The Courageous Civilians of the Corsair Fleet Hunted German U-Boats to Protect US Waters

While the tale of the “ Little Ships of Dunkirk ” is well-known, Great Britain wasn't the only country to rely on its citizens during a crisis. In early 1942, the US military encountered a huge challenge: protecting its extensive coastline from German U-boats with an insufficient number of ships. This predicament resulted in the creation of the Corsair Fleet, a civilian-engaged unit operating under the US Coast Guard.

Looking for a solution to the German U-boat threat

In 1941, Alfred Stanford, commodore of the Cruising Club of America, offered his ships and crews to Admiral Ernest J. King, chief of naval operations. King, a traditionalist, immediately rejected the notion of civilians hunting for German U-boats .

However, the yachtsmen did not back down and generated a public outcry. Numerous letters and newspaper articles advocated for the use of these vessels and their crews, eventually leading King to relent. He placed the volunteers under the command of the Coast Guard, due to their experience with the Auxiliary, a force composed of those too old, young, or unfit to fight.

The Coast Guard Auxiliary typically consisted of unpaid volunteers but could temporarily employ paid members for its main fighting force. In 1941, it had about 7,500 members and 2,000-3,000 craft, most suitable only for inland or coastal operations. The Auxiliary’s main responsibilities included supplementing the main Coast Guard force, conducting safety inspections, performing lifesaving efforts, and patrolling coastal beaches for spies and saboteurs.

Establishment of the Coast Picket Force - AKA Corsair Fleet

In May 1942, the Coastal Picket Force (CPF) was established. The CPF was designed to use auxiliaries and their ships as a screen, to keep German U-boats from gaining access to the coastal shipping of the eastern United States. However, organizing a such a large force proved too much for untrained civilian volunteers, and the foolhardy adventurers were put under direct control of the Coast Guard.

The sailors, fishermen and yachtsmen had what they wanted: approval for, and a method to create, a fleet of sailing and motor yachts, which could take the fight directly to the U-boats. While officially known as the CPF, they more-commonly went by the moniker, Corsair Fleet.

Layout of the Corsair Fleet

The Corsair Fleet was divided into six groups, from the north Atlantic down to Florida. Manned by crews made up everyone from college students to experienced and skilled fisherman, the picket ships patrolled a designated square of 15 nautical miles along the 50-fathom line of the Atlantic seaboard. This often meant cruising more than 150 miles off the coast.

This came as a rude awakening for many of the less-experienced sailors, who were expecting relaxing summer cruises, not the rough seas of the deep Atlantic. However, the ships were sound and seaworthy, often the famous racing yachts of wealthy New Englanders or the fishing schooners of their blue collar counterparts.

Upon arriving at base, each ship was stripped of its civilian embellishments and painted battleship grey, with a Coast Guard designation. That being said, this was as far as military discipline and uniformity went in this ragtag group of foolhardy men.

Hunting German U-boats off the US East Coast

Despite their lack of decorum and military style, the ships of the Corsair Fleet proved to be effective at their task. The wooden-hulled sailing vessels were particularly useful. The U-boats' advantage was their ability to submerge, but doing so limited their view. To supplement this, they used sonar to listen for other ships - something that worked in the CPF's favor. A ship under sail makes little-to-no noise below the surface, unlike a diesel motor or steam engine.

This made the CPF vessels much harder to detect, allowing them to get close to the enemy and gather a more accurate report on their position. The lack of noise pollution also allowed them to use sonar much more effectively. Though this backfired at times, one ship, Valor , called in an airstrike on a U-boat, which turned out to be their misidentified refrigerator engine.

The Corsair Fleet was highly effective

Despite this lack of discipline or military skill, the ships proved to be highly effective. John Kimball, a carpenter on Actaea , shared one account of how effective they could be. While cruising, the crew located a German U-boat. They were faced with a difficult decision: break radio silence and give their position away or keep themselves safe while risking the rest of the American merchant fleet.

The brave crew took the first choice and radioed in the submersible's position. The entire crew huddled around the radio, not knowing what would happen next. To their surprise, the U-boat dove and fled. This proved to be a psychological shift for the German submariners along the East Coast. It was no longer open season - they were being watched.

Another instance showed the effectiveness of a line of Corsair Fleet ships, when four of them became involved in the sinking of a single U-boat. First spotted by CGR- 1923 , the vessel was next reported by CGR- 2516 . That evening, she was spotted by CGR 2503 .

Finally, the U-boat's position was picked up by a Civil Air Patrol (CAP) flight, which dropped a smoke bomb. The smoke was seen by CGR- 4436 , which sped to the location and dropped depth charges. An oil slick was seen, and this became the only possible kill by the CPF.

This operation also exemplified the combined-arms method of U-boat hunting, which had proven so effective. By the time the German vessel was hit, she'd been chased by four CPF ships, five CAP aircraft, four US Navy aircraft, two Navy vessels and a Navy blimp. While it took a lot to sink a single submersible, doing so likely saved scores of lives and hundreds of tons of precious cargo or fuel.

The Corsair Fleet didn't just hunt German U-boats

The Corsair Fleet didn't just there to hunt U-boats - the ships often assisted in rescues and retrieving lost cargo. The USS Pioneer rescued the crew of the tanker ST R.M. Parker Jr . when she was torpedoed in late 1942, while CGR- 355 was able to recover much of the ordnance from the freighter SS Benjamin Brewster around the same time.

By the end of 1943, the U-boat threat had significantly diminished and, along with it, the need for the CPF. The operation was severely downsized, but not disbanded until the end of the Second World War .

It's difficult to say exactly how effective the CPF was, as its ships had no confirmed kills. That being said, it did become clear they won on the psychological front. Their presence off the East Coast meant U-boat crews knew they couldn’t safely cruise the surface at night. On the flip side, the merchant seamen the Germans were targeting knew that, if they sank, there was likely a CPF ship nearby that would rescue the survivors.

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The story of the Corsair Fleet has, for the most part, faded into distant memory. However, their ability to bring the fight directly to the German U-boats not only broke the myth of a submersible's invulnerability while cruising, but proved to be a useful deterrent for any enemy ship wanting to torment American shipping lanes.