For Manfred Diehl, our Veteran of the Week, the path to the depths of the Pacific Ocean began at a Houston recruiting center on Aug. 11, 1969. It was a date that would bookend his military career; he joined the U.S. Navy under the Cache Program while still in high school, agreeing to a 120-day waiting period before shipping out. When that day arrived, Diehl was flown to Orlando, Florida, to begin 10 weeks of boot camp.
During initial training, Diehl’s aptitude for the complex systems of modern warfare became clear. After qualifying for “A” School, he was stationed at the Navy training facility in Dam Neck, Virginia, to study electronics. Following six months of foundational training, Diehl transitioned to “C” School for instruction on highly specific, classified hardware: the Ships Inertial Navigation System (SINS).
In an era before GPS, the SINS was the heartbeat of a submarine’s stealth. “It’s a system where you tell it where it is, and it will tell you where you are,” Diehl explained. The system functioned by calibrating to a known location on Earth. Once the submarine submerged, the SINS used internal sensors to track every movement and output a continuous, precise location without requiring external signals. For a vessel designed to remain hidden, this self-reliant accuracy was the difference between mission success and catastrophic failure.
After graduating, Diehl moved to Groton, Connecticut, for a six-week course at Submarine School. The training familiarized him with the claustrophobic reality of life beneath the waves and, most critically, how to escape a downed vessel.
After his training was complete, Diehl flew to Hawaii, where he joined the “Gold Crew” of the USS John Adams (SSBN 620). After two months of preparation, he flew to Guam to board the boat. Life on the John Adams was a cycle of intense preparation. Diehl and his shipmates would spend weeks conducting sea trials and making repairs before loading the sub with enough provisions to last 80 days underwater.
Once submerged, the mission was one of deterrent. They patrolled the ocean as a silent sentinel, prepared to defend the United States at a moment’s notice. These patrols typically lasted between 60 and 70 days. Upon returning to port, the transition was swift; it took only four days to turn the boat over to the “Blue Crew” before Diehl flew back to Hawaii for 30 days of Rest and Relaxation (R&R). He repeated this grueling scenario six times with the Gold Crew.
As the John Adams prepared for shipyard refueling and modernization, Diehl faced a choice. Remaining with the boat required reenlistment, a commitment he chose not to make. Instead, he transferred to the USS James Monroe (SSBN 622). He completed one patrol before that vessel also headed for upgrades. Still intent on eventually returning to civilian life, Diehl transferred again to the USS Robert E. Lee (SSBN 601).
By the time he reached the Robert E. Lee, Diehl was a seasoned veteran. He asked his dispatcher how long he would remain on the boat and was told that after one final patrol, he would be transferred to the Pearl Harbor submarine base and likely receive an early discharge.
During that final patrol, Diehl served as the boat’s most experienced SINS technician. The accuracy of the navigation system was vital for the boat’s strategic mission. When the patrol concluded, all navigation records were sent to Johns Hopkins University for analysis.
The results were unprecedented. The captain of the Robert E. Lee was informed it was the first time a George Washington-class submarine had maintained a 100% target accuracy rate throughout an entire patrol. The Executive Officer (XO) attributed this perfection directly to Diehl’s technical mastery.
However, his excellence came with a price. Seeking to keep a talented technician on his crew, the XO secretly contacted the dispatcher and had Diehl’s transfer orders canceled. Diehl, unaware of the maneuver, grew frustrated when his expected orders did not arrive. When he finally reached the dispatcher a month later, he learned his path home had been blocked by his own success.
Diehl was disappointed but stayed focused. He calculated that the next patrol would need to be exactly 60 days to allow him the seven-day window required for discharge upon returning to Hawaii.
The tension of his final days in uniform culminated on a flight from Guam to Hawaii. Mid-flight, the XO called Diehl to the first-class cabin and finally handed him his discharge orders. The relief was so sudden that Diehl skipped back toward his seat.
“Did I see you skipping down the aisle?” a flight attendant asked him.
“Yes,” Diehl replied. He explained he was no longer part of the crew—he was a man on his way out of the Navy. He landed in Hawaii with exactly seven days to spare before his official discharge on Aug. 11, 1975—six years to the day after he first enlisted.
Diehl’s civilian career was equally industrious. He served as a firefighter in Hawaii for four years before joining Lockheed as a technician in California. While working full-time, he earned a bachelor’s degree in software engineering. He eventually moved into management and retired after 35 years with the company.
Today, Diehl enjoys a quiet retirement, though his commitment to service remains. For the past 19 years, he has provided free tax preparation services for his community. It is a humble continuation of a life defined by precision, dedication, and a willingness to navigate the most challenging environments. Good luck Manfred, and thank you for your service! Congratulations on being MCN’s Veteran of the Week.