Sonar technology comes to grips with dangerous new submarine era

Anti-submarine warfare (ASW) efforts face a militarily resurgent Russia, a strengthening China, and proliferating quiet diesel-electric submarines that could shift the global naval balance of power.

During the last five days of October 1962, U.S. Navy warships, guided by surface, sub-surface, and airborne anti-submarine warfare (ASW) sensor data, launched numerous practice depth charges at Soviet submarines violating the Cuban Missile Crisis blockade. The actions were in accordance with the “Submarine Surfacing and Identification Procedures” released earlier that month.

ASW technology at the time included AN/SSQ-23 Julie, AN/SSQ-57B LOFAR (Low Frequency Acquisition and Ranging), and AN/SSQ-28 Jezebel sonobuoys, magnetic anomaly detection (MAD), radar, SQS-26 sonar, and SOSUS (Sound Surveillance System).

The Soviet submarines were seen as a threat to U.S. ships enforcing the blockade and as possible transports for nuclear warheads. The threat was considered so significant that Attorney General Robert Kennedy said “the President ordered the Navy to give highest priority to tracking the submarines and to put into effect the greatest possible safety measures to protect our own aircraft carriers and other vessels.”

On the other side, Soviet Premier Nikita Khrushchev warned a visiting American businessman that Soviet submarines would attack any American ship that stopped a Soviet ship.

Despite having received a copy of U.S. naval orders limiting “signaling” to practice depth charges, many Soviet submariners believed they were under real attack. That misunderstanding was compounded by American military belief that all Soviet subs in the area were armed only with conventional weapons. It was not known until decades later that Soviet submarine commanders were under orders to launch nuclear-tip-ped torpedoes against any U.S. warship trying to force them to surface-and two captains ordered those weapons assembled and prepared for launch before deciding to stand down.

It was the greatest exercise of ASW technologies and capabilities since the end of World War II and the last time the U.S. Navy used force (even if only practice depth charges) against a foreign submarine.

Cold War legacy

While ASW was a major element in the Cold War, other than the Cuban blockade, it was in the form of “hide-and-seek” engagements between the U.S. and Soviet navies. With the collapse of the Soviet Union and end of the Cold War three decades later, the U.S. became the world’s only superpower, facing no adversarial blue-water navy.

That began to change in the 21st Century with dramatic increases in Chinese military spending (building a major submarine force as part of its evolving blue water fleet), the re-emergence of aggressive Russian military activity (building new submarines), hostile actions by the North Korean navy (and its small fleet of small subs), and even the broad use of “semi-submersibles” by Latin American drug cartels.

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