By Jim Wolf
WASHINGTON (Reuters) - A high-profile test of a missile-destroying laser aboard a converted Boeing Co 747 aircraft has been postponed for a third time because of a technical glitch, the Pentagon's Missile Defense Agency said.
The agency cited an unspecified problem with a tracking camera's cooling system. Repairs could not be completed to fit the test window available at a range off the California coast on Tuesday night, it said.
The goal is to shoot down a mock ballistic missile more than 100 miles away, twice the range demonstrated in a maiden test on February 11, using the airborne chemical oxygen iodine laser.
Army Lieutenant General Patrick O'Reilly, the agency head, told reporters earlier on Tuesday the follow-on test was postponed over the past two weeks because of successive technical problems.
The first was with a stand that holds the target. The second was a problem on one of the tracking systems' software modules, prompting a system reboot, he said.
"We learned so much from that first test that our conclusion was we can operate at twice the range we thought ... and it may even have a greater range," he said.
O'Reilly said the delays reflected concerns with safety and a limited pool of target ballistic missiles that represent the perceived threat from countries such as Iran and North Korea.
The agency expects to be ready to run the delayed test in time for the next window of opportunity on the range, on Sunday, said Debra Christman, an agency spokeswoman.
Boeing provides the aircraft, battle management and overall systems integration. Northrop Grumman Corp supplies the megawatt-class laser and Lockheed supplies the beam control and fire control systems.
The laser's successful test in February prompted calls on the Pentagon to restore funding for further development of the system. Defense Secretary Robert Gates curtailed it to a research effort last year rather than a development program headed for possible deployment.
Boeing, the prime contractor, said in February the successful test "blazed a path for a new generation of high-energy, ultra-precision weaponry."
(Reporting by Jim Wolf; editing by Andre Grenon)