Monday, May 19, 2025
John T. Diehlmann Jr., a World War II veteran and longtime Seaford resident who worked more than four decades as an electrical engineer at Sperry Gyroscope, died on April 7. He was 101.
Born on Aug. 9, 1923, in Brooklyn, Diehlmann grew up in the Bushwick neighborhood with his younger brother, Elten. He began working at Sperry while attending Cooper Union at night to study electrical engineering.
Although eligible for deferment during World War II, Diehlmann voluntarily enlisted in the Army Air Corps at age 19. He served in the China-Burma-India theater, flying the perilous "Hump" airlift missions over the Himalayas to supply Allied forces.
After the war, he returned home and completed his degree. He married Jean, his childhood sweetheart, and the couple moved to Seaford in 1954, where they raised three children.
Diehlmann continued his career at Sperry Gyroscope until his retirement in 1982. He and Jean traveled the country in retirement, often towing their boat for fishing trips and visiting friends.
His son, John Diehlmann III, said his father enjoyed fishing and gardening, with some of his favorite trips taking him out to Montauk.
“He lived a long, healthy, happy life,” he said “He was very independent, which he insisted on doing just about for the last couple of days.”
In later years, Diehlmann served as caregiver to Jean following her Alzheimer’s diagnosis, tending to her needs for nearly a decade before her passing.
“My mother passed from Alzheimer's, and he did not want her in a hospital or facility, so he spent nine years caring for my mother, until towards the end, they had hospice come in,” said his son. “But he would spend three hours feeding her to make sure she got nourishment when she couldn't feed herself or didn't even want to eat. That always impressed me, that he took such good care of his wife and my mother.”
Family members described Diehlmann as principled, independent, and sharp-witted, with a love for practical jokes and a strong devotion to family. His son said those traits were passed down.
“He allowed us to make a lot of our own decisions, whether they were right or wrong, and if they were wrong, then he would correct us after the fact,” he said. “He was a great role model because he was a hard worker, and he instilled that in myself and my sisters.”
Diehlmann’s son said he hopes people remember his father as “a humble, hardworking, loving and caring person who enjoyed life, who lived every day like there was going to be no tomorrow.”
He is survived by his children: John and Mary Diehlmann, Elaine Diehlmann, and Debbie Mariner; seven grandchildren; and four great-grandchildren.
Diehlmann was a proud member of the Seaford American Legion for 35 years. Known for his warmth and camaraderie, he made a point to shake every member’s hand and greet them by name at the start and end of each meeting. In 2023, the Legion honored him and fellow World War II veteran Gary Iorio—who also passed away this year—with a joint 100th birthday celebration at the post, recognizing their service and longstanding contributions to the Seaford community.
The Seaford American Legion conducted a memorial service for him at Charles G. Schmitt Funeral Home earlier this month, conducted by Past Post Commander Bill Hoehn and Chaplain Charlie Wroblewski. Also in attendance were members of the American Legion Riders from Elmont Post 1033.
