Near-term Mine Reconnaissance System [NMRS]
The Near-term Mine Reconnaissance System [NMRS] is being installed on various platforms, including the SSN-688 Los Angeles atttack submarines. The NMRS is a fibre-optic controlled vehicle which is equipped with a side scan sonar, designation AN/AQS-14. The launch and recovery of the reconnaissance vehicle is via a torpedo tube.
NMRS provides Theater Commanders with a near-term capability for conducting
clandestine minefield reconnaissance from a submarine. The UUV transits to an area to
determine if littoral waters are seeded with mines, allowing theater commander to rapidly assess probability of mines in the area; Highly accurate survey -- precisely locates and classifies mine-like objects, provides theater commander with detailed information used to estimate location of enemy-deployed mine defenses, unmined coastal areas and the need for further UUV sortie operations.
Enemy mining activity can severely hinder the US Navy's efforts to effectively control
the seas. As the Navy shifts its focus from a global threat to a focus on regional
challenges, we must focus on developing the capabilities needed to execute successful
operations in the complex "littoral environment". There is a need for cost-effective,
unmanned, clandestine, undersea, off-board sensors that can serve in a wide variety of
roles and missions, including mine warfare, surveillance, reconnaissance and intelligence
collection and tactical oceanography. To achieve this priority, the Navy has been tasked to
develop and field a system designed to conduct clandestine, remote, unmanned minefield
reconnaissance from a submarine. The system under development is the Near-Term Mine
Reconnaissance System (NMRS) under a "special category" acquisition program for
Fleet delivery and use. The NMRS entered operational use by the Type Commander
(TYCOM) in early Calendar Year (CY) 1998 and participated in
Demonstration II of the Joint Countermine Advanced Concept Technology Demonstration
(JCM ACTD).
The NMRS uses a submarine-launched, unmanned, underwater vehicle that provides
minefield reconnaissance in deep to shallow water. The NMRS incorporates SSN 688
torpedo tube technology hosted on a recoverable Underwater Unmanned Vehicle (UUV)
with multi-beam, active search sonar and side-scan classification sonar. The NMRS
consists of two reusable UUVs; launch and recovery equipment, including a winch and
drogues; and shipboard control, processing and monitoring equipment. Each UUV is
slightly shorter than an Mk 48 torpedo and is launched and recovered via a standard SSN
688-Class torpedo tube. The UUVs contain highly accurate sonar systems that can
pinpoint and classify mine-like objects. Batteries provide the power needed to propel the
vehicle during its sortie and operate the on-board electronic systems. Vehicle status,
position and sonar data are continuously relayed back to the host SSN via a fiber-optic
cable, thereby allowing continuous monitoring of the vehicle during sortie operations and
real-time analysis of data to the SSN from potentially mined waters.
The UUV is loaded backwards into the SSN 688 torpedo tube. Once ship conditions are
correct, the UUV backs out of the tube under its own power. Outside the SSN (but still
coupled to it via a steel cable and drogue assembly), it is towed to its mission area. The
UUV then releases from the drogue; fiber optic cable begins to pay out from both the
drogue and vehicle; and the UUV independently transits and conducts its mission. Should
the optic fiber break, the UUV is programmed to autonomously return to a pre-set
rendezvous point for recovery by the SSN. When the mission is finished, the UUV will
rendezvous and mate with the drogue. A winch located in the SSN torpedo room will then
pull the complete combination back into the torpedo tube. A trained Navy cadre will be
responsible for the operation and maintenance of the NMRS when deployed. Cadre
members are responsible to prepare and conduct UUV sorties; monitor vehicle status
during transit and operation; replenish the UUVs post-sortie; and compile analysis of
mission data.
Sources and Resources
http://www.fas.org/man/dod-101/sys/ship/weaps/nmrs.htm
Maintained by Robert Sherman
Originally created by John Pike
Updated Friday, January 01, 1999 6:34:14 PM
