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Decompression of Atmosphere Onboard Distressed Submarine



OBJECTIVE: Develop a means to reduce the internal atmospheric pressure of a Distressed Submarine (DISSUB) without the need for ship’s electrical power. 

DESCRIPTION: The Navy has a safety requirement to provide the capability for the escape and rescue of crewmembers in the event of a DISSUB situation. A method to bring DISSUB internal atmosphere to 1 atm would significantly increase the chance of survival by crewmembers. There is currently no means for a DISSUB to lower its internal atmospheric pressure. Research and development (R&D) is needed, as there is no known commercial technology available technology that would fit the Navy’s requirements. There is a high probability that a Distressed Submarine (DISSUB) that ends up on the ocean bottom with all or some crewmembers alive, will have an internal atmosphere pressurized above 1 atm. This can be due to a number of reasons, such as flooding compressing the air in a compartment to a smaller volume, damage to high-pressure air banks/piping causing them to vent into a compartment, and crew use of Emergency Air Breathing system to fight casualties. A high internal atmospheric pressure can cause significant problems such as nitrogen narcosis, oxygen toxicity, and decompression sickness. Develop a prototype device that can lower the internal atmospheric pressure of a DISSUB by at least 1 atm, with a goal of lowering the pressure from 5 atm to 1 atm. The prototype device cannot require the availability of shipboard electrical power as power may not be available. The prototype device may rely on the stored energy of the ship’s high-pressure air banks, seawater pressure, or self-contained battery power. It must not require more than four people to operate or require significant operator physical exertion. Decompression must happen at a safe rate to prevent decompression sickness of crewmembers. Work produced in Phase II may 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 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: Define and develop a concept for reducing the internal atmospheric pressure of a DISSUB as outlined in the description. Demonstrate the feasibility of the concept by performing modeling and simulation to approximate the performance. The Phase I Option, if awarded, will include the initial design specifications and capabilities description to build a prototype solution in Phase II. Develop a Phase II plan. 

PHASE II: Based on the results of Phase I and the Phase II efforts, fabricate, validate, and deliver a prototype device capable of test demonstration in a simulated DISSUB environment. Provide a detailed test plan to demonstrate the deliverable meets the intent of program requirements. A Phase III qualification and transition plan will also be provided at the end of Phase II. It is probable that the work under this effort will be classified under Phase II (see Description section for details). 

PHASE III: Support the Navy in transitioning the technology to Navy use. Deliver the Phase II-developed prototype in a form factor and configuration that is ready for temporary installation onboard a Navy submarine. Participate in shipboard testing to prove functionality in an operational environment. This technology could be used by commercial manned submersibles and underwater research facilities. Additionally, this technology could be sold to other countries for use onboard their submarines. 


1: Harabin, A.L. "An analysis of decrements in vital capacity as an index of pulmonary oxygen toxicity." Journal of Applied Physiology 63(3), 1 Sept 1987: 1130-1135.

2:  Demchenko, Ivan. "Similar but not the same: normobaric and hyperbaric pulmonary oxygen toxicity, the role of nitric oxide." American Journal of Physiology (Lung and Cellular Molecular Physiology) 293, 9 July 2007: L229-L238.

KEYWORDS: Submarine Escape; Pressure Reduction; DISSUB; High Pressure Survival; Low Power Emergency On Submarines; Oxygen Toxicity 


Joshua Peters 

(202) 781-3542 

Stephanie Mohundro 

(202) 781-1425 

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