After a relatively quiet 2004, the U.S. Missile Defense Agency (MDA) has a full battery of flight tests scheduled this year of both ground- and sea-based interceptor systems, agency officials said.

If all goes according to plan, 2005 will see three intercept tests of the Ground-based Midcourse Defense system, including the first in which the kill vehicle is launched from California rather than the Kwajalein Atoll, according to U.S. Air Force Lt. Gen. Henry “Trey” Obering, the MDA’s director.

There also will be another test of the Aegis sea-based missile shield, which successfully intercepted a target missile in February, and a resumption of flight testing of the Theater High Altitude Area Defense System after a two-year hiatus, Obering told reporters in a March 9 conference call.

Though disappointed by back-to-back Ground-based Midcourse Defense system test failures Dec. 15 and Feb. 13 — in both cases the interceptor rocket was unable to leave its silo at Kwajalein — Obering said the MDA gleaned valuable data from the attempts. In each case, he said, radars tracked the targets, launched from Kodiak Island in Alaska, and fed that data into the system’s computers, which generated firing instructions to the interceptor.

The first mishap was the result of overly conservative launch restrictions programmed into the interceptor’s computer and the problem was easily corrected, Obering said. In February, the interceptor did not launch because one of three support arms located within its silo failed to retract properly, he said. The investigation into that incident is continuing, but another test attempt could take place by late April, he said.

The April test, in which the interceptor is expected to approach without necessarily hitting its target, will be followed in June by an intercept test in which initial target-tracking data will be provided by an Aegis ship, Obering said. That would be followed in the fall by a test in which the target missile is tracked by radars at Beale Air Force Base, Calif., and engaged by an interceptor launched from Vandenberg Air Force Base, Calif., he said. Vandenberg is one of two sites where operational Ground-based Midcourse Defense interceptors are being installed, the other being Fort Greely, Alaska.

There also will be a pair of radar tracking tests this year that will involve launches of target missiles but not interceptors, Obering.

To date, six interceptors have been installed at Fort Greely and two at Vandenberg. Testing of the overall command and control system — called shakedown testing — is continuing, Obering said.

The MDA had planned to put interceptors at both sites on alert last year, but those plans have been deferred pending completion of the shakedown testing. Obering said the MDA has cut the time needed to switch the system into operational mode from hours to minutes, and over time that interval will be reduced even further.

In response to the two test failures, the MDA is conducting a comprehensive review of the ground support equipment for the U.S. missile shield, Obering said. The MDA also has appointed Rear Adm. Kathleen Paige, who has been overseeing the sea-based missile defense system, as its director of mission readiness, he said. In her new capacity, Paige will “ensure that the agency provides our military and civilian leaders with a system that is ready to conduct its ballistic missile defense mission when called upon,” the MDA said in a press release.

The failed December test was the first attempted intercept involving the U.S. territorial missile shield in two years. Obering said the MDA is shifting some Ground-based Midcourse Defense program funding from interceptor production to testing as that activity increases and in response to recent reductions to projected agency budgets for the next six years.

Meanwhile, the Aegis sea-based missile defense system, which did not fly any intercept tests in 2004, scored a success Feb. 24 in the first of two scheduled for 2005. Paige, who will retain her role as MDA program director for Aegis missile defense, said the test, in which a Standard Missile 3 (SM-3) Block 1 missile destroyed a target launched from the Hawaiian island of Kauai, met all of its objectives and marked several new milestones.

It was the shortest-range missile intercept to date by the Aegis system, Paige said. The target, designed to simulate a Scud missile, had a range of 500 kilometers and a flight time of about three minutes, she said.

The target was detected, tracked and destroyed by crews aboard the Aegis cruiser USS Lake Erie, which is outfitted as a missile defense test bed. The crews did not have access to the target-launch countdown information, relying instead on the ship’s radar. They then launched the SM-3 interceptor, which slammed into the target 2 kilometers short of its apogee, or high point in flight, at a distance of roughly 160 kilometers, she said.

The test was the first of the operational configuration of the SM-3 Block 1 missile, Paige said. The SM-3 Block 1 differs from the experimental SM-3 Block 0 interceptor used in previous tests in that it is more producible, can be stowed safely aboard ships for longer periods of time and has better target discrimination capabilities, she said.

Currently there are four SM-3 Block 1 missiles available for deployment, Paige said.

The test also successfully demonstrated the capabilities of planned system upgrades, Paige said.

Another Aegis intercept test is scheduled for this fall, and will be followed by joint testing with Japan, Obering said. The United States and Japan plan to spend a combined $1.4 billion from 2007 through 2012 to develop a new version of the SM-3, he said. The two nations are negotiating an agreement on that program, he said.

Warren Ferster is the Editor-in-Chief of SpaceNews and is responsible for all the news and editorial coverage in the weekly newspaper, the Web site and variety of specialty publications such as show dailies. He manages a staff of seven reporters...