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Tracking the MTHEL Laser

A congressional decision to cut funding for a controversial laser defense program developed by Northrop Grumman may hasten its deployment in Iraq.
May 9, 2005

After more than ten years and several billion dollars of development, one of the most promising experimental weapons in the history of the Pentagon seemed to have fired its last shot. “The Army has no funding for MTHEL,” says Lt.Col. Jeff Souder, the project manager of  directed energy applications program at the Redstone Arsenal in Huntsville, Alabama.

The Mobile Tactical High Energy Laser (MTHEL) was a program to develop a defensive laser weapon powered by the combustion of highly volatile chemicals that shoots down artillery projectiles.

They system works by using a radar to track the incoming object, which signaled a controller to fire the weapon when the incoming shell was at its apogee, thus rendering it harmless to the troops below. Despite some 50 successful tests, the Army started to lose interest in the MTHEL after Sept. 11, switching its tact instead towards next-generation lasers that promise more mobility (and lower cost) than the bulky chemical laser of MTHEL.

Strangely, though, the death of MTHEL might be the best thing that ever happened to the program. Northrop Grumman, MTHEL’s lead contractor, and the Pentagon are in discussions that may see the laser prototype – which currently sits unused at the White Sands Missile Range in New Mexico – deployed in Iraq’s Green Zone later this summer.

That would be an amazing turnaround for a device whose development timeline moved at considerably less than the speed of light. Originally called the Nautilus, it was conceived in 1994 as a chemical laser test bed to determine if shooting down artillery rockets was feasible. It certainly did that well – the prototype laser has shot down at least 47 targets, some in salvos, including rockets, mortars, shells and even a helicopter.

President Clinton pushed up the development cycle in 1997, transforming the Nautilus program into a fast-tracked technology when he promised a string of the devices (since re-named THEL, and later MTHEL) to Israel to protect its Northern border from the rain of Katyusha rockets fired from the Lebanese militia group Hezbollah. He also invited Israel’s Ministry of Defense to be partner in development of the program.

Israeli interest in the weapon dimmed after 2000, when its Northern front turned peaceful after the Israeli withdrawal from Lebanon.

“The brass had a negative view of the MTHEL program from the beginning,” says Yiftah Shapir, an associate at the Jaffee Center for Strategic Studies of Tel Aviv University. “They didn’t want to spend $3000 on chemicals for every shot at a mortar shell which isn’t capable of doing that much damage even if it landed right on a house.”

Thus the Pentagon shifted the focus of its tactical laser requirements towards the long-term development of solid state lasers, which can be powered by electricity generated by diesel generators, which would take the place of the two or three support trucks filled with toxic chemicals like deuterium and nitrogen tri-flouride to power the MTHEL’s beam.

The problem with solid state lasers is that nobody has yet figured out how to make them powerful enough to shoot down artillery projectiles. In order to ignite a target, a laser must produce at least 100 kilowatts of power. So far, only one fourth that power has been reached in the laboratory.

“We’ve been hearing for years that 100 killowatts is only a year away,” says Art Stephenson, the vice president of Northrop’s Directed Energy Systems division. “But scaling up that far is a much harder engineering problem than anybody recognized.”

However, there may not be time to withhold the current MTHEL laser out of combat. Mortar and rocket attacks are the fourth-leading cause of casualties amongst U.S. forces, behind Improvised Explosive Devices (IED’s), suicide bombs and firefights.

To that end, Northrop officials have crafted a plan to pack up the laser and get it to where it’s needed most – Iraq.

“We can have it up and running in a few months – we’ve mapped out the logistics and the manpower and it’s doable,” says Stephenson.

The most logical place for the deployment in Iraq would be the Green Zone headquarters of the U.S. military and the new Iraqi government, which gets peppered with mortar fire emanating from nearby civilian neighborhoods. The Department of Defense refuses to comment on potential weapons deployment, but Stephenson says that a decision on the plan is imminent.

Besides its bid to use the single prototype for force protection, another proposal from Northrop is a $25 million “redeployable” THEL that is one fourth the size of the prototype and can be moved from site to site with a crane and an eighteen-wheeler. Stephenson claims a prototype could be available before the end of 2006 and that Northrop already has the manufacturing capability to produce one every two months from that point on.

“This isn’t a dream of the future,” says Northrop’s Stephenson. “This is a system which can be rushed into the field and start saving lives immediately.” He expects to hear from the Pentagon on a decision to fund the weapon within two months.

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