"In December 1941 one of the "best kept secrets" of the U.S. Air Force was born. It may sound a bit biased, but that's exactly how Lawrence Kinch explains the birth of the Civil Air Patrol. "The CAP goes back to the week of December 1941 when we basically were giving serious thought of going to war," said Kinch, a lieutenant colonel of the patrol's Thames River Composite Squadron of the Connecticut Wing. The squadron is stationed at the Groton-New London Airport. "We had activated our primary pilots to go to war and then needed people back home to carry messages, blood and other necessities. We became a civilian auxiliary," he said. Back then, in addition to carrying military supplies and sometimes personnel, between bases, the patrol was also charged with tracking enemy submarine activity along the East Coast." Read more here: The Day - Civil Air Patrol was born in World War II | News from southeastern Connecticut
I was a CAP cadet in the 1960s. We were taught how CAP volunteers sunk two U-Boats. I think that post-war research has reduced this to zero.