Awfully Slow Warfare

Frustrated by the pace of antisubmarine warfare in the network-centric age, the Navy is bringing new technologies into play

By RICHARD R. BURGESS, Managing Editor

“We’re going to change ASW — awfully slow warfare — to a time-centric context.” Adm. John B. Nathman, speaking as vice chief of naval operations to a Capitol Hill audience at a Lexington Institute symposium on air power in January, signaled his intention to challenge the stubborn, century-old paradigm of antisubmarine warfare (ASW) as a plodding game of cat and mouse, with periods of hours and even days elapsing from initial detection to destruction of a hostile submarine.

Having assumed command of U.S. Joint Forces Command in February, Nathman is in charge of developing fleet-wide doctrine and tactics in all areas of naval warfare. As a fighter pilot whose career matured in the cockpit of supersonic F-14 and F/A-18 fighters, he knows something about rapid detection, targeting and destruction of targets, an art perfected in the 1980s against the Soviet bomber threat. He similarly wants to shorten the detect-to-engage timeline for ASW.

ASW is difficult primarily because of the opaqueness and distorting effects of the ocean and the unpredictability of the sea floor. Although the atmosphere can distort radar signals, the effect is negligible compared to the vexing distortions of sound in the ocean. ASW is complicated even further in the littoral environment, where detecting the engines, motors, propellers and generators of submarines is hampered by denser shipping traffic, greater ocean noise and shallow-bottom effects on sound propagation.

The targets expected in the littoral environment also are more difficult to detect. The diesel-electric submarines — many of them modern and exceptionally quiet — that equip potential adversaries are easy to hide in the noisy littoral environs. These submarines are potential threats to the access the United States desires to achieve through its evolving sea-basing strategy, designed to minimize reliance on foreign ports by using ships and other platforms for striking adversaries and maintaining presence.

“Sea basing is all about access. ASW is about protecting our sea base,” said Capt. William Toti, head of doctrine development and requirements for the San Diego-based Fleet ASW Command and officer in charge of the command’s detachment at Joint Forces Command.

To address these challenges, the Navy’s Task Force ASW, chartered by Adm. Vern Clark, chief of naval operations, has developed a concept of operations for the 21st century — that Clark approved in December — “intended to guide the development of a comprehensive ASW Master Plan.” In the near term, the Navy’s goal under the concept is to leverage technical advances in such areas as acoustic processing, data collection and sharing, communications, rapid maneuver and precision engagement.

In the long term, the Navy wants to build an integrated network of sensors coupled to standoff weapons to maximize advantages in speed, persistence and precision.

The Navy’s current ASW capabilities largely were developed during the Cold War. Toti told Seapower of a common misperception about ASW in that era.

“The truth is we did not do ASW in the Cold War; what we did was surveillance and monitoring. There is a large component of the ASW kill chain that went untested. What we’re trying to do is change the mindset of classic Cold War monitoring to one that appropriately aligns with a wartime mission,” he said.

The Fleet ASW Warfare Command, as stated in Task Force ASW’s “ASW Concept of Operations” document, is focused on “compressing the detect-to-engage sequence by employing networked data, collaborative planning and rapid engagement to quickly destroy enemy forces.”

The long-term transformational strategy involves securing a maneuvering area rid of hostile submarines, and maintaining the ability to destroy submarines at will, at a time and place of choosing.

“The most important component of shortening the detect-to-engage timeline is tying the sensors to the shooters,” Toti said. “A critical and frequently overlooked aspect of that timeline is having shooters in the right place in the right time in order to react. It’s all about getting weapons on target and defeating the submarine.

“Sensors being networked in real time and reporting at the front end of this process are extremely important. The back end of this process still relies on individual platforms being in the right location to react rapidly to conduct the kill part of the chain.”

Having sensors off-board and placed in operationally appropriate areas would help a sea base, such as an expeditionary strike group, sanitize a chosen operating area, Toti said. Such systems as the Advanced Deployable System — a portable field of sensors spaced on the sea floor or suspended at various depths — are designed to provide a grid to rapidly detect and track an intruding submarine.

The “ASW Concept of Operations” envisions “pervasive awareness by way of hundreds, even thousands, of small sensing and computing devices that permeate the operating environment.” Such an autonomous sensor field could provide a highly detailed, precise picture of the underwater battlespace that would translate into precise targeting solutions and more rapid response to intruding submarines.

The Navy’s goal is to use FORCEnet to “integrate warriors, sensors, platforms, and weapons into a networked distributed combat force applicable across all levels of ASW,” according to the concept. FORCEnet is an operational concept that calls for the use of new information infrastructures to enhance the service’s capabilities to detect, target and attack enemy forces.

The sensor challenges are significant.

“The world of ASW is governed by physics, which often dictates solutions,” Toti said. “Passive technologies are becoming exponentially less effective. As submarine noise decreases by half, it becomes 10 times more difficult to detect. To a large extent we have to do detection by active means.”

Active sonar presents problems not envisioned until recent years. “We’re finding it increasingly difficult to investigate the most effective technologies because of marine mammal issues,” he said. “There is a small but measurable effect on marine life from using active sonar technology.

“We can improve sonar in an environmentally responsible manner,” he said. “It is a huge issue, one we’ve got to come to terms within our ability to develop sensors. Whales and active sonars can peacefully co-exist.”

Toti sees unmanned aerial and underwater vehicles as promising ASW platforms, but considers them to be long-term development issues, with solutions governed by developing breakthroughs to the barriers of physics. One needed advance is a reliable, timely, rapid mobile data link to communicate between underwater and aerial platforms and sensors.

“It takes time to develop such technologies,” he said. “People would love to force invention but that would mean a lot of money being poured into dry wells. We are fairly limited to what we have in force structure today for the near and mid term.”

The transformational goal, however, remains a shift from platform-intensive to sensor-rich operations, which in turn would foster more effective and efficient employment of weapons and platforms. The “ASW Concept of Operations” cites the example of submarines “that now host sensors and weapons in a single platform will, in the future, also serve as command-and-control and logistical support bases for off-ship sensors and kill vehicles.”

“Platforms like [the Littoral Combat Ship] and [the Multimission Maritime Aircraft] can be made very effective ASW platforms, if the right kind of investment is made in mission modules and systems,” Toti said. “It’s not the platform itself but the integrated mission architecture built into the platform that brings capability.”

In the near term, ASW weapons will be limited to improvements of current weapons modified with open architecture to accommodate rapid of upgrades. “The Mk54 lightweight torpedo [which incorporates guidance systems developed for the Mk48 submarine-launched torpedo into an air- or surface-fired torpedo] is a great step forward and shows a lot of promise,” Toti said. “We are just starting to field the weapon.”

There is still a role for low-tech ASW weapons in the littoral environment. In many cases, the water is clear enough to see a submarine submerged in the shallows from the air. Dumb depth bombs remain particularly effective against subs in shallow water.

While pushing ahead with transformation, Toti stresses that the Navy’s current ASW capabilities are impressive.

“Too many people have been downplaying our ASW capability and that sends the wrong message to our potential adversaries,” he said. “If a country thinks that procuring submarines is going to solve its American access problems, it’s wrong. We will prevail in an ASW world. The outcome won’t be any different whether the country has submarines or not.”

CORRECTION:

Adm. John B. Nathman’s title was listed incorrectly in this issue. He is commander of U.S. Fleet Forces Command.