WASHINGTON and LONDON -- Britain has developed and successfully tested a prototype directed energy weapon package applicable for use on unmanned air vehicles or standoff cruise missiles, with some of the weapon tests carried out in the U.S.

The defense ministry program to develop the high-power microwave (HPM) payload was underway by the mid-1990s. The payload is intended as a weapon for use against a target set including: command and control, communications, and air defense assets. It is conceivable a prototype HPM weapon could be fielded, if required, within the coming months.

TRIALS OF THE HPM payload have been carried out, with the directed energy weapon package flown in a test delivery vehicle. At least some of the trials were carried out on U.S. ranges, reflecting U.S. interest in the weapon.

Development of the HPM payload is believed to have involved U.K. government research laboratories and British industry. The payload was sized for Ryan Aeronautical's (now Northrop Grumman) BQM-145A medium-range UAV. The high-speed low-flying UAVs used could either be ground launched or dropped from an F/A-18-size aircraft.

One U.S. source suggested there was U.S. Navy interest in pursuing a joint program, but it remains uncertain as to the extent, if any, of continuing U.K.-U.S. collaboration.

The intent of an HPM weapon is to create an intense power surge in electrical systems, ideally causing permanent, irreparable damage.

British industry leaders readily admit to an interest in directed energy weapons; however, they decline to discuss any specific aspects of work they might be pursuing.

Five of the BQ-145A UAVs were turned over to the U.S. Air Force and are held by the UAV Battle Lab at Eglin AFB, Fla. Tests of the British payload were considered much more promising than an earlier test at Eglin that used modified air-launched cruise missiles. They were designed to produce a pulse of microwave energy when high explosives wrapped around a coil generating an electrical field were detonated.

A potential candidate platform, were the U.K. to operationally deploy an HPM weapon, would be the Storm Shadow cruise missile [shown pictured in foreground], which will enter service with the British Royal Air Force before the end of 2002.

"In the U.S., there has been a lot of research into DE [directed energy]," a senior British industry official said. "Fortunately, in the U.K. there has been some equivalent investment as well, so we are better placed than some of our [European] colleagues."

Germany has also been looking at HPM payloads for UAV applications. Manfred Lehnigk, an executive with Germany's STN Atlas Electronik, builder of the Taifun UAV, said that his company is looking at an HPM weapon for unmanned aircraft, but it will likely take a minimum of five years to turn the system into payload.

"The UCAV programs are highly classified, but we have taken the cover off various other projects, like HPM artillery shells, just to demonstrate that we are actively involved in all sorts of active variants of [electronic]-kill mechanisms."

However, he warned, the need for miniaturization and large power requirements will continue to dog delivery of airborne DE systems.

"I think increasingly you'll see the importance of being able to interrupt communications, be it command and control or straight communications processes," Lehnigk said.

"You will see continued focus on the disruptive soft kill. We've already seen examples, like Kosovo, where various non-destructive weapons were deployed to knock out electric power on a temporary basis," he said.

HPM also holds promise for attacking hardened and underground targets.

"TO GET AT a 100-meter-deep target, explosives may not be the answer," the British official said. "If you want to get underground, you have to start from the surface to get there. So you look at power lines, antennas, water pipes and ingress and egress sites" where metallic structures would conduct pulses of energy deep into the structure to damage sensitive electronics concealed there.

THE U.S. HAS LARGELY decided to use lasers from manned aircraft and HPM from unmanned (the latter in case fly-by-wire flight controls are damaged by the energy pulse). British researchers say they think there is a useful role for HPM from manned aircraft, but demur from being more specific, citing security restraints.

British timelines for having tactically representative directed energy weapons roughly parallel those of the U.S. with which there appear to be some collaborative efforts.

"Reusable HPM will be demonstrated in a couple of years and laser weapons a few years beyond that," said one British official. But unlike the U.S., there's "not the [single] concentration on disposable DE weapons" that could be mounted in cruise missiles or some type of bomb, he said, adding "we want reusable directed energy devices."

FIrst posted 7-26-2

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