Compact Inflatable Structures for Submerged Payload Launch & Recovery
AREA(S): Ground/Sea Vehicles
PROGRAM: Virginia Class Submarines
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.
The U.S. Navy (USN) seeks to develop enabling technologies for the use of soft
inflatable structures as components to undersea payload launch and recovery
(L&R) systems. Inflatable structures using seawater as the inflation medium
are particularly attractive to the USN because of their ability to produce
large developable shapes possessing significant load-carrying capacities and
stiffness when inflated and for their ability to achieve smaller form factors
and volume reductions when deflated.
The current state of inflatable soft structures technologies can provide unique
solutions to many challenges limiting today’s Undersea Warfare (USW) launch and
recovery operations. Inflatable soft structures have been successfully
developed for DoD, NASA, industry, etc. and are generally categorized in the
• Inflatable control surfaces,
• Deployable energy absorbers,
• Temporary “on-demand” structures
Successful design and performance of soft inflatable structures is attributed
to technological advancements derived from:
• High Performance Fibers (HPF) including but not limited to Vectran®, DSP®
(dimensionally stable polyester), PEN (polyethylene napthalate), Spectra®
(ultra-high molecular weight polyethylene), Kevlar®, and others,
• Novel fabric architectures and 3-dimensional preforms capable of unique
• Continuous weaving processes for elimination of seams,
• Robust Physics-Based Modeling (PBM) methods with Fluid-Structure Interaction
• Material test methods for characterization of multi-axial mechanical behaviors
for inputs to numerical models.
Collectively, these advancements have established a sound technology base; one
that can be readily leveraged for innovative solutions to soft structure
designs requiring significant load-carrying capacities, shock mitigation,
dynamic energy absorption, rapid deployment, large deployed-to-stowed volume
ratios, and fail-safe modes of operations.
This effort seeks to develop a soft inflatable structure, with a compact and
predictable deflated shape, for payload recovery operations. The inflated and
deflated configurations will be compared to established deployed-to-stowed
volume ratios. The inflatable structures considered for use may include, but
are not limited to, control volumes constructed of inflated skins, membrane
bladders, coated fabrics, and hybrid (soft/rigid) material systems. Hybrid
structures may include inflatable elements with semi- or fully-rigid
reinforcements serving as deployment shaping controls. Seawater, supplied
through an integral pump, will be the inflation medium.
The key challenge to taking advantage of their space saving potentials is
managing the deflated shape and resulting form factor especially in the
presence of crossflow velocity fields. This challenge is increasingly
difficult for larger structures that are not accessible to personnel as the
inflated components are deflating. Payload L&R systems operating at
prescribed submergence depths require that the inflatable components function
in a deterministic, repeatable and predictable manner in the undersea
The minimum operational constraints are:
• Inflation media is seawater
• Submerged operational depth: 100 ft (inflating and deflating)
• Operational cycles: 1000
• Minimum size of inflatable features: 6” diameter x 36” length
• Assist vehicle recovery via submarine standard 21-inch diameter by 25-foot
• Crossflow velocity: 5 knots
• Inflate to full pressure in 15.0 seconds
• Maintain internal pressure for 24 hours
• Provide pressure relief for internal pressure exceeding 2.5x ambient pressure
within 5.0 seconds
• Variance in deflated volume envelope: < 10% over 1000 operational cycles
The volumes of the soft inflatable structures at the inflated and deflated
states will be determined through simulations, experiments and demonstrations.
The developable shapes upon reaching the inflation pressures will be predicted
through modeling simulations and measured from experiments. The deflated shapes
and form factors will be predicted through modeling simulations and measured
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
project as set forth by DSS and ONR 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 advanced
phases of this contract.
Proposers must provide concept designs, simulations of initial prototype
designs, test results from laboratory experiments, and other relevant
documentation to demonstrate that the proposed technical solutions are feasible
for accomplishing the stated objectives and will meet the performance
parameters set forth in the description.
By submitting Phase I proof of feasibility documentation, the small business
asserts that none of the funding for the cited technology was reimbursed under
any federal government agency’s SBIR/STTR program. Demonstrating proof of
feasibility is a requirement for a Direct to Phase II award.
PHASE II: For
this topic, proposers must meet the following program requirements for each
round to be considered for the next round:
Round I: Select and optimize a soft inflatable structure including material
selections, hydraulic layout design and manifolding (as required),
inflation/deflation sequencing, hard-to-soft-goods connections for vehicle
recovery from a notional launch tube. As stated in the solicitation, the period
of performance for Round I shall not exceed 6 months and the total fixed price
shall not exceed $250,000.
Round II: Identify operational, safety and environmental issues of proposed
designs and will perform risk identifications, risk assessments and risk
mitigation plans during the concept development stage. As stated in the
solicitation, the period of performance for Round II shall not exceed 6 months
and the total fixed price shall not exceed $500,000.
Round III: Prototype build of the proposed soft inflatable structure and
testing to validate achievement of the deflation objectives stated in the
description. The prototype soft inflatable structure including deflation
capability shall be delivered to the US Navy for testing in accordance with the
operational requirements stated. As stated in the solicitation, the period of
performance for Round III shall not exceed 6 months and the total fixed price
shall not exceed $750,000.
It is probable that the work under this effort will be classified under Phase
II (see Description section for details).
DUAL USE APPLICATIONS: Round IV: Installation of a final Prototype system into
a submarine horizontal torpedo tube for operational test and evaluation for
vehicle recovery. This Round may result in a limited number of licenses of the
technology to allow for testing of the technology in various conditions and by
multiple end users. The resulting technology will be of significant interest to
the oil, power and telecommunications industries which rely on UUVs for
monitoring and exploration of pipelines and cables on the seabed. Subsurface vehicle
recovery would be a significant benefit.
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Undersea Payloads; Launch and Recovery Systems; Soft Structures; Inflatables