Vietnam salute the coffins of seven American soldiers who were killed in a helicopter crash circa 1963. Hide Caption 5 of 30 Photos: The Vietnam War Hide Caption 6 of 30 Photos: The Vietnam War Thich Quang Duc, a Buddhist monk, burns himself to death on a street in Saigon -- the capital of South Vietnam -- on June 11, 1963. He lit himself on fire to protest alleged persecution of Buddhists by the South Vietnamese government. Hide Caption 7 of 30 Photos: The Vietnam War A father holds the body of his child as South Vietnamese Army Rangers look down from their armored vehicle in March 1964. The child was killed as government forces pursued guerrillas into a village near the Cambodian border. Hide Caption 8 of 30 Photos: The Vietnam War The U.S. Navy destroyer USS Maddox, seen here, was anchored in the Gulf of Tonkin when it was attacked by the North Vietnamese in August 1964. After U.S. President Lyndon Johnson falsely claimed that there had been a second attack on the destroyer, Congress passed the Gulf of Tonkin resolution, which authorized full-scale U.S. intervention in the Vietnam War. Johnson ordered the bombing of North Vietnam in retaliation for the Tonkin attack. Hide Caption 9 of 30 Photos: The Vietnam War A South Vietnamese reconnaissance unit walks hip-deep in water as a U.S. helicopter skims over reeds in the Mekong Delta in October 1964. They were on the lookout for Viet Cong guerrillas. Hide Caption 10 of 30 Photos: The Vietnam War Injured people receive medical aid after an explosion at the U.S. Embassy in Saigon on March 30, 1965. Hide Caption 11 of 30 Photos: The Vietnam War A suspected Viet Cong is kicked by a South Vietnamese soldier in October 1965. The prisoner was one of 15 captured in a raid near Xom Chua. Hide Caption 12 of 30 Photos: The Vietnam War Women and children crouch in a muddy canal as they take cover from intense Viet Cong fire at Bao Trai, about 20 miles west of Saigon, in January 1966. Hide Caption 13 of 30 Photos: The Vietnam War Staff Sgt. Harrison Pell, a wounded American soldier, drinks from a comrade's canteen during a January 1966 firefight between U.S. troops and a combined North Vietnamese and Viet Cong force. Hide Caption 14 of 30 Photos: The Vietnam War A Viet Cong soldier holds an anti-tank gun during the Tet Offensive, a massive surprise attack launched in 1968 by the North Vietnamese. The attack hit 36 major cities and towns in South Vietnam. Both sides suffered heavy casualties. Hide Caption 15 of 30 Photos: The Vietnam War South Vietnamese Gen. Nguyen Ngoc Loan, chief of the National Police, fires his pistol into the head of suspected Viet Cong officer Nguyen Van Lem on a Saigon street on February 1, 1968, early in the Tet Offensive. Hide Caption 16 of 30 Photos: The Vietnam War A young refugee carries an elderly woman on his back while crossing a bridge in Hue, Vietnam, in 1968. Hide Caption 17 of 30 Photos: The Vietnam War Troops look at the aftermath of an attack on the U.S. Embassy in Saigon in 1968. Hide Caption 18 of 30 Photos: The Vietnam War A U.S. Army first sergeant guides a medevac helicopter through the jungle to pick up casualties suffered near Hue in April 1968. Hide Caption 19 of 30 Photos: The Vietnam War A South Vietnamese woman mourns over the body of her husband, which was found with 47 others in a mass grave near Hue in April 1969. Hide Caption 20 of 30 Photos: The Vietnam War U.S. President Richard Nixon points to a map in the White House after telling the nation that American troops have attacked, at his order, a communist complex in Cambodia in April 1970. Nixon ordered troops to invade border areas in Cambodia and destroy supply centers set up by the North Vietnamese. Hide Caption 21 of 30 Photos: The Vietnam War On May 4, 1970, National Guard units fired into a group of anti-war demonstrators at Kent State University in Ohio. The shots killed four students and wounded nine others. Anti-war demonstrations and riots occurred on hundreds of other campuses throughout May. Hide Caption 22 of 30 Photos: The Vietnam War U.S. artillerymen relax under a crudely made peace flag at the Laotian border in 1971. In February 1971, U.S. and South Vietnamese troops invaded southern Laos in an effort to stop North Vietnamese supply routes. This action, ordered by President Nixon, was done without consent of Congress, and it led to more anti-war protests. Hide Caption 23 of 30 Photos: The Vietnam War South Vietnamese forces follow after terrified children after a napalm attack on suspected Viet Cong hiding places in June 1972. A South Vietnamese plane accidentally dropped napalm on South Vietnamese troops and civilians. The terrified girl in the center had ripped off her burning clothes while fleeing. Hide Caption 24 of 30 Photos: The Vietnam War North Vietnamese Foreign Minister Nouyen Duy Trinm signs a ceasefire agreement in Paris on January 27, 1973. The last American ground troops left in March of that year. Fighting would resume between North and South Vietnam, but the United States did not return. Hide Caption 25 of 30 Photos: The Vietnam War Air Force Lt. Col. Robert L. Stirm, a released prisoner of war, is greeted by his family in Fairfield, California, as he returns home on March 17, 1973. Hide Caption 26 of 30 Photos: The Vietnam War A cargo net lifts refugees from a barge so they can be evacuated from the city of Da Nang, Vietnam, on April 1, 1975. Hide Caption 27 of 30 Photos: The Vietnam War Mobs of Vietnamese people scale the wall of the U.S. Embassy in Saigon on April 29, 1975, trying to get to a helicopter pickup zone. A day later, South Vietnam surrendered to North Vietnam when North Vietnamese troops entered Saigon. Saigon is now called Ho Chi Minh City in honor of the late North Vietnamese leader. Hide Caption 28 of 30 Photos: The Vietnam War A CIA employee helps Vietnamese evacuees onto a helicopter near the U.S. Embassy in Saigon on April 29, 1975. Near the war's end, about 100 Marine, Air Force and Air America choppers evacuated an estimated 7,000 Americans and South Vietnamese out of the South Vietnamese capital in under 24 hours. It was the largest helicopter airlift in history. Hide Caption 29 of 30 Photos: The Vietnam War U.S. President Barack Obama stands at the Vietnam Veterans Memorial in Washington in May 2012. The black granite memorial bears the names of more than 58,000 Americans killed in the Vietnam War. Hide Caption 30 of 30

"Did a beautiful job," said another.

A motorboat from the Kirk was dispatched to pick up Nguyen. He was brought on board wearing nothing but the red boxer shorts his wife had made for him and a white, floral shirt. The gold bars he had placed in his pockets were gone.

"He wanted immediately to be reunited with his family," said Doyle, then the ship's chief engineer.

A snippet of film footage shot by various crew members showed Nguyen right after his narrow escape. He stood next to Jacobs, coolly nodding as both made small talk. His body was still and his demeanor unruffled; you'd never imagine he had just escaped death and saved his family.

The Kirk would go on to rescue a ragtag flotilla of South Vietnamese naval ships, merchant ships and fishing boats. Jacobs and his crew would eventually save 30,000 South Vietnamese refugees.

Today, Jacobs says his crew was skillful, but they were also lucky. The South China Sea was notoriously rough; 20-foot waves and nasty winds were common. Yet the sea was placid that day.

"God was looking out for us, because for several days we had seas as flat as a flounder," he said.

Chipman never forgot Nguyen's coolness under pressure and the relief he felt when he successfully caught the pilot's infant daughter and wife.

"It was a happy ending to a shitty war," he said.

'He was a bit modest'

A 10-month-old Mina Nguyen cries after she is dropped into the arms of a sailor after her father's high-risk escape.

It was a bittersweet ending, though, for Nguyen. He had saved his family but lost everything else -- his money, status, extended family and his country. He moved to Seattle with his family and eventually found a job as a technician with Boeing. He took on his new life with the same tenacity and resourcefulness that he relied on over the South China Sea.

He painstakingly learned the English language. He worked as a janitor at night while going to electronics school during the day. When he got a job at Boeing, he awakened at 4 every morning and was out the door a half-hour later. A family in a Lutheran church helped sponsor his family. Still, six months after he arrived in the United States, he took his family off government assistance, telling them the United States was the land of opportunity.

He just didn't want to take; he wanted to give back. He told his family they were going to become U.S. citizens within five years so they could pay taxes and vote. From his children, he expected stellar grades and told them college was non-negotiable. He would pay their way if they earned good grades.

At times, he trained his children like they were crew members aboard his Chinook.

He'd rouse them from their bed every Saturday morning with a list of household cleaning tasks. If they finished their homework early, he'd give them new math problems to teach them to take their time.

"If we transposed the wrong number, he would erase the entire page and we had to start from the beginning," said Mina, the infant girl who was dropped from the Chinook.

He was as fiercely protective of his youngest daughter as he was when he flew her to safety.

When Mina began dating a musician, who would eventually become her husband, Nguyen had a man-to-man talk with him.

"You're not good enough for my daughter," he told him. "Why don't you have a doctorate? She has a doctorate."

Ba Van Nguyen, left, with his wife, Nho, and sons Miki and Mika and daughter Mina, not long after surviving their dangerous passage to America in 1975.

Yet Nguyen was not an inflexible taskmaster. He liked to have fun. His children said he relished living life to the fullest, knowing that he had been given a second chance. He loved to fish, play piano and host karaoke parties at his home. And he could maneuver on the dance floor as well as he could in a helicopter. He loved to dance the rhumba and the cha-cha.

And if his children complained, they'd hear The Speech:

Your mother and I came to the United States with nothing but my drawers," he'd tell his children. "Look at where we are today. We are not wealthy. But we are not poor."

The family's improbable journey to the United States moved into the realm of myth: It was no longer a story to be swapped over the dinner table, but something that distilled the values they admired.

"This is our Ellis Island story," Miki said.

When Nguyen retired from Boeing in 2000, Miki knew what to give his father. He presented him with a display case that held the red boxer shorts his father wore during their family's escape.

Nguyen's reaction to the gift was understated. He accepted the box without a word. He did write an account of his family's ordeal once for a Vietnamese-language newspaper, but only in the third person. He didn't tell readers he was the pilot.

"He didn't want to brag," Miki said. "But he knew he did a badass thing."

The hero unmasked

Others knew it, too, and they were determined to unmask this modest Vietnamese hero.

I knew my dad was coming. Miki Nguyen, son of Maj. Ba Van Nguyen of the South Vietnamese Air Force

Over the years, the captain of the USS Kirk occasionally wondered about the pilot who ditched the Chinook at sea. The question turned into a mission. In 2009, Jacobs went on a Vietnamese television show and asked if anyone knew about such a pilot.

The search was on. The South Vietnamese community in the United States is tight. And one day, Miki received a chain email citing Jacobs' inquiry. He responded via email:

"If you're looking for the Chinook pilot, that's probably my dad."

A flurry of phone calls followed. Jacobs and his former crew were holding a reunion on July 10, 2010, at a conference center in Springfield, Virginia. They invited Nguyen. He was not the same man he was in 1975. He'd suffered the loss of his middle son, Mika, who died from a brain hemorrhage in 2003. And after retiring from Boeing, Nguyen had developed Alzheimer's. He used a wheelchair. He couldn't speak, save for moans and guttural noises.

When Nguyen reunited with the Kirk's crew, his wife was steering him this time. She pushed him in a wheelchair to the hotel ballroom, accompanied by their son and daughter. As they made their way down a hallway, the first Kirk crewman she saw was "Chippy" Chipman, the sailor who had caught her and her infant daughter as they jumped out of the helicopter years ago.

Nugyen saw Chipman as well. His eyes welled up; he was on the verge of tears.

"He was staring at me and I was staring at him. He knew and I just knew," Chipman said.

Chipman approached Nguyen and saluted. He told him who he was and what he did. He looked at Miki, who was now a jovial grown man.

"I'm the guy who caught you," he said in his Texas drawl.

Kent "Chippy" Chipman reunites with Mina Nguyen, who was just 10 months old when he helped save her life.

Miki was too stunned to say anything.

Then he looked at a resplendent Mina, who stood beside her father. He told her that he was determined to catch her when she fell out of the helicopter even if meant his life.

"I was proud," Chipman said of seeing Mina. "I don't have children, but it was like seeing your long-lost daughter all grown up. She did well for herself."

The reunion turned into a tribute to Nguyen. The Kirk crew showed color film footage of Nguyen's escape. Various Kirk crew members had taken amateur photos and film that day.

Mina looked at photos of her chubby infant face pressed against the Plexiglas of the Chinook as it circled the Kirk. She saw the photo of herself landing in the arms of Chipman.

"Chills went up my spine," she said.

She then watched the footage of her father's escape.

"This is something like Tom Cruise," she said. "To think it was my own father. To think it was my own family that jumped out one at a time. It baffles my mind."

Miki had his own thoughts. For years, he had admired his father's modesty. He understood it. Many South Vietnamese people who came to the United States after the war just wanted to forget the trauma of the past. They had lost status, rank, their family, their money -- they just wanted to focus on the future.

The result, though, was that families were in danger of losing their past. Their children grew up in the United States without learning about their family's exodus. And now those stories were fading as his father's generation passed on.

"The only difference between my family and others is that we had film and video," Miki said. "Every other Vietnamese refugee came here and had a very colorful and very difficult story."

Miki watched as Jacobs walked before the crowd in the hotel ballroom.

"We saved the best for last," he said as he looked at Nguyen.

Jacobs read a citation honoring Nguyen for his stunning airmanship. It praised his outstanding skills as a pilot, his "calm under extraordinary pressure," and said his actions reflected well on South Vietnam and "are in keeping with the highest traditions of the United States Naval Service."

Nguyen could say nothing as he watched from his wheelchair. A Navy officer bent down and pinned an air medal for bravery on his jacket.

Nguyen started to squirm in his wheelchair. Miki, who was behind his father, wondered what he was trying to do.

Nguyen would die from Alzheimer's three years later, at 73, passing away in his sleep one summer night. But at the reunion, in that moment, time folded back to April 1975. Miki watched his father do something that reminded him that, though his father's body was failing, the dad who he knew would come for him was still there.

Nguyen shuffled to his feet from his wheelchair, straightened his jacket as he looked at Jacobs, and, with a trembling right hand, he saluted.