Three days past his 24th birthday and six days into his first combat tour, Warrant Officer Ralph Allen Dunn's UH-1 Huey helicopter crashed into the jungles of Vietnam. It was June 29, 1964. His mother, Oral Allen, feels the pain of that day, every day. For five decades of Memorial Days Allen has mourned her boy Ralph, Colorado's first casualty of the Vietnam war. "They came to the door with a telegram," she remembered during a break from the volunteer work she's been doing for more than 20 years. That volunteer work, nearly 25,000 hours spent helping out at Penrose-St.