Crave

The U.S. Air Force has awarded Boeing a new contract worth up to $30 million for the next phase of development on the Advanced Tactical Laser.

The ATL is a C-130H aircraft outfitted with a 12,000-pound high-energy chemical laser module that would be used as a weapon against ground targets. It's the smaller sibling of the Airborne Laser, a highly modified 747 under development that packs a similar weapon but that would be used against ballistic missiles.

The Advanced Tactical Laser will use a rotating ball turret to fire its laser weapon at ground targets.

(Credit: Ed Turner, Boeing)

While the 747-centric ABL is designed to fire its laser through a bulbous nose apparatus, the ATL totes a belly turret reminiscent of the manned versions used in some World War II bombers.

The new Extended User Evaluation contract marks the start of a transition for the ATL, which Boeing has been working on as an Advanced Concept Technology Demonstration project. The EUE phase means another round of ground and flight tests, along with "hands-on operation" for the Air Force and other potential users.

Why use a laser when the Air Force already has a wide array of missiles and bombs at its disposal? (The standard gunship variant of the C-130 can already be equipped with 40mm and 105mm cannons.) "Little to no collateral damage," Boeing says, thanks to the laser weapon's "ultra-precision engagement capability." That is, think laser pointer with extreme prejudice.

In addition, the laser would presumably strike more or less silently--no thump-thump-thump or rat-a-tat-tat. (Note, 11:30 a.m. PDT: A reader writes in to say that high-power lasers operating in the atmosphere are anything but silent, perhaps because of ionizing the air - a la lightning.)

For use against missiles, mortars, and the like, laser weapons are intended to heat up and weaken the metal skin of the projectile, causing it to rupture while in flight. Against ground targets, the ATL could, say, zap fuel tanks or even vehicle tires--if it could hold focus long enough.

The A160T Hummingbird comes in for a landing May 9 at the U.S. Army's Yuma Proving Ground in Arizona after a high-altitude hovering demonstration.

(Credit: Boeing)

A disparate pair of aviation R&D projects at Boeing have hit milestones recently.

The A160T Hummingbird, a helicopter-style unmanned aerial vehicle, last week flew for 18.7 hours without refueling, an accomplishment that Boeing described Wednesday as an "unofficial world endurance record" for UAVs between 500 and 2,500 kilograms (about 1,100 to 5,500 pounds)--a record that's pending certification by a key aeronautical sanctioning body.

But the record books aside, the flight also helps to show the Hummingbird's mettle as a potential aircraft for military use. During the flight, the turbine-powered unmanned rotorcraft carried a 300-pound internal payload--which in eventual real-life operations might be supplies for ground troops or gear for in-flight surveillance--and flew as high as 15,000 feet. When it finished, it still had about 90 minutes worth of fuel in reserve.

In a test flight last September, the Hummingbird carried a heavier load for a shorter period of time (1,000 pounds and eight hours). The A160T variant first flew about a year ago, taking up where an earlier piston-powered version left off.

Another May milestone for the A160T Hummingbird, which is designed to fly autonomously, involved so-called hover-out-of-ground-effect flights at 15,000 and 20,000 feet. The ability to hover at the relatively high altitudes would make the UAV more effective for missions in mountainous areas and help keep it out of range of some ground-based air defense weapons, Boeing said.

Measuring 35 feet long with a 36-foot rotor diameter, the Hummingbird in service is expected to fly at 140 knots for more than 20 hours. Boeing Advanced Systems is building the UAV for DARPA and for the Army and Navy.

The Advanced Tactical Laser aircraft in flight.

(Credit: Ed Turner, Boeing)

Also this week, Boeing said that on May 13, it fired a high-energy chemical laser--in ground tests--aboard a C-130H aircraft, a step toward in-flight tests later this year in which the laser will fire at ground targets from on high. The directed-energy weapon is designed to fire through a rotating belly turret in the aircraft, known as the Advanced Tactical Laser.

And in a me-too missive straight out of the Cold War, the Russian news agency Novosti reported a patriotic response to the ATL test from an unnamed Russian defense industry "expert." Boeing, it would seem, is late to the game.

"We tested a similar system back in 1972. Even then our 'laser cannon' was capable of hitting targets with high precision," the expert is quoted as saying. "We have moved far ahead since then, and the U.S. has to keep pace with our research and development."

The Advanced Tactical Laser aircraft flies over Albuquerque, N.M.

(Credit: Ed Turner, Boeing)

The first ray guns to be used in combat may well be aerial weapons, and not phaserlike side arms in the hands of foot soldiers.

Certainly Boeing is working in that direction. For several years it's been providing regular updates on the (notably slow) progress of its marquee directed-energy effort, the Airborne Laser, to be carried aloft by a heavily modified 747 that's intended to stop ballistic missiles during their launch phase. Now the defense contractor is touting the steps it's taking with a smaller counterpart designed to strike ground targets, the Advanced Tactical Laser.

As of this month, the high-energy chemical laser that is the actual weapons portion of the ATL is now installed in a C-130H airplane, a well-proven design taking on yet another new mission. The 12,000-plus-pound chemical laser system is taking up residence alongside a separate beam control system, installed at an earlier date, that functions as the tracking and targeting apparatus.

This would hardly be the first time that the C-130, primarily a cargo and troop transport aircraft, has functioned as a gunship. The well-armed AC-130 variant saw much action in Vietnam, and has also flown in subsequent conflicts.

An earlier incarnation of the ball turret, in restored B-17 Flying Fortress aircraft flying in 2002.

(Credit: SSGT William Greer, USAF )

The business end of the ATL will be a rotating turret in the belly of the fuselage--reminiscent of the one-squished-man ball turret of the B-17 Flying Fortress and B-24 Liberator planes used in World War II, hauntingly depicted by poet Randall Jarrell in his "Death of the Ball-Turret Gunner." By contrast, the 747-borne Airborne Laser will fire through the nose of the aircraft.

Sometime in 2008, the ATL is expected to demonstrate its prowess in flight, directing the high-energy laser at what Boeing calls "mission-representative ground targets." In tests at Kirtland Air Force Base, N.M., earlier this year, a surrogate low-power laser hit targets on more than a dozen occasions, and laboratory testing of the high-energy laser wrapped up after more than 50 firings, according to Boeing.

Aerial tests of the bigger, ballistic-missile-minded Airborne Laser are scheduled for 2009.

Boeing doesn't just have its head in the clouds when it comes to directed-energy weapons. It's also working on a more down-to-Earth Humvee-mounted laser shooter.

The heat rays go marching one by one by...well, that's about it for now.

Raytheon said Tuesday that its Active Denial System 2 is now in the hands of the customer, the U.S. Air Force. Should it ever get beyond the evaluation stage, the ADS technology could be one of the very first directed-energy weapons fielded by the military. It looks like a satellite dish, works something like a microwave, and isn't supposed to cause any lasting harm.

Active Denial System 2 has been delivered to the U.S. Air Force.

(Credit: Raytheon)

What it's intended to do is beam short bursts of millimeter waves (which are smaller than the better-known microwaves) at a suspicious or unruly target--a crowd gathered outside a U.S. embassy, say--and make make the recipients scatter because they can't stand the heat. Literally. The ADS, which operates at 95GHz, causes an intense but skin-deep burning sensation that lasts only as long as a person is in the way of the beam, which in tests so far has been a matter of just a few seconds at most.

Version 2 is an upgrade of the earlier system. It's bigger, more rugged and handles warmer atmospheric temperatures better, Raytheon says. And that version number is also pretty much the number of the systems that have been built so far: Raytheon has tallied up just one unit in each of the phases. ADS 0 was the initial technology demonstrator, and ADS 1 was mounted on a Humvee for further tests and for public demonstrations. ADS 2 is designed to be mounted on a variety of vehicles or to operate from a fixed site.

What happens next with ADS 2 is up to the Pentagon, specifically its Joint Non-Lethal Weapons Program, for which the Air Force is the lead service. But the decisions on when, how and even whether to deploy are political as much as they are technical--ADS may be nonlethal, but the Pentagon surely isn't eager to see headlines like "U.S. fries protesters with energy weapon."

Raytheon, meanwhile, has a smaller version called Silent Guardian, at one-third the size and one-third the power, that it says is available to interested buyers. Better hurry, though. There's just one of these, too.