ASW: Will We Ever Learn?

An antisubmarine warfare (ASW) campaign will be the opening phase of conflict in the western Pacific, one of the planet’s toughest acoustic environments. It will be a “come as you are” street fight against an adversary who may engage the United States in unanticipated ways. Does the U.S. Navy want to be surprised? Can it afford to wait? 

ASW has a history of surprises, and the lessons learned—again and again—rarely seem to stick. The litany begins with World War I as the U-boat demonstrated an unforeseen open-ocean capability. During World War II, U-boats again threatened Britain’s lifeline, and torpedoed tankers burned along Atlantic beaches. The postwar revelation of Germany’s Type XXI U-boat and the prospect of the Soviet Union building hundreds of copies made ASW an urgent national priority, while the Nautilus (SSN-571) forced a complete reassessment of U.S. capabilities.¹ The quiet Akula-class submarine was the last great shock of the Cold War.

Whether arising through hubris, apathy, or espionage, these surprises usually brought urgent responses, but rarely have the reactions translated to lasting redirection of resources to solutions.² Why? Because the ASW threat is acknowledged only in the abstract. The Navy never encountered the Type XXI in combat, nor anything analogous—in combat—since. 

There were, however, exceptions. Two major academic studies and the U.S. Cold War ASW organization, all remarkable for their broad-reaching and long-lasting effects, can and should be models to resurrect what once was a well-integrated cross-platform ASW “system of systems.”

The Lessons of History

World War I began with no real ASW, as the threat of the U-boat was unappreciated. The Allied realization that underwater detection would be key to success led to active sonar research on both sides of the Atlantic, but while British efforts continued postwar, U.S. efforts lapsed as strategists focused on a Pacific war, assuming little threat from Japanese submarines.³ This left the U.S. Navy woefully unprepared for World War II’s Battle of the Atlantic. In 1943, the need for centralized ASW coordination finally led to the creation of Tenth Fleet, introducing a top-level focus. 

The Navy also learned the value of academia. The Antisubmarine Warfare Operations Research Group developed mathematically based search, screening, and attack procedures, building a foundation for operations research and systems analysis that carried the Navy through the Cold War. Similarly, wartime work carried on under the auspices of the National Defense Research Committee and others would lead to a better understanding of the physics of sound in the ocean, and a decade later, to systems that could exploit it. 

While the Type XXI U-boat arrived too late to affect the Battle of the Atlantic, it demonstrated performance not exceeded until the advent of nuclear power a decade later. With a streamlined hull and the ability to maintain a submerged speed of 15 knots for two hours, the Type XXI could evade at speeds higher than a destroyer’s sonar could maintain contact, dramatically changing the nature of undersea warfare. Only misplaced priorities and immature engineering kept it from becoming a wartime game-changer. This knowledge, coupled with the lessons of the wartime Tenth Fleet, led to the realization that central management of ASW must continue, and in 1946 Chief of Naval Operations Chester W. Nimitz created the Coordinator of Undersea Warfare (OP-31).⁴ 

This office continued to evolve until 1964, when Vice Admiral Charles B. Martell was assigned as director of ASW Programs (OP-95). Key to the success of this new office was that it was “doubled-hatted” as the ASW Systems Project Office (PM-4), with authority to ensure cross-program and -platform warfighting balance, using the Strategic Systems Project Office model. The creation of OP-95 brought with it two important and previously nonexistent features of the Washington budget focus: OPNAV sponsorship of fixed surveillance systems like the sound surveillance system (SOSUS) and cross-platform coordinated ASW. At sea, hunter-killer groups, building on wartime lessons and now including supporting submarines, began developing tactics to defeat this new threat. It was here the Navy first learned the difficulty of integrated submarine operations: water- and air-space management is marginally effective, and “blue-on-blue,” particularly air-on-sub, remains a seemingly unsolvable problem.

In recognition of the wartime contributions of academia, the Navy instituted “summer studies,” inviting leading scholars to study problems of national interest. In 1950, Project Hartwell, a “short-term intensive assault on the technical barriers that now limit the effectiveness of anti-submarine and anti-mine warfare” was the first major effort.⁵ The study’s recommendations led to or validated efforts that included tactical nuclear weapons, helicopters with dipping sonar, the single hunter-killer aircraft that became the S-2, nonacoustic ASW, and, perhaps most critically, the technologies that enabled SOSUS. 

The second major study was Project Nobska, convened in 1956 as the revolutionary capabilities of the Nautilus fully entered the Navy’s consciousness. The panel’s report “presented a unique integrated picture of the ASW problem and its likely solutions” and “helped to mold Polaris.” Recommendations led to the MK 46 and MK 48 torpedoes; fast, deep-diving quiet submarines; supported low-frequency, active sonar; and rapid prototyping.⁶ 

Lower frequency sonars that could exploit the multipath characteristics of the acoustic environment enabled new strategies to counter the emergent Soviet threat. The quiet submarine became the ASW platform of choice, operating in forward barriers to forestall a third Battle of the Atlantic. Close partnerships with industry and academia were essential to evolve science into systems, as the Navy was in uncharted territory. 

A robust cross-platform revitalization of ASW soon followed with the introduction of passive narrowband signal processing, the P-3, and later the S-3 aircraft, with new sonobuoy inventories. Surface ships received towed arrays and the multipath-capable SQS-26/53 series sonars, as well as embarked helicopters to engage long-range contacts. These improvements allowed the U.S. Navy to impose its will on the Soviets through trail operations, acoustic and other intelligence collection, and interception of SOSUS-generated contacts. However, U.S. confidence quickly evaporated with the shock of the Akula.

Reaction was swift, thanks to a favorable budget climate, a solid research-and-development foundation, and a still-extant OP-95. Campaign analyses at the Naval War College and other centers, with the Maritime Strategy as a background, led to focused investment strategies. Reviews by the Defense Science Board, Naval Research Advisory Committee, and National Security Industrial Association asked hard questions and provided input based on years of experience.⁷ ASW master plans articulated the requirements and provided road maps for the cross-platform “system of systems” that makes ASW a unique team sport, while the Integrated ASW Assessment Team (“Team A”) monitored implementation. As the Cold War ended, the Navy was on the verge of significant new investments to counter the dramatically improving Soviet submarine force. Research-and-development efforts were poised to deliver low-frequency active sonars, both surveillance and tactical, deployable passive surveillance systems keyed to a quiet threat, a major update to the P-3 (paving the way to a new P-7), robust torpedo defense, and the Seawolf-class submarine. 

ASW Pays the Peace Dividend 

With the Soviet collapse, there was intense pressure to reap a peace dividend, and ASW priorities fell dramatically as adversary submarines went from threatening U.S. national security to posing a threat only to overseas national interests. Research and development, modernization, operations, and expertise all dwindled. The New London Laboratory, long the nation’s premier sonar research-and-development center, was downsized and consolidated at Newport. The contractor base atrophied as funding for exercises and analyses disappeared. The management and oversight that ensured investment balance crumbled, as OP-71, the successor to OP-95, closed its doors. The ASW master plan withered, and Team A was disbanded. The ability to articulate the requirement for cross-platform, integrated ASW, a relationship unique among warfare areas, has not been regained in the intervening quarter century.

Force levels were gutted: SSN-637 and many 688-class submarines were taken out of service well before the end of their service lives. The Seawolf program was truncated. Primary-mission ASW surface ships were decommissioned—again, many short of their expected life spans. The P-3 community was downsized, forward bases closed, and the S-3 relegated to fleet support. The Navy drastically reduced acoustic undersea surveillance, cutting investment in fixed, deployable, and mobile systems. The new paradigm gave the Navy a littoral combat ship with “mission modules,” begging the question of how the operators accompanying the ASW module, when installed, will maintain proficiency while sitting ashore. ASW cannot be plug-and-play: acoustic sensors arguably are the most challenging to operate, learning curves are steep, and skills are highly perishable. Limited submarine services and environmental restrictions constrain at-sea training, and the Navy has yet to develop trainers that accurately simulate the sea for active sonar engagements. 

The Hardest Lesson

The primary lesson from past experiences is that broad area, all-source surveillance is essential for the successful execution of coordinated ASW. Without cueing, offensive antisubmarine warfare becomes a needle in a haystack, reduced to point defense characterized by alarming false contact rates, high weapon expenditures, and negative mission impact.

Effective ASW always will be expensive, requiring major investment in platforms, sensors, and weapons. From national asset surveillance through terminal engagement, balance among competing priorities can be achieved only through a concomitant and comprehensive investment strategy executed by a focused and experienced coalition encompassing all communities, including those outside the Navy. Complex resource allocation decisions and command-and-control organizations cannot be resolved within Navy warfare community–based organizations. 

Beginning in 1964, OP-95/PM-4 was the resource sponsor and overall manager for the entire Navy ASW program, the single voice for ASW, and an effective organization for meeting requirements through control over budget development and execution. The well-documented successes of this organization brought Navy ASW to global preeminence within what became known as a “national ASW system.”⁸ Over time, with the dissolution of the Office of the Chief of Naval Materiel in 1985 and the loss of PM-4, followed by the disestablishment of OP-71 at the end of the Cold War, this warfare focus has been diluted through decentralization driven not by ASW issues, but by a desire to institute hierarchical accountability in the acquisition community. 

This problem was addressed in 2015 through the establishment of the Undersea Warfare Center in New London, reporting to Commander, Submarine Force, Atlantic. Presumably, this organization coordinates among warfare community sponsors and outside activities to ensure comprehensive cross-platform warfare coordination, interoperability, and balance. This might provide acquisition accountability, but is it adequate for the warfighter? 

If not, acquisition remains with naval warfare community sponsors and likely will result in continued community-focused investment with little improvement in coordinated all-source broad-area surveillance and cross-platform operability. At the deckplate level, the Navy demands commanding officers have a thorough understanding of their ships’ operations, weapon systems and engineering plant. The Navy should expect the same from the leaders of this complex warfare area. 

Rigorous operations analysis still is required to underpin strategic, tactical, and programmatic decisions. A budgetary misconception, even after the Cold War, holds that ASW programs can somehow be “prioritized,” then funded in order.⁹ While there can be no argument that the attack submarine program is “more important” than, say, the MK 54 torpedo, the “nth” submarine is clearly not, and only good analysis can develop, articulate, and defend the rationale behind these complex resource allocation decisions. 

The Navy Cannot Get Fooled Again

Time and again the Navy has disarmed ASW physically, programmatically, and intellectually. Why has this been allowed, and how can the Navy regain global ASW excellence? First, it must look to history to determine what worked and why. Hartwell and Nobksa are prime examples of how to focus academic talent on difficult questions of national importance. Today, we should be asking our scientists:

• Why don’t active systems “work,” and what is the effect on operator confidence? Physics (e.g., the convergence zone) says the signal is there. Are there solutions to the classification problem? 
• Is the Navy sure its torpedoes will work, and can it defend against opponent torpedoes?
• Are research-and-development programs adequately funded and properly balanced between reactions to today’s headlines and long-term investment, and is the Navy facilitating the best possible interactions between the fleet and the developers, labs, and contractors? 
• What has happened to research in the Arctic and in nonacoustic ASW?

For nearly 50 years, the Navy had strategies and effective cross-platform, cross-community management to defeat the Soviet submarine threat. As the service seeks to properly manage ASW, it should be asking civilian and uniformed leadership:

• Can a single-platform sponsor ensure the Navy will be able to conduct theater-level combined arms ASW in a multithreat, cyber-intensive environment, with strategies, underpinned by rigorous analyses, to address likely threat scenarios? 
• Would a Battle of the South China Sea be a classical battle-force engagement or an analog to the 1980s tanker war, but with attacks on container ships to disrupt U.S. “just-in-time” manufacturing and distribution economies?
• Can the Navy provide persistent detection and cueing (i.e., real-time all-source locating data) to the fleet, supported by comprehensive operational and technical intelligence, adapting security requirements to legitimate operational needs? 
• Are programs fully funded from advance development through in-service engineering and maintenance?
• Is the Navy training the way it will fight? 
• Does the Navy have enough torpedoes? What were the lessons from the Falklands War?
• Can the Navy conduct highly sensitive science and research in the modern academic environment? 
• How are the Navy’s ASW capabilities viewed by its adversaries?
• When will Congress again ask these same questions?¹⁰
• Submarines, their weapons, and their skills will continue to advance. Though there are rarely, if ever, silver bullets in ASW, the Navy still must ask, “What have we not thought of, and what should we be asking?” The final question, however, is, “Do we have the skills, resources, and confidence that we can defeat any submarine threat anywhere in the world?” If the answer is no, or maybe, then it must be fixed. If the answer is yes, can it be improved? 

History says the Navy cannot afford to get fooled. Again.