TECHNOLOGY AREA(S): Battlespace, Electronics, Sensors

ACQUISITION PROGRAM: PMS 415, Undersea Defensive Warfare Systems Program Office

The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR), 22 CFR Parts 120-130, which controls the export and import of defense-related material and services, including export of sensitive technical data, or the Export Administration Regulation (EAR), 15 CFR Parts 730-774, which controls dual use items. Offerors must disclose any proposed use of foreign nationals (FNs), their country(ies) of origin, the type of visa or work permit possessed, and the statement of work (SOW) tasks intended for accomplishment by the FN(s) in accordance with section 3.5 of the Announcement. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws.

OBJECTIVE: Develop an efficient depth control mechanism capable of being implemented into both existing and future 3-inch diameter Acoustic Device Countermeasures (ADC) to allow for increased amount of power for improved (i.e., greater source level and/or longer duration) acoustic performance.

DESCRIPTION: Current 3-inch Mk 2 devices utilize an electric motor and a small-ducted propeller for depth control to ascend from maximum submarine operational depths, or to descend from shallow submarine operational depths, or to maintain depth at the time of submarine launch. The motor runs off the existing Eagle-Picher lithium aluminum/iron disulfide (LiAl/FeS2) thermal battery (EAP-12189), which also provides power to the acoustics of the device. Improved acoustic performance in terms of increased duration and increased acoustic sound pressure levels is needed to counter ever-improving adversarial torpedoes. Reducing, or eliminating, the need for the depth control system to require power from the battery would leave increased power for enhancement of the acoustic output or duration of the device. Available power for the depth control varies depending on the launch depth and the acoustic mode. The technical challenge in designing the depth control system (selectable for Deep, Shallow and Launch Depth settings) is fitting it within the existing volume of approximately 70 inch squared and making it robust enough to survive and operate following exposure to accelerations and forces experienced by the device when it gets launched out of the internal countermeasure launcher aboard all current U.S. Navy submarines, at potentially all submarine operational depths. The maximum Peak Device Acceleration (G’s) that could be encountered is approximately ½ SINE Wave 120 g’s for 30 ms, and the maximum Hull Exit Velocity is 105 fps. By fitting it into the existing volume and surviving launch transients, the system could be utilized for both current and future devices.

As part of the effort, state-of-the-art in packaging and buoyancy compensation systems should be incorporated, potentially including high-pressure canister inflation and/or high-strength bladder materials. A redesigned depth control system has the potential to reduce the overall device cost by eliminating the need for the current specialized electric motor and ducted propeller. Physical dimensions of the current device include the following: weight in air 9.002 lbs.; buoyancy -0.853 lbs.; center of buoyancy 18.175 inches forward of tail; and center of gravity 22.311 inches forward of tail.

The Phase II effort will likely require secure access, and NAVSEA will process the DD254 to support the contractor for personnel and facility certification for secure access. The Phase I effort will not require access to classified information. If need be, data of the same level of complexity as secured data will be provided to support Phase I work.

Work produced in Phase II will likely become classified. Note: The prospective contractor(s) must be U.S. Owned and Operated with no Foreign Influence as defined by DoD 5220.22-M, National Industrial Security Program Operating Manual, unless acceptable mitigating procedures can and have been be implemented and approved by the Defense Security Service (DSS). The selected contractor and/or subcontractor must be able to acquire and maintain a secret level facility and Personnel Security Clearances, in order to perform on advanced phases of this contract as set forth by DSS and NAVSEA in order to gain access to classified information pertaining to the national defense of the United States and its allies; this will be an inherent requirement. The selected company will be required to safeguard classified material IAW DoD 5220.22-M during the advance phases of this contract.”

PHASE I: Provide a conceptual design of a depth control system including the dimensions, power source, and buoyancy calculations substantiating that the system can provide the depth control needed for the device, which includes providing buoyancy for a controlled ascent from submarine launch depths, providing negative buoyancy for a control descent from shallow launch depths, and providing the ability to maintain depth at the time of launch. Demonstrate the feasibility of the concept through modeling and simulation. Develop a Phase II plan. The Phase I Option, if exercised, will include the initial layout and capabilities description to build the prototype in Phase II.

PHASE II: Develop and deliver a prototype system for testing and evaluation based on the buoyancy-specific unclassified requirements stated in the current ADC Mk 2 performance specification for depth control, which can be appropriately provided to awardees. Perform evaluations that include acoustic testing and evaluation, both before and after mock launches from the internal countermeasure launcher facility maintained by the Naval Undersea Warfare Center in Newport, Rhode Island.  Provide, for final testing and certification, 3-5 prototypes as deliverables. Perform acoustic testing that will provide confidence that the depth control design does not affect the acoustic directivity patterns.

It is probable that the work under this effort will be classified under Phase II (see Description section for details).

PHASE III DUAL USE APPLICATIONS: Support the Navy in transitioning the technology to Navy use, which is expected to be in the form of engineering support for full environmental testing during Phase III, which could include storage temperature thermal cycling, lightweight shock testing, vibration analysis, additional acoustic evaluation testing, and full depth excursion testing. Ultimately, within Phase III, it is desired that at least two to three prototypes will be launched from a U.S. Navy submarine to assist in the full circle environmental evaluation of the design.

An example of a dual-use commercial application would be the launch of environmental measurement devices utilizing the efficient depth control system from Autonomous Undersea Vehicles (AUVs), or ships of opportunity, given the volume optimization of the launch mechanism.

REFERENCES:

1. Kundu, Pijush K.  Fluid Mechanics.  New York: Academic, 2002; https://www.elsevier.com/books/fluid-mechanics/kundu/978-0-08-054558-5

2. Burdic, William S.  Underwater Acoustic System Analysis.  Englewood Cliffs, New Jersey: Prentice Hall, 1991; http://www.worldcat.org/title/underwater-acoustic-system-analysis/oclc/551483500.

KEYWORDS: Acoustic Device Countermeasure; Center of Buoyancy; Center of Gravity; Depth Control; Internal Countermeasure Launcher; Buoyancy Control Methodologies