New system generates a fan beam and 3D imagery of mines in littoral waters

Northrop Grumman is producing a company-funded demonstrator of the Airborne Laser Mine Detection System (ALMDS) in a attempt to generate foreign military interest and highlight potential civil use of the helicopter-mounted sensor in advance of a US Navy $40 million engineering and manufacturing development (EMD) effort.

The US Navy's ALMDS, in development since last year, has completed a preliminary design review. Flight testing of the first of three EMD systems will not start before 2003. "This system is not driven by technology readiness," says John Kasko, Northrop Grumman director airborne mine countermeasures. "We see value in other applications and plan to show it commercially and internationally."

ALMDS uses a pulsed laser transmitter and a time-resolved streak tube receiver to generate a fan beam and three dimensional imagery of mines in littoral waters.

Laboratory testing has demonstrated high resolution images (less than 6.4mm/0.25in). Northrop Grumman believes that, in addition to foreign military users, the system is applicable to civil uses such as coastal mapping, surveying sandbars and fish location.

The demonstrator will be identical to the USN's planned 2.5m (8.2ft) long pod, but equipped with two rather than four receivers and a less powerful laser. Northrop Grumman plans to demonstrate from early next year a system mounted on a Bell 412 helicopter. The system will be equipped with its own power generator to avoid expensive helicopter modifications.

"We also plan to use it in navy exercises for mine detection. This will have value in that it gets the navy looking at the system early and minimises scrap and rework," says Kasko. The EMD version and any subsequent production version of the pod will installed on USN Sikorsky CH-60S Seahawks.

The ALMDS is intended to replace the navy's Kaman Magic Lantern system and is one of five airborne mine countermeasure systems being developed for the CH-60. The helicopter has conducted simulated airborne towing of the AQS-20 sonar, which will be used in conjunction with the Airborne Mine Neutralising System against bottom or moored mines.

Source: Flight International