Anti-Sub Warfare by Avi Heiligman

Forgotten Her es Anti-Submarine Warfare

By Avi Heiligman

The German U-505 with an American flag after her capture The sinking of German submarine U-175 by USCGC Spencer in 1943 USS Fanning

Over the course of history, world powers needed to have a strong military to keep their influence steady. Naval power is a key component of a powerful nation. Navies have always looked for new and better ships and weapons to add to their arsenal. For centuries, the idea of having an underwater ship was floated around by inventors, and over the course of the 19th and 20th centuries, it developed into a major part of navies worldwide.

World War I was the first war that submarines were used on a major scale and were a big threat to surface ships. It took a concentrated effort to coordinate the anti-submarine effort. American anti-submarine warfare units saw a lot of action during the two World Wars. Here are some of their operational stories and missions that rarely made the front pages.

While American submarines didn’t see a lot of action, anti-submarine units were busy thwarting the German U-boat menace. The U.S. entered World War I in April 1917, and its warships had several encounters with German subs. Then, early on the morning of November 17, 1917, the coxswain on destroyer USS Fanning sighted the German submarine U-58. The U-boat had been sighted when she surfaced her periscope to line up a torpedo shot on a British merchant ship. The Fanning and her sister ship USS Nicholson were on escort duty, and the Fanning launched three depth charges. These charges caused some damage to the German sub, and the Nicholson joined the Fanning by shooting their deck guns. These shots caused the U-boat to lose steering, and soon her crew surrendered to the American surface ships. This marked the first time in war that American ships had sunk an enemy submarine in battle. Anti-submarine warfare (ASW) at first was very primitive as surface ships had to wait for the submarine to surface. The subs needed to surface to navigate, recharge or resupply, and these provided the best opportunities to attack enemy subs. Later on in the war, depth charges (explosives set to explode and cause damage to ships underneath the water’s surface) became sophisticated enough that they could be set to explode at a specific depth after being rolled off a rack on a surface ship. Manned balloons and airplanes were used to spot enemy ships but weren’t equipped to destroy submarines. Echo-ranging technology was then developed, and this proved useful in detecting ships underwater. Anti-submarine mines proved the most effective way to sink U-boats, as 58 were sunk using this method during World War I.

After World War I, the technology on subs became more sophisticated, and they came up with tactics to avoid ASW. By the onset of World War II in 1939, submarines were able to dive deeper and could go silent so as to not make any sound or signal that could be picked up by any other ship in the area. If they did make noise, sonar (sound navigation and ranging) could pick up the signal and an alert would go out to surface ships that an enemy sub was in the area.

Both the Japanese and Germans had large and powerful submarine fleets and had better torpedoes than the American Navy (the story of these faulty torpedoes is one for the military blunders column and had devastating results during the first two years of the war for the Americans in the Pacific). The Battle of the Atlantic lasted the entire length of the war and one of the main components of the battle pitted German U-boats against Allied merchant convoys and their escort ships. At first, it was not going well as German U-boats prowled the East Coast and were sinking merchant ships at an alarming rate. This prompted the Americans to have their ships sail in convoys and had warships accompany them on their journey. This tactic didn’t always work, as the warship crews were not very familiar with this type of warfare. As time went on, they gained valuable experience, and as more warships were coming out of the shipyards, the tide began to turn.

One of the main tactics in anti-submarine warfare was the use of escort carriers or “baby flattops.” These were smaller than the average aircraft carrier and carried around 30 planes. They were the nucleus of hunter killer groups that included destroyers armed with depth charges and a new type of anti-sub weapon called hedgehogs.

The USS Bogue was the trendsetter for escort carriers in the Atlantic and has the distinction of sinking subs from multiple countries. She sank 11 German U-boats and one Japanese sub. One of her screening ships, the destroyer Badger, sank another U-boat. The Badger, along with three other destroyers that were part of the group, sank a thirteenth sub. The Bogue received the coveted Presidential Unit Citation for her actions during the Battle of the Atlantic.

Off the coast of Morocco the USS Guadalcanal had located an enemy sub and sent a destroyer to deploy depth charges. This caused the U-505 to surface as the charges created cracks in the valves and pipes. Her captain thought that she was about to sink and ordered the crew to abandon ship. The American carrier captain realized that the submarine was not sinking and sent a boarding party. They found valuable intelligence including codebooks and a highly prized enigma coding machine on board. Salvage parties then prepared the captured submarine for towing to a Axis submarines with varied results. In addition to sending off groups of ships in convoys, ships were built specifically to meet the submarine threat. Corvettes, frig-

The U-505 was the first enemy ship captured on the high seas by the U.S. Navy since the War of 1812.

navy base at Bermuda. The U-505 was the first enemy ship captured on the high seas by the U.S. Navy since the War of 1812. After the war, she was donated to the Chicago Museum of Science and Industry, where she is on permanent display.

A lot of tactics were used against ates and destroyer escorts all were equipped with anti-submarine devices. Aircraft also played a major role, and there were air raids on German submarine pens located on the French coast. Planes with longer range were introduced and flew overhead to locate potential threats lurking right below the ocean’s surface. Cracking the Enigma code was vital for intelligence as Allied code breakers were able to track U-boat movements. The successes against German and Japanese submarines were not immediate but eventually the submarine threat diminished.

Anti-submarine warfare grew out of necessity, and many of the weapons and tactics used today were first developed during the two World Wars. Anti-submarine technology and methods saved many lives during the wars and continues to protect our sailors in service today.

Avi Heiligman is a weekly contributor to The Jewish Home. He welcomes your comments and suggestions for future columns and can be reached at aviheiligman@gmail.com.