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WASHINGTON, 30 Dec. 2014. Ocean mine warfareexperts at the Northrop Grumman Corp. Aerospace Systems segment in Melbourne, Fla., will provide the U.S. Navy with a helicopter-based system designed to detect floating and submerged ocean mines with laser beams under terms of a potential $163.6 million contract announced last week.

Officials of the Naval Sea Systems Command in Washington awarded a $35.5 million contract to Northrop Grumman two days before Christmas to build and support the AN/AES-1 airborne laser mine detection systems (ALMDS).

The ALMDS electro-optical system will be mounted on Navy MH-60S helicopters based on the littoral combat ship (LCS). The laser-based mine-detection system uses streak tube imaging light detection and ranging (LIDAR) sensors to detect, classify, and localize surface and near-surface moored sea mines.

The ALMDS provides a revolutionary, high-area-coverage-rate capability that is organic to -expeditionary and carrier strike groups, Navy officials say. This contract includes options which, if exercised, would bring the cumulative value of this contract to $163.6 million.

The system, which will be part of the mine countermeasures (MCM) mission package aboard the new LCS, is designed for rapid wide-area reconnaissance and assessment of anti-ship mines in coastal waters, harbors, confined straits, choke points and amphibious assault areas where aircraft carriers and expeditionary strike groups must operate.

The ALMDS uses pulsed laser light and streak tube receivers housed in an external equipment pod on the MH-60 helicopter. These lasers are designed to search the water column from the surface to about 40 feet in depth -- the area where mines are the biggest threats and coincidentally where mine-hunting sonar systems are least effective. The system takes an image of the entire near-surface water column potentially containing mines.

The ALMDS projects a pulsed wide 538-nanometer blue-green laser beam into the water and samples at rates greater than 100 per second. ALMDS is capable of day or night operations without stopping to stream out or recover equipment and without towing any equipment in the water. It uses the forward motion of the aircraft to generate image data negating the requirement for complex scanning mechanisms.

The system is contained in a pod mechanically attached to the MH-60S with a standard Bomb Rack Unit 14 (BRU-14) mount and electrically via a primary and auxiliary umbilical cable to the operator console. Data is stored on a mass memory unit, and the ALMDS operator's console is common to all MH-60S airborne mine countermeasures systems.

The ALMDS was designed with VMETRO central electronics chassis (CEC) ---- liquid-cooled air transportable rack (ATR) systems with VMETRO CSW1 6U VXS (VITA 41) switch cards and VPF1 quad processor payload cards. The Curtiss-Wright Corp. Defense Solutions division in Santa Clarita, Calif., acquired VMETRO in 2008.

The CSW1 and VPF1 embedded computing boards process image sensor data using real-time multiprocessing over high-speed serial communications. The ALMDS CEC uses a combination of field-programmable gate arrays (FPGAs) and PowerPC processors.

The U.S. Navy has forward deployed the Airborne Laser Mine Detection System (ALMDS) to the 5th Fleet area of responsibility (AOR). ALMDS is a sensor system designed to detect, classify and localize floating and near-surface moored mines. Operated from the MH-60S helicopter, ALMDS provides rapid wide-area reconnaissance and assessment of mine threats in littoral zones, confined straits, and choke points.

Sailors from Helicopter Sea Combat Squadron (HSC) 26, Detachment 2, Laser Hawks, began the operational testing and demonstration of ALMDS in 5th Fleet on the system's maiden deployment August 4.

"The U.S. Fifth Fleet is focused on reducing the threat posed by sea-based mines in the region should that be necessary and the presence of ALMDS here in the theater adds to our capacity to do just that," said Vice Adm. John W. Miller, commander, U.S. Naval Forces Central Command, U.S. 5th Fleet, Combined Maritime Forces. "The international community has a critical shared interest in the free flow of commerce in this region. ALMDS, along with the many other counter-mine systems we operate in the Fifth Fleet allows the Navy to keep the sea lanes open."

"It's a laser-driven system that works like radar," said Lt. Cmdr. Theodore Lemerande, officer in charge of Laser Hawks. "It beams a laser down into the water and picks up reflections from anything it bounces off of. The system then registers the returned information and uses that data to produce a video image in order for technicians on the ground to determine what the object is."

The Navy's largest helicopter, the MH-53E Sea Dragon, has been a critical component of the Navy's ability to perform the airborne countermine mission in the Fifth Fleet and elsewhere for many years. ALMDS expands the countermine mission to smaller MH-60S helicopters.

"MH-60Ss have traditionally been a platform for anti-surface warfare, combat support, humanitarian disaster relief, combat search and rescue, aero-medical evacuation, and special warfare," said Lemerande. "ALMDS allows us to take airborne mine countermeasures technology to these smaller helicopters that can fly from smaller ships allowing us to take mine countermeasures into places that may not have been accessible before."