How Does Sonar Work? It Depends on Your Need for Stealth
The art of using sound to fight underwater.
BY KYLE MIZOKAMI
PUBLISHED: JAN 25, 2023
In the early days of World War II, Allied navies faced a stark challenge: how to detect Germany’s growing fleet of u-boats and prevent them from repeating the havoc wrought in World War I. While German submarines extracted a horrifying toll in the years between 1939 and 1945, a new technology—sonar—gave the Allies an important tool in locating and sinking Axis submarines. Today, sonar has evolved into a sophisticated military tool used by everything from submarines to helicopters, stalking both surface and subsurface targets, and all with one goal: dominance of the world’s oceans.
How Sonar Was Invented
In the final days of World War I, the British and French navies were desperate to stem losses from German u-boats. The Kaiser’s submarines, in an attempt to disrupt the Allies’ economies, had sunk 30 percent of merchant shipping worldwide. A new type of sensor, the Allied Submarine Detection Investigation Committee (ASDIC) device, involved detecting submarines through the use of sound. Unfortunately this system—later known as sound navigation and ranging, or SONAR—was not ready in time to materially affect the war.
It would be another twenty years, during World War II, when sonar would prove invaluable in the hunt for the new generation of u-boats. Sonar allowed Allied sub-chasers, corvettes, frigates, and destroyers to detect even submerged submarines, then attack them with depth charges and other anti-submarine weapons. Sonar as a detection device was further refined during the Cold War, as the Soviet Union quickly established superiority in its sheer number of submarines, threatening a new third Battle of the Atlantic.
https://www.popularmechanics.com/military/navy-ships/a42557088/how-does-sonar-work/
