Air Defense: <b>May 9, 2005</b>

May 9, 2005

The U.S. Army is having a dispute over whether it should send its experimental laser anti-projectile system to Iraq, for some real-life action. The manufacturer, Northrop Grumman, wants the army to use the THEL (Tactical High Energy Laser) in a combat situation, to follow up on the recent successful tests of the system (where it knocked down barrages of incoming mortar shells.) Israel is a partner in development of THEL, which is not due to enter service until 2007. Its the laser that still needs work. But the THEL radar is already in good shape. Last year, Israel used the THEL radar to detect incoming Palestinian rockets fired from Gaza, and this provided an opportunity to operate the radar under combat conditions. The THEL system was designed to knock down larger, and better made, rockets than the home made Palestinian Kassam rockets. It could track the smaller Kassams, and may be able to knock them down with the laser. Meanwhile, American tests have shown that smaller targets, like mortar shells can be tracked and destroyed in flight.

The laser and radar system can track up to sixty targets (mortar and artillery shells, rockets) at a time and fire on and destroy these projectiles at a range of up to five kilometers. THEL can destroy about a dozen targets a minute, at a cost of some $3,000 per shot. Its taken eight years, and over a half a billion dollars, for American and Israeli engineers to get that far.

Aside from the systems size and cost, theres also the problem of lasers being weakened by clouds, fog, mist or even artificial smoke. For that reason, theres not a lot of enthusiasm for proceeding right now on such a bulky and expensive system. But by the end of the decade, the smaller, and cheaper, version will be more attractive, and likely to be purchased.

Currently, THEL is a bulky system, and not really mobile. Each system requires half a dozen or more large tractor trailer trucks to carry the radar, fuel supplies and laser. A new version of the MTHEL (Mobile Tactical High-Energy Laser) has been designed (using three tractor-traliers) and is being readied for testing. Engineers believe that MTHEL could be ready for battlefield use in about six years, at a cost of another billion dollars. In another few years, engineers believe they could create a MTHEL that could fit in a hummer.

In Iraq, however, there are several large American bases that are periodically being hit by inaccurate, but often damaging, mortar and rocket fire. THEL could be set up at one of these bases and demonstrate what it can, or cannot do. That may be why the army is not eager to send over a system it does not consider ready for prime time.