
Laser weapons are a step closer to deployment on Earth's battlefields as a U.S.  defence company gears up to test a new land-based device.
Boeing has  announced that it has successfully mounted a 10kw solid-state laser on an  eight-wheeled, 500-horsepower truck that could be used alongside conventional  Army forces.
The High Energy Laser Mobile Demonstrator (HEL MD) is now  ready for field testing and over the next year will have a chance to show off  its ability to acquire, track and destroy targets.
The U.S. military has  long hoped to develop a land-based, laser weapon that could be used to shoot  down enemy missiles at the speed of light, but progress on the project has been  slow.
It is hoped that the new weapon can be used to defend ground forces  against rockets, artillery shells, missiles and unmanned drones by destroying  threats with a beam of super-powered light energy. 
U.S. and allied  troops currently have limited options to defend against rockets, artillery or  mortars. The short-range projectiles are airborne for only seconds, providing  little time to take cover. And using heavy gunfire might inadvertently hit  friendly forces in the process. 
But HEL MD’s laser beam, moving at the  speed of light - approximately 186,000 miles per second - will hit targets with  unprecedented precision and swiftness.
Mike Rinn, vice president of  Boeing Directed Energy Systems and director of the programme, said: 'The Boeing  HEL MD program is applying the best of solid-state laser technology to ensure  the Army has speed-of-light capability to defend against rockets, artillery,  mortars, and unmanned aerial threats - both today and into the  future.
'High power testing represents a critical step forward for this  innovative directed energy system.'
The latest field tests as part of  Boeing's contract with the U.S. Army Space and Missile Defence Command. Blaine  Beardsley, HEL MD program manager for Boeing, said: 'Phase II will allow us to  build on the great work we have accomplished over the past several years with  SMDC. 
'Our team is eager to demonstrate that this revolutionary system  is capable of saving lives and ready for the battlefield.'
The U.S.  military is seeking contractors to build it miniature 'suicide drones' that can  be flown into targets up to six miles away.
The little planes, which  could look like the remote-controlled aircraft used in a more domestic setting,  could be used for kamikaze-style attacks on vehicles or buildings - even  individuals if necessary.
The Army wants the weapons, known as the  'Lethal Miniature Aerial Munition System' (LMAMS) into war by 2016, and describe  the weapon as a 'portable, covert weapon with strike capability against  stationary or moving individuals, with a very low risk of collateral  damage'.
The 'plane' will consist of a drone, warhead and launching  device with a maximum weight of less than five pounds.
The aim is to fit  the entire plane in a backpack, and be able to fly it two minutes after a target  is agreed on. 
At that point, the plane must be able to fly for 15 to 30  minutes across up to six miles of territory before hitting its  target. 
The Pentagon has long been keen to develop laser weapons, and  not just because of their ubiquity in science fiction. 
Proponents of  laser guns claim they are capable of incredible speed and precision coupled with  relatively low cost and a seemingly near-infinite supply of 'ammo' constrained  only by the availability of electricity.
However, developing weapons to  the stage where they are ready for battlefield use has so far proved a challenge  as researchers battle with problems like cooling, efficiency and  miniaturisation.
In recent years other defence contractors including  Raytheon and Northrop Grumman have demonstrated ship-mounted lasers capable of  shooting down aircraft and disabling small boats.
The U.S. military has  been experimenting with laser weapons since the Seventies but it is only in the  past few years that a high-energy laser has properly functioned as a  weapon.
Early systems used large, chemical-based lasers which tended to  produce dangerous waste gases. More recently, scientists have developed solid  state lasers that combine large numbers of compact beam generators, similar to  LEDs.
The 10kw capacity of Boeing's latest effort is fairly modest  compared with the power levels the Pentagon hopes to eventually achieve. The  threshold for weapons-grade lasers is generally considered to be 100kw. Boeing  said their system could 'subsequently' incorporate a more powerful laser.