Wendt, NASA's so-called "Pad Fuhrer," died early today of congestive heart failure. He was 86.
Wendt's daughter Norma Kay Wendt confirmed his death to AOL News. "He was a great dad," Wendt said. "He was very supportive of everything that we had done." She jokingly called her father "a benevolent dictator with very little benevolence."
The German-born engineer served as the pad leader for the manned Apollo moon program and the Gemini and Mercury missions. In that position, Wendt was responsible for the last-minute safety checks of each launch.
"We came to trust his judgment and place our safety in his capable hands," Wally Schirra, who flew on the Mercury, Gemini and Apollo missions, once said.
Wendt's no-nonsense approach to missions gained him praise from astronauts and scientists who said they felt safer knowing he was in charge. And they gave him the "Pad Fuhrer" nickname.
"It's easy to get along with Guenter," Gemini astronaut Pete Conrad joked, as the space site Collect Space noted. "All you have to do is agree with him."
"When he was there, things went extremely well," NASA spokesman Allard Beutel told AOL News. "He made a name for himself at a time when we had a lot of strong personalities and characters."
Roger Launius, senior curator for the Smithsonian's National Air and Space Museum, said Wendt's obsession with safety made him a popular figure. "I don't think they feared him. I think they respected him a great deal," Launius told AOL News. "He was very well known as a fellow who was in charge."
Wendt was born Aug. 28, 1923, in Berlin. After serving as a technician with Hitler's Luftwaffe, Wendt was among the German scientists who came to the United States after the war and worked on the U.S. space program.
In his 2001 memoir, "The Unbroken Chain," Wendt wrote about the job he loved.
"Simply put, in an emergency the buck stopped with me," he wrote.