During the time of his enlistment Vietnam had become a focal point in the Cold War and the fight against the spread of communism. Congress had recently signed the Gulf of Tonkin Resolution and the U.S. commitment to supporting South Vietnam was escalating rapidly.

Hegdahl was soon deployed to Vietnam onboard the USS Canberra. This was a guided missile cruiser that provided naval gunfire support and surveillance against North Vietnamese forces.

On the early morning of April 6th, 1967, the USS Canberra was patrolling the waters of the gulf when Hegdahl came up on deck for some fresh air. What happened next is not exactly clear.

Some reports say that Hegdahl was trying to retrieve his hat when he fell into the water. Other versions say that the concussion of a missile being fired nearby knocked him into the water.

Perhaps the concussion of the missile launch knocked the hat from his head and he fell in the water trying to get it. Whatever the case, Hegdahl fell into the Gulf of Tonkin as his ship steamed away, leaving him stranded.

He managed to stay afloat for several hours until North Vietnamese fishermen eventually found and rescued him. Despite being an enemy combatant, the fishermen displayed unexpected kindness and compassion for him.

Hegdahl was reported missing when he failed to appear at the 11:30 muster. After searching the ship twice, he was officially listed as “missing as a result of being lost at sea.”