The Airborne Laser ballistic missile defense (BMD) system development program showed further progress, the Missile Defense Agency (MDA) announced.

ABL successfully accomplished basic steps required to complete a fire control loop (sequence of events) to engage a boosting ballistic missile, according to MDA.

ABL involves a highly modified Boeing 747 aircraft by prime contractor The Boeing Co. [BA], housing a Northrop Grumman Corp. [NOC] high-powered laser that can destroy an enemy missile shortly after it blasts off from a launch pad or silo, and a beam control/fire control system by Lockheed Martin Corp. [LMT].

While the seven envisioned ABL aircraft would be expensive, they would provide a cheap way of defeating enemy missiles. A laser beam firing costs far less than firing an interceptor missile, which is the method used by other BMD systems.

However, Congress is moving to cut ABL funding from the $549 million that President Bush and the Pentagon requested, down to as low as $299 million that the House provided in its defense financial plan bill.

Funding cuts were ordered with an argument that ABL development is less advanced than some other BMD systems.

Yet ABL has achieved a series of successes in recent months, augmented by the latest announcement of the June 29 test. MDA and the contractors flew the ABL aircraft from the West Coast to Andrews Air Force Base near Washington to show it to members of Congress recently.

The exercise last month included the first in-flight propagation of the Surrogate High Energy Laser (SHEL) through the nose-mounted turret of the ABL aircraft, a boost-phase missile defense system that is designed to use directed energy to destroy a ballistic missile in the boost phase of flight.

During the test, the modified Boeing 747-400 freighter first used its infrared sensors and beam control sensors to successfully find and track Big Crow, the target aircraft used for the test.

On this initial test of the SHEL, ABL made use of beacon lasers installed on Big Crow to simulate the targeting return it would receive from a live missile target.

The SHEL is a low-power laser used to simulate the characteristics of the high-energy Chemical Oxygen Iodine Laser that will be installed on ABL beginning later this year. The high-power laser has completed more than 70 successful firings during ground testing, according to MDA.

Completing the basic fire control process of an engagement sequence marks a significant step in the rapid technical and engineering progress achieved by the ABL program over the past three years.

In subsequent tests planned for later this month, the ABL will conduct a complete engagement series using its tracking illuminator laser, its atmospheric compensation laser, and the SHEL.

The SHEL was installed on the ABL aircraft during aircraft ground modifications and is an important component to test ABL powers to compensate for atmospheric distortions and deliver sufficient power on target to destroy a boosting ballistic missile shortly after it is launched.