LASER PROJECT LAGGING BUDGET GOES SKY-HIGH FOR 747 ANTI-MISSILE TOOL.

Byline: Jim Skeen Staff Writer

EDWARDS AIR FORCE BASE - Creating an airborne laser mounted in a modified 747 to swat down enemy missiles is proving to be more difficult and more expensive than the Pentagon expected.

Originally projecting it to cost $2.5 billion, the Pentagon has spent $2.1 billion since 1996, requested another $474 million in the 2005 defense budget and is expected to seek a comparable amount in the 2006 budget.

A test originally planned for this year in which the aircraft would shoot down a missile target has been postponed. No new date has been set. Defense officials said there are uncertainties with the schedule and that they are focusing on incremental steps to advance the technology.

``We want to take it one step at a time,'' a Defense Department official said. ``We're doing the grunt work now.''

In testimony this month before the Senate Armed Services Committee, Missile Defense Agency director Lt. Gen. Ronald Kadish acknowledged the program's difficulties, but asked for patience.

``At this time there is no reason to believe that we will fail to achieve this capability,'' Kadish said. ``This is such a revolutionary and high payoff capability. I believe we should again be patient as we work through the integration and test activities. But the risks remain high.''

Pentagon officials said progress has been made on demonstrating equipment that can track intercontinental ballistic missiles.

The program is aimed at developing a weapon capable of destroying enemy missiles with an invisible beam of energy, in response to worldwide threats posed by missiles like the Scuds launched by Iraq against Israel and against American forces during the first war with Iraq.

Firing short, intense bursts of energy from a laser mounted in a special turret in its nose, the plane will blow apart ballistic missiles shortly after launch, while they are far from their targets.

There are about 650 people working on the program at Edwards Air Force Base, which is housing the ground and flight test work.

For the laser testing, the Air Force spent $22 million to build more than 60,000 square feet of laboratory space at Edwards, including a facility capable of simulating conditions for weapons firing at 40,000 feet above the Earth.

The next major milestone for the program is what officials are calling ``first light,'' in which the laser light will pass through six modules mounted inside an airplane fuselage being used for ground testing. The modules, each weighing more than 3,000 pounds, are like batteries that will power the weapon.

If the military can get the weapon to work well enough for service, the airborne laser aircraft will patrol in pairs at more than 40,000 feet and inside friendly territory, scanning the horizon for missiles. When a missile is detected, a tracking laser beam will illuminate it, and computers will measure the distance and calculate its course and direction.

A second high-energy laser, fired in a three- to five-second burst from the nose turret, will destroy the missile.

The beam will heat an area about the diameter of a basketball on the missile's relatively fragile fuel tank casing. The laser will weaken metal already under high pressure from the ignited rocket fuel.

The high-energy laser will be fueled by the same chemicals found in hair bleach and Drano, respectively - hydrogen peroxide and potassium hydroxide. Those chemicals will be combined with chlorine gas and water.

The Edwards testing will include ground testing of the laser system as well as flight tests of various systems, including target tracking.

Air Force officials say 30 nations have ballistic missiles comparable to the Iraqi Scud - one of which killed 27 American troops in a Saudi Arabian barracks during the Gulf War - and that there are more than 10,000 such weapons in existence.

Jim Skeen, [phone]

james.skeen(at)dailynews.com