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Retractable Mooring Fixture


OBJECTIVE: Through the application of advanced material(s) and manufacturing processes, develop a mooring fixture to replace the existing bitt and/or chock configuration onboard naval surface ships. DESCRIPTION: Presently, both the naval and commercial industry use carbon steel bitts and chocks to properly tie-up or moor a ship (Ref 2 and 3). For DDG 51 Class ships, those bitts and chocks, which are located on the flight deck, are limited in their allowable height above the deck by specifications pertaining to helicopter operations. As a result, they are recessed into the deck itself. Raising and lowering the bitts and chocks are manual operations requiring as many as four individuals (due to the weight of the assemblies in excess of 270 lbs) and also require the use of specialized tools. Once raised, both are locked in the"up"position. For the bitt assembly, there is a rubber gasket seal at the deck opening which fits tight to the bitt barrel for the purpose of preventing water from reaching the decks below. Both have either 2-inch or 4-inch drain lines to facilitate water exiting the pockets in which the fixtures are stowed. Naval flight decks are a highly corrosive environment, and corrosion rapidly affects the operation of these mooring fixtures due to their weight, tight tolerances and method of operation. Bitt and chock assembly corrosion and the subsequent degradation of system performance are top recurring issues for DDG CLASSRON. The effort to reduce manning has forced prioritization with regards to maintenance and the attention the crew is able to pay to these mooring fixtures often suffers as a result. Limited personnel and the flight deck"s highly corrosive environment present a recurring and costly maintenance challenge. System failure results in a reduced mooring capability, increased maintenance time and frequency, and as a result, increased life-cycle costs. This topic seeks to explore innovative approaches to resolve a long-standing, life-cycle management issue for DDG 51 Class ships. Proposers are encouraged to explore alternative design solutions, manufacturing processes and/or material systems with robust mechanical properties to withstand the harsh operating environment seen by these mooring fixtures on a daily basis. Proposers are also encouraged to explore solutions that provide a combined (bitt and chock) functionality to deliver equivalent performance within the footprint of the allotted space onboard ships (Ref 1). Proposers will need to be mindful of the requirement to provide a solution that can be recessed within the storage pocket of the deck and should address the ability to be sealed to prevent water intrusion into adjacent spaces. Proposed concepts should be simple to maintain and operate. Material systems proposed should not be predisposed to galvanic corrosion. In addition, proposers should address the method of deployment and locking, with the use of minimal manpower. Meeting the need for reduced maintenance and increased operational reliability and maintainability in a maritime environment represents the most significant challenge associated with a bitt and chock replacement design solution. PHASE I: Demonstrate the feasibility of a replacement retractable mooring fixture and its ability to reliably operate in the presence of corrosion. Proposers should identify suitable configurations, candidate materials, equipment, manufacturing processes and methods of installation anticipated to enable the development and integration of the proposed system. Establish performance goals and metrics to analyze the viability of the proposed solution. The small business will provide a Phase II development plan as well as a test and evaluation plan with performance goals and key technical milestones to be utilized to verify performance and suitability. PHASE II: Develop, demonstrate and fabricate a prototype as identified in Phase I. In a laboratory environment, demonstrate that the prototype system meets the performance goals established in Phase I. The prototype will be evaluated to determine its capability in meeting the performance goals defined in Phase II development and respective test and evaluation plans. Provide a detailed Phase III plan for certification, validation, and method of implementation into a future ship test and/or design environment. Prepare cost estimates, logistics data packages, and interface documents for use in both forward fit and retrofit ship programs. Develop a cost benefit analysis for Total Ownership Cost. PHASE III: Based upon the results of Phase II, the company will be expected to construct a prototype for testing in a naval shipboard environment. Working with government and industry, install onboard a selected DDG 51 class hull and conduct extended shipboard testing. The company will support the Navy in an effort to install any necessary components required to allow for use of this technology in an extended shipboard testing operational environment. PRIVATE SECTOR COMMERCIAL POTENTIAL/DUAL-USE APPLICATIONS: Bitt and chock fixtures are widely used onboard commercial vessels. As such, corrosion, maintenance and general performance associated with bitts and chocks are not problems unique to the Navy. Additionally, commercial vessels operating helicopters or with similar height-above-the-deck restrictions have the potential to need a reliable retractable mooring fixture alternative as a means of removing possible obstructions from flight height-restricted spaces.
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