Boeing and the U.S. Missile Defense Agency have moved closer to developing an airborne high-energy laser weapon that will shoot down an upcoming offensive missile.

The Boeing Co. said the successful first test involved firing the high-energy laser from a modified 747-400F into a calorimeter, also on board, to measure the power of the beam.

The test took the aircraft from Edwards Air Force Base to the skies over the California High Desert.

Once there and while still in flight the ABL Jumbo unleashed its laser striking the calorimeter, allowing experts to determine how much more power will be required to make the weapon effective in combat.

A Boeing statement in response to a United Press International query said the calorimeter or the "beam dump" -- a wall of metal aboard the aircraft -- was used to capture the laser energy and measure characteristics of the beam.

Asked if the laser will eventually be designed to respond to a hostile ground-to-air or air-to-air missile or a projectile weapon launched from a ship, Boeing said "the ABL program objective is to provide boost-phase missile defense capability. Further improvements are under development to track post-kill debris."

Analysts said the successful firing of the laser in flight has moved the development of the weapon closer to a demonstration flight when ABL shoots down an upcoming missile.

"This was a significant test of the Airborne Laser's capabilities, demonstrating that the system has truly moved from the drawing board to reality," said Greg Hyslop, vice president and general manager of Boeing Missile Defense Systems.

Michael Rinn, Boeing vice president and ABL program director, said the test showed that ABL was on track to shoot down a boosting ballistic missile in a demonstration planned for later in 2009.

After years of development, the team involved with the work is looking forward to perfecting what Boeing calls a "transformational and unique" weapon system, depicted in numerous movies and video games showing characters engaged in laser combat.

It will be the first time a megawatt-class laser has been coupled with precise pointing and atmospheric correction in an airborne environment.

Once ABL is deployed in real-time defense systems, it will significantly change warfare, just as radar-beating stealth technology has transformed rules of engagement, analysts said.

Unlike stealth technology, which began as a passive countermeasure against increasingly advanced detection technology, airborne laser offers both pre-emptive and offensive paths of development, analysts said.

As the tests continue the developers will be seeking to build ABL's lethal capabilities and ABL's applications in defense against aircraft, cruise missiles and surface-to-air missiles.

The project is being developed by Boeing Integrated Defense Systems, a Boeing Co. unit that is the world's largest manufacturer of military aircraft, with headquarters in St. Louis. It is a $32 billion business employing 70,000 people worldwide.

Although Boeing is the prime contractor, ABL's development is very much the result of team work. Northrop Grumman designed and built ABL's high-energy laser, Lockheed Martin developed the weapon system's beam control and fire control system, and Boeing provided the battle management system.