DARPA orders 'fridge-sized' laser energy cannon

American weaponry researchers have awarded a $21m contract for the design and development of a 150-kilowatt energy weapon, high-powered enough to blast missiles out of the sky yet light enough to be carried by a jet fighter.

The cash-in the newly-inked deal goes to Textron Defence Systems, who will in return "fabricate and test a Unit Cell Module for a 150 kilowatt Laser Weapon System (LWS) and develop a critical design for the 150kW LWS".

One need hardly add that the greenbacks come not from any normal US government weapons lab but rather from DARPA, the Pentagon's very own inflight pieshop.

In this case, however, the agency isn't seeking pie in the sky so much as rayguns in the sky. The idea of the agency's High Energy Liquid Laser Area Defence system is to make combat-power lasers light enough to put on "tactical aircraft" - that is, fighters rather than great big transports. Present-day rayguns are so heavy that they can only be lifted by C-130 haulers or jumbo jets.

It's nice to put energy cannons in the sky, according to DARPA, because they shoot in straight lines. Anything beyond the horizon can't be blasted, meaning that a laser on the ground can't engage low-flying or surface targets unless they come close.

A patrolling raygun fighter, in DARPA's thinking, would be able to blast bombardment rockets, artillery shells and suchlike in mid-flight across a large region - hence the "area defence" tag. If anyone sought to meddle with the aerial raygun umbrella, perhaps using a pesky anti-aircraft missile, that too could easily be beamed out of existence.

"The capability to shoot down tactical targets such as surface-to-air missiles and rockets will be demonstrated," according to DARPA's programme chief, Don Woodbury.

Textron Systems’ Dr John Boness believes that the DARPA cash will “accelerate the deployment of practical Directed Energy Weapons to the warfighter".

Originally the HELLADS system was to use a liquid laser medium pumped by light-emitting diodes - hence the name - but Textron now say they will be using "proprietary ThinZag® Ceramic solid-state" tech. DARPA have previously said the final 150kW demo module should "weigh just 750 kilograms and fit into a space about the size of a large refrigerator".

This isn't exactly pocket-size, but compared to solid state laser weapons already on sale HELLADS would be about a third the weight for a given level of output power. That could be enough, as DARPA suggest, to enable the long-desired shift from boring old laser tanks to raygun fighters.

One need hardly add that the bonkers-boffinry outfit has plans to fit its new fridge-sized beam cannons to flying robots too. We also confidently anticipate the announcement of plans to tinker with sharks' DNA so as to produce larger and more powerful specimens with especially strong necks. ®