Topic: HELLADS

[Stormbringer]

HELLADS: Lightweight Laser Cannon
DARPA's HELLADS (High Energy Liquid Laser Area Defense System) will be light enough to fit on a fighter jet or drone aircraft, and yet powerful enough to fire a 150 kilowatt beam of energy. Star Wars laser cannon may be closer than you think.



(Star Wars Laser Cannons)
High energy laser weapons already in development are powerful enough to bring down missiles (see MTHEL - Mobile Tactical High Energy Laser). However, their very large size has precluded placement on any but the largest planes. The main weight problem comes from the cooling systems needed.

HELLADS makes use of a unique cooling technique. The high-energy laser uses a liquid that has the same angle of refraction as the mirrors inside the blaster. That way, the "ray gun" can fire away, even while it's being cooled. Currently in the third of five phases of development, a 15 kilowatt subscale prototype is being tested in the laboratory. In the next phase, the demonstrator device will be scaled up to 150 kW, and will specifically be targeted to achieve the low specific weight (5 kg/kW) and compact size need to be mounted in a smaller airborne vehicle. The final phase is engineering, fabricating, integrating and demonstrating the complete HELLADS weapon system on a tactical platform. The device will be built by General Atomics and the tracking system will be built by Lockheed.

This kind of compact system is getting very close to what science fiction writers since H.G. Wells have envisioned when writing about the heat ray in War of the Worlds. More recently, Larry Niven and Jerry Pournelle wrote about laser cannon in their 1974 novel Mote in God's Eye:


..."The intruder came from here. Whoever launched it fired a laser cannon, or a set of laser cannon - probably a whole mess of them on asteroids, with mirrors to focus them - for about forty-five years, so the intruder would have a beam to travel on...
(Read more about laser cannon)
Read more at MTHEL, Playing with Liquid Fire: High Energy Lasers Cool Down, HELLADS (at DARPA).

(Story submitted 8/25/2005)

[E_Look]

But how do you guarantee that the radiation will be absorbed by the target?

Even if this can be made tunable, in the case of missile, will you have time to match the right wavelengths?

[Stormbringer]

But how do you guarantee that the radiation will be absorbed by the target?

Even if this can be made tunable, in the case of missile, will you have time to match the right wavelengths?

by making the frequency "strong" enough you can guarantees that nothing will reflect it. for example x ray lasers cannot be reflected by even a silver mirror.

[Just plain old Punisher]

Besides, if you add a bunch of shielding to any airborne aircraft or missile, you also add weight...which in turn reduces range/endurance, maneuverability, and a host of other problems.

For the most part, you don't even need to destroy the piloted aircraft itself, if you aim the laser into the cockpit you can pretty much destroy the pilots eyesight.

[Tus-XC]

not any more though they have new visors (22 has them, that much i know) that will compensate automatically to block out laser light   however this don't mean that  if its a really strong laser it just won't fry him...

[Stormbringer]

Besides, if you add a bunch of shielding to any airborne aircraft or missile, you also add weight...which in turn reduces range/endurance, maneuverability, and a host of other problems.

For the most part, you don't even need to destroy the piloted aircraft itself, if you aim the laser into the cockpit you can pretty much destroy the pilots eyesight.

I think that the cooling scheme will be retroactively applied to the M-THEL which has knocked down hundreds of Rockets, missiles, artillery and mortars out ofthe sky in flight. M-THEL was passed on by the Military because it was just not very portable and had a huge footprint mostly due to cooling systems. check out the mthel. it is already proven to blast things from the sky!

[E_Look]

Well, if the beam is so intense that SOME energy is absorbed... like wow, how many watts are we talking about here?

Anyhow, with x-ray lasers or even just "regular" x-rays, they tend to penetrate and go right on through, reflecting back only a little, and very little being absorbed (wrong frequency!) but enough that it may blind those at its source!  No goggles that you can see through can stop it, really.

I used wonder, how come Star Trek's phasers never scattered enough after hitting a target, especially a shielded one, that the source of the phaser didn't get any "backflow".  I guess it may be the synergistic particles carried by the laser portion that gouge rough surfaces and holes in the target, but what about shields?

[Stormbringer]

personally the way i understand shield is they are a cold plasma (perhaps in localized contracted spacetime) as photons are abosorbed and electrons diplaced the beam decoheres. such that the rays are sent out in different directions and perhaps relayed through chains of ions in the shield in succession. the cold plasma also heats up. as the rays diverge the amount of photons actually making it back to the gun would be negligible. consider the distances involved in space. the mil formula states width  is equal to the range divided by angular width. so the further fron the origin of backscatter the wider the dispersal. and energy was lost as heat as well.

personally my  shield would be a density differential interface created by contracting a region of space around the ship. do this artfull enough and not only would no beam hit the ship no matter how powerful but such a beam could be redirected back at the source at full strength.

[Stormbringer]

M-THEL:

http://www.defense-update.com/directory/THEL.htm

Mobile / Tactical High Energy Laser
(M-THEL) Technology Demonstration Program
Developer: Northrop Grumman Corp.


The fixed-site version Advanced Concept Technology Demonstration (ACTD) Tactical High Energy Laser (THEL) THEL, was developed by TRW Inc. under a $89 million contract. During several tests in the USA, the system has shot down 25 Katyusha rockets, but has not been deployed.

The system also known as Nautilus, has not progressed much since the end of the demonstration program, since the lack of mobility and the fixed base limitations of the system made in insufficient to counter long range rockets currently employed by Hezbulla at the Israeli northern border with Lebanon. While Katyusha rockets had a range of 20 kilometers, and could hit only a few urban targets, the long range rockets have a range of 70 kilometers and can hit strategic facilities and large urban areas in the Haifa bay. A laser-based defense against such weapons must rely on more systems, which could be rapidly mobilized to protect a much larger area. Such design is currently being implemented under the MTHEL program. Similar threats could face US contingencies in other parts of the world. This requirement is driving the need for an air-mobile version of the beam weapon.

Mobile Tactical High Energy Laser (MTHEL)
A study completed in 2001 concluded that the rocket interceptor has "lots of promise" and further development should be pursued, primarily in enabling system's mobility. Mobility considerations for the future mobile systems include system mobility (road and off road capabilities) and air transportability, including the type of transport aircraft it should fit on (C-130, C-17 or C-5). Conclusions of these studies will define the necessary size- reduction technologies required for the future version.Further studies of the system include the use of such laser beam weapons to provide "hard kill" defenses against artillery projectiles, UAVs and cruise missiles.

During a recent test conducted on Aug. 24, 2004 the system shot down multiple mortar rounds, demonstrating potential its battlefield application for to protection against common threats. The test represented actual mortar threat scenarios. Targets were intercepted by the THEL testbed and destroyed; both single mortar rounds and salvo were tested.


Above: Sequence of a rocket intercept demonstration by e THEL laser, September 2000. In these photos, THEL/ACTD laser spot focus on the warhead (top) of the 5 inch diameter rocket, and detonate it (center), thus effectively "neutralizing" the rocket. The gases emitted by the explosion create excessive drag which tears the fragmentation casing into several parts which continue on their ballistic trajectory. (bottom of image series) Inside right: THEL Radar and fire control system.


THEL / MTHEL Operational Scenario
The Tactical High Energy Laser uses a high-energy, deuterium fluoride chemical laser to protect against attack by short range unguided (ballistic flying) rockets.

In a typical engagement scenario, a rocket is launched toward the defended area. Upon detection by the THEL fire control radar (image on right), the radar establishes trajectory information about the incoming rocket, then "hands off" the target to the pointer-tracker subsystem, which includes the beam director (top of page above). The PTS tracks the target optically, then begins a "fine tracking" process for THEL's beam director, which then places THEL's high-energy laser on target. The energy of the laser causes intense heating of the target, which causes its warhead to explode. The debris from the target falls quickly to the ground, far short of the defended area.

The purpose of the MTHEL program is to develop and test the first mobile Directed Energy weapon system capable of detecting, tracking, engaging, and defeating Rockets/Artillery/Mortars (RAM), cruise missiles, short-range ballistic missiles, and unmanned aerial vehicles. Despite the progress made with MTHEL, the US Army stopped funding for the program claiming it was too bulky.

Northrop Grumman proposed to use "relocatable" THEL systems to counter mortar and rocket threats on US military facilities in Iraq. Since funding for the MTHEL program was cut in 2004, such system may not be available for deployment in the near future. A second generation "relocatable" THEL system is currently considered for deployment. Such system will weigh about one-quarter the size of the current THEL and will fit into a 20 foot container which can be airlifted to forward areas. The new system will offer the same capability. Such systems are expected to cost $25 million a piece, when fielded in large numbers (30+). Future laser weapons will be based on electrically generated lasers and run on diesel fuel, rather than specially supplied chemical liquid fuel. However, while THEL based weapon could be fielded in less than two years, an equivalent system based on electrically powered laser will not be feasible before 2011. The system's radar is already operational in Israel, providing early warning from Palestinian attacks on the the city of Shderot. there are also rumors about a planned THEL deployment to Iraq, where it could provide RAM protection of the US Forces command and new Iraqi government.

 

[Stormbringer]

http://www.spectrum.ieee.org/WEBONLY/wonews/nov02/army.html

[Edited out all but last third of article]

Today that original THEL system, camouflaged to melt into the desert background, sits on a concrete platform at the Army’s High Energy Laser Systems Test Facility (HELSTF, White Sands Missile Range, N.M.). There, in addition to its recent victory over artillery, it has knocked down 25 of 25 Katyusha rockets to date. In such tests, a Katyusha is fired from a rocket launcher several kilometers from the laser. Seconds later the laser system detects the launch with its fire control radar and tracks the streaking rocket. The THEL laser optics are mounted on a large gimbaled assembly that swivels to track the target and keep the chemical laser beam directed at it. Within seconds of being struck by the laser beam, the 3-meter-long Katyusha explodes. The Army has touted the success of the system in a series of flight tests, but won’t disclose the specifics of the Katyusha’s velocities and range.

Until this past summer, the Army’s interest in the system appeared purely one of improving the accuracy of directed-energy laser technologies. Then, as Israel became more intent on developing a mobile version, the Army started rethinking its own plans, eyeing mobile THEL as a countermeasure for troops on the move. Along with other branches of the military, it is now considering mounting the laser on helicopters, ground vehicles, and destroyers.

On top of making it mobile, the Army is expanding THEL’s repertoire, according to Josef Shwartz, TRW’s program manager for THEL programs. The service needs a terminal defense system to protect troops and assets in the field from short-range missiles, artillery, cruise missiles, unmanned aerial vehicles, rockets and mortars, he said. The Army expects an MTHEL demonstrator up and running in 2006 or 2007.

This article has been updated.