Page 8: of Maritime Reporter Magazine (October 1998)

INVESTMENT IN DESIGN

Clearing The Clutter

Litton's new Bridgemaster E system performed exceptionally well in tough cross- Channel conditions by David Tinsley, technical editor 8 Maritime Reporter/Engineering News been engineered for ease and econ- omy of installation and production, and with long-term dependability of operation as a design criterion of unsurpassed importance.

With Litton, now encompassing

Sperry Marine and C Plath as well as Decca, having decided to focus radar development at the latter's

New Maiden premises in the south

London conurbation, BridgeMaster

E provides a new reference point for U.K.-sourced maritime technol- ogy. The optional, revolutionary clutter suppression system, known as Vision, employs the latest adap- tive processing techniques. The equipment also represents an advance in control flexibility. Using a joystick, trackball or dedicated keyboard, operating functions can be accessed with easy point-and- click control, eliminating multiple layers of menus and sub-menus.

ARPA and ATA (automatic tracking aid) versions have the ability to track up to 40 targets simultane- ously at relative speeds up to 150 knots.

Ensuring the long-term depend- ability of the equipment was the top priority in the design program. "We instituted an unprecedented reliability testing program," said

Decca Marine's managing director

Clark Graham.

Certain aspects of the life-cycle testing, constituting the most rig- orous reliability evaluation ever conducted with a Decca product, have reached a stage equivalent to 23 years' service at sea.

Componentry testing has included the evaluation of the AC power supply of the transceiver over 264 hours at a temperature of 100- degC, well in excess of the type approval criterion of 55-degC. It is felt that if the power supply can operate without anomaly for 11 days continuously at such an extreme temperature, it will func- tion correctly throughout the life of the radar.

Tests have also encompassed the drive motor and gear of an S-band antenna rotating unit, which has been the subject of an operating cycle involving switching off eight times per day through an acceler- ated period corresponding to 15 years. The program has also entailed mechanical simulation of 100-knot winds acting on the antenna over a period of 8,000 hours, or nearly one year.

Each time there has been a breakage or failure, the event has been analyzed, the necessary recti- fication or modification has been made, and the test resumed. Such is the commitment to building the knowledge base that the study will be continued for the next five

A true mate for the

Mark I eyeball

A run across the English

Channel in a Force 8, with inter- mittent rain, provided a first-rate opportunity to get the measure of the latest generation of radar claimed to set a new standard of clarity in all weather conditions.

With the clutter suppression facility set to automatic on the new

BridgeMaster E equipment trialed on the P&O RoRo passenger ferry

Spirit of Burgundy, small as well as large shipping targets remained clear in the swell, spray and rain, as did inshore craft and breakwa- ters when fetching the coast.

Not only did the new series of radar provide a truly hands-off clutter and gain control capability, obviating the need for continual manual adjustments to the set- tings, it ensured that the elimina- tion of sea and rain clutter from the screen did not also obscure or reduce echoes from targets in that particular area.

A major strength of the

BridgeMaster radar family derived originally from Racal-Decca

Marine in the U.K. had been its combination of advanced technolo- gy with a thorough, practical understanding of watchkeeper's needs, in a period of far-reaching change in shipboard organization.

That essential recognition of the demands on the individual, parallel to acknowledgment of the ship opera- tor's ever-more pressing require- ment for tools of greater efficiency and safety, is reflected in the new breed of

BridgeMaster E radars developed by the Decca stable, as a constituent part of

Litton Marine

Systems since

February 1997.

Perhaps more than ever before, the lat- est equipment has