Performance
The early analytical models coupled with chemical rate studies led to the design of efficient experimental CW HF laser devices at United Aircraft, and The Aerospace Corporation. Power levels up to 10 kW were achieved. DF lasing was obtained by the substitution of D2 for H2. A group at United Aircraft Research Laboratories produced a re-circulating chemical laser, which did not rely on the continuous consumption of chemical reactants.
The TRW Systems Group in Redondo Beach, California, subsequently received US Air Force contracts to build higher power CW HF/DF lasers. Using a scaled-up version of an Aerospace Corporation design, TRW achieved 100 kW power levels. General Electric, Pratt & Whitney, & Rocketdyne built various chemical lasers on company funds in anticipation of receiving DoD contracts to build even larger lasers. Only Rocketdyne received contracts of sufficient dollar amounts to continue competing with TRW. TRW produced the MIRACL device for the U.S. Navy that achieved megawatt power levels. The latter is believed to be the highest power continuous laser, of any type, developed to date (2007).
TRW also produced a cylindrical chemical laser (the Alpha laser) for DARPA, which had the advantage, at least on paper, of being scalable to even larger powers. However, by 1990, the interest in chemical lasers had shifted toward shorter wavelengths, and the chemical oxygen-iodine laser (COIL) gained the most interest, producing radiation at 1.315 μm. There is a further advantage that the COIL laser generally produces single wavelength radiation, which is very helpful for forming a very well focused beam. This type of COIL laser is used today in the ABL (Airborne Laser, the laser itself being built by Northrop Grumman) and in the ATL (Advanced Tactical Laser) produced by Boeing. Meanwhile, a lower power HF laser was used for the THEL (Tactical High Energy Laser) built in the late 1990s for the Israeli Ministry of Defense in cooperation with the U.S. Army SMDC. It holds the distinction of being the first fielded high energy laser to demonstrate effectiveness in fairly realistic tests against rockets and artillery. The MIRACL laser has demonstrated effectiveness against certain targets flown in front of it at White Sands Missile Range, but it is not configured for actual service as a fielded weapon. ABL was successful in shooting down several full sized missiles from significant ranges, and ATL was successful in disabling moving land vehicles and other tactical targets.
Despite the performance advantages of chemical lasers, the Department of Defense stopped all development of chemical laser systems with the termination of the Airborne Laser Testbed in 2012. The desire for a "renewable" power, i.e. without having to supply unusual chemicals like fluorine, deuterium, basic hydrogen-peroxide, or iodine, led the DoD to push for electrically pumped lasers such as diode pumped alkali lasers (DPALS).
Read more about this topic: Chemical Laser
Famous quotes containing the word performance:
“Still be kind,
And eke out our performance with your mind.”
—William Shakespeare (1564–1616)
“The audience is the most revered member of the theater. Without an audience there is no theater. Every technique learned by the actor, every curtain, every flat on the stage, every careful analysis by the director, every coordinated scene, is for the enjoyment of the audience. They are our guests, our evaluators, and the last spoke in the wheel which can then begin to roll. They make the performance meaningful.”
—Viola Spolin (b. 1911)
“O world, world! thus is the poor agent despised. O traitors and bawds, how earnestly are you set a-work, and how ill requited! Why should our endeavour be so loved, and the performance so loathed?”
—William Shakespeare (1564–1616)