The war was closing in. Hour by hour, North Vietnamese and Viet Cong soldiers tightened their grip on Saigon. Their artillery shells fell, like heavy footsteps, across the restive city.
In the chaos, a C-5A Galaxy cargo plane took off from Saigon-Tan Son Nhut Airport as part of "Operation Babylift" - a mass evacuation of children from South Vietnam.
Jim Zimmerly was one of scores of babies on the aircraft climbing over the South China Sea on April 4, 1975 when locks on a rear loading ramp failed and cargo doors blew open explosively.
The crew almost nursed the plane back to the airport but crash-landed in a rice paddy, where Zimmerly was one of 175 survivors. A total of 138 died, including 78 children.
The humanitarian exodus 40 years ago had gotten off to a tragic start, but 25 other baby-lift flights followed during the month and more than 2,500 children under age 10 were evacuated to the United States and other countries, including Australia, France, and Canada.
The effort will be remembered April 25 at the New Jersey Vietnam Veterans Memorial and adjacent Vietnam Era Museum in Holmdel, Monmouth County, with a 21-gun salute, dedication of a plaque honoring the C-5A casualties, readings from a new play about the baby lift, and a program of speakers, including parents and adoptees.
It came 10 years after the deployment of U.S. ground forces in Vietnam. Sunday marked the 50th anniversary of that milestone.
"Every day, I feel lucky to have survived, and I know it will always be part of my life," said Zimmerly, 40, a tax consultant, who lives in St. Charles, Mo. "I'm fortunate to have gotten out of the country to live in the U.S. with a caring and loving family."
Zimmerly had been left at an orphanage by his birth mother, who was unable to care for him. He has twice returned to Vietnam and visited with his mother, who died a couple years ago. "I wanted to see what it was like and how my life could have turned out," he said. "It was a revelation."
His adoptive American mother, Wanda Zimmerly, still recalls anxious moments four decades ago, waiting for news of him at her home near St. Louis. "I heard what the morning after the plane crash," she said. "I was hysterical."
A couple of days later, the baby boy was accompanied on other aircraft that brought him to the United States and eventually St. Louis, where the Zimmerly family gathered at an airport to welcome the new addition.
"It was exciting," said Zimmerly, 75, who plans to attend the free Holmdel event with her son and others from across the country and the world. "The whole family was there; we were ready for him."
Making such adoptions possible was an army of volunteers in service organizations such as the Friends of Children of Viet Nam. LeAnn Thieman of Fort Collins, Colo., was on a runway at Tan Son Nhut, loading babies for Australia, when she watched the C-5A crash.
While the war raged nearby, she helped arrange the evacuation of 300 children, many of them in cardboard boxes that doubled as makeshift cribs. She also waited to be assigned her own baby.
"The third day I was [in Saigon], I looked across a room filled with babies and saw a 9-month-old boy standing next to a crib," said Thieman, 65, a nurse and author of This Must Be My Brother, a book about the baby lift, and Chicken Soup for the Soul - The Joy of Adoption. "He took one look at me and got down on his hands and knees, crawled across the room to my pant leg, stood up and clung to my leg.
"I picked him up and that was it," said Thieman, who also plans to attend the Holmdel event. "I knew he was destined to be our son."
One of the first gifts for Mitch Thieman - who is now 40 and lives in Austin, Texas - was a T-shirt with the words "All-American Boy."
His life-changing story has been repeated by many children evacuated in April 1975. Kim-Lan "Pu-Lani" Carlson was abandoned near a Saigon orphanage and later flown to Michigan, where her adoptive family became a single mother and grandmother.
"God is so faithful," said Carlson, 40, a Frisco, Texas, mother who works as a real estate office client manager by day and runs a Christian dance studio by night. "He provided a way for me to be on this side of the ocean.
"I'm living the American dream," she said. "I always say, I'm a survivor and now I'm a thriver."
Carlson has two biological sons, 14 and 16, and a daughter adopted from Vietnam, 10.
"I had the privilege of going back to my homeland three times in the past 10 years, and it's still so very poor," she said. "We don't realize how rich and blessed a nation we have."
Among the baby-lift infants was Heather Noone, one of many children who were sick and malnourished. Her adoptive mother, Lana Mae Noone, had been told that Heather was on the flight that crashed, then got word she was on the way.
The baby girl arrived April 23, 1975, but soon died of pneumonia. "I promised Heather two days before she died that I would make sure Babylift was never forgotten and her short life would not be in vain," said Noone, 68, a Garden City, N.Y., resident who helped organize the Holmdel event.
She agreed to take another girl - one of the last to leave Saigon before it fell. The baby, Jennie, is now 40 and married to a website designer at the United Kingdom consulate in Saigon.
"From my teenage years on, I gave a great deal of thought about the infinite number of ways that being a Vietnamese adoptee has affected my life and the lives of the people around me," wrote Jennie Noone as part of a family-published book, Global Mom: Notes From a Pioneer Adoptive Family. "I've realized how grateful I am to have such accepting parents."
The baby-lift stories - including the Noone family's - will be portrayed in readings from a play called Children of the April Rain.
"When you hear this play, you will realize the amount of people involved in getting the children out," said actress Ashley Adelman of Infinite Variety Productions of New York. "It shows the incredible things that it took to get them here."
For some like Lana Mae Noone, the airlift still seems like a miracle. "I don't think there has been anything like it," she said. "My joy came out of someone else's grief.
"No children should be separated from their birth moms, but because of that I became a mom," she said. "I just know those children had to be evacuated, and everyone involved was an unsung hero."