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This second Installment of the discussion of the SSBN Security Program describes the projects which comprise the program to convey the breadth and depth of the research directed toward understanding potential pre-launch vulnerabilities of the SSBN force. It touches briefly on the spin-off SSBN Survivability and SSN Security Programs.

Mr. Ravnus has spent 35 years in SLBM and SSBN test, evaluation and assessment. He began his career at the Johns Hopkins University/Applied Physics Laboratory where he performed SSBN assessments. He was also technical advisor to COMSUBLANT and CINCLANT. He is a plank owner in the SSBN Security Program and contributed to establishing its philosophy, objectives and management plan.

Mr. Ravnus continues to contribute to the SSBN Security Program as an independent consultant to JHU/APL.

Elements of the Program

The 1968 Foster Memorandum referred to in the previous article [Editor’s Note: See the April 1996 Issue of THE SUBMARINE REVIEW, p. 25] stimulated the Navy to formulate and implement the SSBN Security Program. Initially the program was named the SSBN Defense Program because an SSBN Survivability program as suggested in the memorandum bad a specific connotation in the PPBS. That is, survivability referred to the ability of a platform or weapon system to survive hostile engagements and continue to perform. The Navy did not want a program that aimed solely at the SSBN’s ability to survive engagements, but rather one that maintained and enhanced the at-sea SSBN’s ability to avoid engagements by its immunity to detection. Some Navy officials believed Defense also created the wrong impression so the program was eventually named the SSBN Security Program with the principal objective of maintaining the covert mobility of SSBNs

While many familiar with SSBN security think of the program as the research and advanced technology development efforts of the SSBN Security Technology Program, the Navy, in fact, created a comprehensive set of programs to address SSBN security issues. The SSBN Security Program included: The SSBN Security Technology Program (SSTP), The SSBN Tactical Development Program (STOP), an all-source intelligence program, and a series of countermeasure development and deployment programs. Later, in 1986, as the potential of various detection technologies was thoroughly understood, the SSBN Survivability Program was created to develop and demonstrate countermeasure technology deemed prudent to have available if ever needed. Each of these projects contributed to comprehensive understanding and mitigation of potential vulnerabilities of SSBNs both near and far term. The countermeasures developed and deployed remain classified and therefore are not discussed herein.

The SSBN Security Technology Program

Because the Dr. Foster Memorandum established the charter and provided guidance to the Navy on program execution of the SSTP it is reproduced here in its entirety.

16 October 1968


SUBJECT: SSBN Survivability

In view of the Soviet buildup of submarine capability in terms of both quantity and advancing technology, I believe it prudent to take those actions which will ensure the continuing survivability of our SSBN force well into the future. Toward this end, I am considering formulation of a separate and new line item in the FY 70 R&D budget on SSBN survivability. The basic objective of such an endeavor would be to develop all relevant technologies, on a continuing basis, to ensure the long term survivability of the present FBM force as well as providing the technological base for any future sea-based systems such as ULMS. (Editor’s note: ULMS, the Undersea Launched Missile System was the 1968 SIRAT-X Study proposal/or the next generation strategic weapon system. ULMS became the Trident system.)

My rationale for considering a separate line item, as opposed to doing the work as part of the ASW efforts, is generally as follows. Although the technologies involved are admittedly similar, I believe that if the same people were working both the offense and defense problems there might be a tendency to gravitate to one position to the detriment of the other.

With SSBN survivability a separate line item, pursued in part by different personnel than ASW, the competition that would naturally evolve should bring forth the best efforts in both activities.

Relative to the potential SSBN survivability line item, I would like to have your views on the subject, including a list of specific tasks that you believe should be pursued in such an activity. It is preferable that such a listing not be prioritized. After my review of these specific tasks, I would then like to get together with you to mutually establish the substance and priorities for such a program. The potential problem that you outlined in your note can be addressed at that time as can the nomenclature for a new line item.

John S. Foster, Jr.

After several iterations on program content and priorities the SSBN Security Technology Program was initiated in FY 70. The specific guidance on program execution resulted in the Navy assigning the program to the Strategic Systems Project Office (SSPO), and SSPO selecting the Johns Hopkins University/ Applied Physics Laboratory (JHU/APL) as the prime contractor. Both of these organizations were selected because of their reputations for technical excellence, their demonstrated ability to manage large and complex technical programs, their intimate knowledge of the technical and operational details of the FBM program, and their lack of any previous ASW research work (DDR&E demanded a fresh look at the problem). In 1983 Navy program management was shifted to the Office of the Chief of Naval Operations, where it is administered within the Security and Technology Branch of the Submarine Warfare Directorate (OPNAV N875). While JHU/APL remains the principal contractor, an original program policy of obtaining the best talent available to pursue the research projects, whether from industry, academia, Navy laboratories or national laboratories remains in effect.

The SSBN Security Technology Program was formulated as a non-acquisition R&D program with the objectives of: (1) developing understanding of operational techniques and potentially exploitable physical phenomena associated with SSBN operations that would permit accurate assessment of any potential threat to the FBM force and, (2) developing techniques, countermeasures, and advanced technology that would ensure the survivability of the force against such threats. Thus the program is logically com- prised of two major activities, force security assessment and technology research and development. The technology research and development activity is physics based, that is its objective is to understand the limits on the ASW utility of any submarine observable phenomenon imposed by the laws of physics, not those imposed by current technology limitations. Neither is the program driven by intelligence information. Intelligence, however, does provide an additional input for project selection and prioritization. The force security assessment project evaluates the implications of advanced technology (both detection and countermeasure technology) as well as current threats. The top-level assessment results were discussed in the previous SUBMARINE REVIEW article SSBN Security so the discussion here will concentrate on the technology research element.

Although the detailed organization of the program has varied over the years as the major thrusts changed, the program through-out its history has maintained a three element division for planning and execution. Those elements are, Acoustic Technology, Non-acoustic Technology and Operations Security. The Operations Security element includes the force security assessment activity as well as technical assistance to fleet SSBN security projects such as the STDP, the Port Egress Task Force and the SSBN Continuity of Operations Project (SCOOP).

The program philosophy is to systematically explore all submarine-generated phenomena and the potential exploitability of those phenomena over the entire range of submarine operating conditions and the environments in which they operate. No investigation of a promising technology is considered to be complete until it is demonstrated full-scale, at sea. To that end, the program developed a structured process for selection and pursuit of specific research projects. That process is a series of tasks that collectively constitute a research activity, start to finish. Those tasks are:

  • Phenomenology Description
  • Concept Development – Hypotheses
  • Sensor Development – Laboratory/Field Tests
  • Signal Model – Data Collection and Analysis
  • Noise Model – Data Collection and Analysis
  • Detection Algorithms – Signal Processing
  • At-Sea Tests – Plan/Execute/ Analyze
  • Performance Prediction – Probability of Detection/False Alarm Rate
  • Operating Characteristics – Environment/Depth/Speed/Habits/Tactics
  • Countermeasure Concepts – Tactics/System Hardware Development
  • Fleet Guidance/Tactical Exercises/Naval Material Development

The process ensures thorough and rigorous examination of each technology selected and provides necessary off-ramps as the activity proceeds. As anyone who has attempted to probe the oceans secrets knows, the ocean does not give them up easily. So some of the SSTP research activities have had a life span 10 years or more, encompassing a series of major at-sea experiments. Therefore, the single purpose, stable management and stable funding the SSBN Security Technology Program has experienced have been absolutely essential ingredients to program success. Because of the cost of at-sea experiments and the complexity of the experimental sensors and data acquisition systems involved, pursuit of joint research projects with SPAWAR, NAVSEA, ARPA and Navy Labs has been an equally important contributor to success. In the course of the program it has employed the services of over 150 industrial contractors, universities and laboratories, taking advantage of their specialized expertise.

The easiest way to describe the nature of the research activities of the program over the past 26 years is to present a list of program accomplishments. While many of the program research results remain classified, the following unclassified list amply conveys the scope of activity and the return the nation has received on the SSTP research investment.


Passive Acoustics
Steady State Detection

First to develop and demonstrate FFT technology for real-time multi-channel beamforming and signal processing.

Developed and demonstrated techniques for measuring and compensating for long towed array deviations from straightness.

Measured in-situ signal coherence across a very long towed array. Results showed achievable gains significantly greater than bad been predicted.

Demonstrated that by capitalizing on low frequency ambient noise anisotropy substantial gains over conventional array gain could be achieved.

First evaluation of submarine detectability in the 0.01 to 1 Hz frequency region.

Transient Detection

Quantified detectability of SSBN specific transient evolutions. First demonstrated the potential for automated transient detection at low false alarm rates.

Acoustic Signatures

Determined physical mechanisms responsible for hull SWATHs. Developed a physical explanation for the low frequency shaft related noise (LFSRN) phenomenon.

Active Acoustics

Low Frequency

First tests of very long range, low frequency active acoustics. Developed explosive source technology used in target strength measurement.

Conducted first full scale measurements of low frequency target strength.

Conducted first tests of low frequency active barrier concepts.
Conducted first tests of low frequency active in shallow water.
Developed first low frequency active intercept receiver.
Developed first tactical decision aid for low frequency acoustics.
First demonstration of low frequency active bistatic receiver.

High Frequency

Designed an advanced technology high frequency, high resolution trailing sonar for countermeasure evaluation and assessment.

Developed active sonar detection avoidance, evasion and break trail tactics.


Mast Detection

Developed first validated models of radar mast detection. Demonstrated in-situ radar detectability of submarine periscopes and masts.

Floating Wire Detection

Quantified radar detectability of floating wire antenna which led to changes in the operational utilization of the antenna.

Developed radar intercept receiver wholly contained within the floating wire.


Employed theoretical studies, tow tank experiments and in-situ full scale experiments to develop submarine induced hydrodynamic signature generation, propagation, and decay models.

Validated the models with in-situ full scale experimental data.

Quantified detectability of submarine hydrodynamic wake.

Employed submarine ejected dye trails to quantify potential of submarine wake trailing.

Performed first two-dimensional high resolution measurements of ocean microstructure.



Conducted first scientific mapping of geologic noise spectra using aircraft.

Conducted first flight demonstration of superconducting magnetometer.

Performed first in-air measurements of ELFE signature.

Conducted first active magnetohydrodynamics experiments.


Developed and conducted first tests with fixed electromagnetic barrier sensors.

Demonstrated significant noise cancellation possible using fixed sensors.


Conducted first DC and AC electromagnetic signature measurements on fully submerged submarines with fixed high sensitivity sensors.

Demonstrated technical feasibility of reducing submarine MAD signatures through closed loop degaussing.


Developed first millidegree sensitivity, absolute temperature, scanning, airborne radiometer.

Identified previously observed IR submarine scars as manifestations of the sail plane vortex wake.

Demonstrated that submarine induced internal waves do not produce detectable IR signatures.



Developed first low light level imaging system for bioluminescence detection.

Developed first quantified bioluminescence detection model.

Developed self-monitoring countermeasure system for bioluminescence.

Conducted investigation of optical detectability of communications buoy.

Developed communications buoy optical detection countermeasure.


Developed first airborne digital lidar system.

Demonstrated potential of lidar for hull detection.

Developed quantified detection model for submarine hull.

Developed and demonstrated submarine hull mounted lidar intercept receiver.


First use of AXBT sensors deployed in fields to determine the three dimensional characteristics of the ocean environment.

Program was a leader in quantifying the importance of ocean environmental measurements to acoustic and non-acoustic detection concepts resulting in:

Establishment of SSBN Security Program Environmental Data Base, a large collection of raw and averaged acoustic and non-acoustic environmental data unique in its variety and world wide distribution.

Developed a methodology for specification of environmental measurements requirements. Used to provide specific direction to NAVOCEANO for use in designing surveys.

Developed detailed Strategic Area Notebooks which provide a unique global assessment of submarine detectability based on environmental data in each of the SSBN patrol areas.

Developed techniques and published guidance for tactical utilization of oceanography.

Tactical Decision Aids

Developed the first tactical decision aid for topographic noise stripping on a PC.

Initiated the first development of an expert system tactical decision aid for submarines which was subsequently transitioned to the ARPA Signature Management Program.

Developed and demonstrated the capability to directly receive and display satellite imagery of environmental parameters on the Navy desktop computer.

Developed the first tactical decision aid for low frequency active acoustics.

In addition to the tangible results listed, the SSTP has become the Navy leadership resource in submarine stealth technology, ASW science and technology, and full-scale, at-sea experiment design and execution. It is the Navy’s storehouse of knowledge and data in all submarine detectability phenomena, ocean environment characterization, and SSBN operations and habits characterization. And, it has developed and maintains assessment models for all plausible anti SSBN ASW employment tactics including, open ocean search, trail from port, surveillance assisted search, area bombardment and tagging.

The SSTP continues its research activities today albeit with substantially reduced funding.

The SSBN Tactics Development Project

At the time the SSTP was being structured, the Chief of Naval Operations was concerned about the security of the SSBN force from an operational standpoint. Based on the facts that the Soviet submarine force was improving at a rapid rate and that any advanced technology developed would not reach the fleet for 5 to 10 years, the CNO directed COMSUBLANT and COMSUBPAC to establish an SSBN Tactical Development Program. In order to insure that the SSTP and STDP were coordinated, SSPO was directed to provide funding and technical support to the STDP and to establish direct liaison with the Force Commanders.

The STDP was managed by the Force Commanders until 1980 when management was transferred to Commander, Submarine Development Squadron TWELVE. Sonalysts has been, and remains the principal support contractor to the STDP. The program employs analysis, simulation, gaming and exercises to develop SSBN security related tactics and to ensure SSBN operational security. The STDP developed the SSBN Security Manual which ultimately was incorporated in the NWP series.

SSBN tactics were developed and published for contact avoidance, evasion, break-trail, countermeasure employment, port egress, transient signature and other patrol habits management, and guidance was promulgated for control of SSBN maneuver induced observables. Just as in the projects of the SSTP, the tactics development projects are not considered complete until they are demonstrated and refined in at-sea exercises. Thus a major element of the STDP is the Security Exercise Project or SECEX.

The SECEX project is comprised of three types of exercises: Tactical SECEXs, Scientific SECEXs and Forward Area SECEXs. Tactical SECEXs are those employed to demonstrate and refine the specific tactics developed by the STDP. Scientific SECEXs are joint efforts with the SSTP to demonstrate and evaluate the advanced technology developed by the SSTP in a tactical environment. Forward area SECEXs are employed on a random basis in statistically significant numbers to confirm the security of SSBNs on patrol.

The STDP contributed to and conducted joint exercises with the Port Egress Task Force and the SCOOP Task Force. The program has annual multi-day performance review and planning sessions that are chaired by the Force Commanders’ staff and include Development Squadron TWELVE commander and staff, Submarine Groups NINE and TEN staff, SSTP staff, SSP staff, CINCSTRAT staff and appropriate contractors. The STDP continues today, also with reduced funding and therefore reduced level of activity.

The All-Source Intelligence Program

Coincident with the formulation of the STDP, the Naval Intelligence Command was tasked to create an SSBN Security intelligence assessment program. The program was highly classified and access was strictly limited, with a specific need-to-know basis. The program employed all sources of intelligence data to determine and evaluate any Soviet reaction to SSBN operations. Special focus was placed on Soviet submarine, MPA,AGI and AGOR activities. Each SSBN patrol track was reconstructed and searched for coincidence with any Soviet platform. Any even remotely possible coincidence was researched in great detail and an assessment was made and reported to the VCNO, the Director of Submarine Warfare, the Director of SSPO and the Program Manager and Technical Director of the SSTP. The program discovered attempts of Soviet anti-SSBN operations but uncovered no Soviet successes throughout the duration of the Cold War. With the collapse of the Soviet Union the program was terminated.

SSBN Survivability Program

The SSBN Survivability Program is a non-acquisition program with the objective to identify and develop prototype technology to enhance SSBN survivability in a hostile environment. It selects from the SSBN Security Program (or elsewhere) countermeasure concepts for prototype technology development and demonstration. The countermeasure concept selection process is keyed to the assessments performed in the SSBN Security program. Priority therefore is established by the assessed severity of potential threat and an estimate of the time required by an adversary to field such a threat. The countermeasure concept feasibility is demonstrated at sea employing the prototype technology and, when successful, the requisite documentation for transition to full scale engineering development is prepared.

SSN Security Program

The end of the Cold War brought a dramatic change in emphasis in SSN missions and with that change a requirement to reassess potential SSN vulnerabilities. The emphasis on operations in the littoral in support of the land battle increased the importance of understanding the potential vulnerability of SSNs to short range, shallow water detection systems. Since the SSBN Security Technology and Survivability Programs bad developed knowledge and a technology base for all potential submarine observables, the Navy decided to establish a specific effort to apply those to assessment of SSNs in the new missions context. The SSN Security Program was therefore established in 1991 with a charter and approach similar to the SSBN program and employing the same technical management and performing organizations. The SSN Security Program is able to perform assessments with a relatively low level of funding only because of its leveraging off the SSBN Security Technology and Survivability Programs.


When the Assured Destruction deterrence policy elevated the importance of prelaunch survivability of strategic weapons systems, the Navy responded with a comprehensive program to ensure that characteristic of the SLBM force as well as to ensure the confidence our national security decision makers had in that characteristic of the SLBM force. Prelaunch survivability of SSBNs was considered so important to our nation’s deterrent posture that the Defense Science Board, the JASONS, the Central Intelligence Agency and the Office of the Secretary of Defense were tasked at various times during the last 25 years to independently evaluate aspects of SSBN security. To the credit of the Navy’s SSBN Security Program, none of its conclusions were ever refuted by those independent assessments. The net assessment remains that our SLBM force is secure now and into the foreseeable future. That assessment is made confidently because of the technical and tactical enhancements deployed and the thorough and rigorous investigations of all potential ASW technologies conducted by the SSBN Security Program.


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