Buoyed by November’s successful intercept test of their sea-based missile shield under the most realistic scenario to date, officials with the U.S. Missile Defense Agency (MDA) are increasingly optimistic that the system is ready to protect deployed U.S. forces against theater-based threats.

The Aegis Ballistic Missile Defense System could even be pressed into service defending U.S. territory in an emergency, according to U.S. Navy Rear Adm. Alan Hicks, the MDA’s Aegis program director. A standardized configuration of the system should be ready to go on alert by this summer, Hicks said Dec. 19 in a luncheon speech sponsored by the George C. Marshall Institute, a public policy think tank here.

The Aegis Ballistic Missile Defense System features U.S. Navy cruisers and destroyers equipped to track and shoot down short- and medium-range ballistic missiles. Lockheed Martin Maritime Systems and Sensors of Moorestown, N.J., is the prime contractor for the effort, while Raytheon Missile Systems of Tucson, Ariz., builds the Standard Missile-3 interceptor rockets.

The Aegis system’s tracking radars also can be used to cue the Ground Based Midcourse Defense System, the U.S. territorial ICBM shield whose interceptors are stationed in Alaska and California , Hicks said.

The Aegis test conducted Nov. 17 marked the first time the system has been used to shoot down a target warhead that separated from its booster rocket. The MDA has worked closely with the Navy’s Operational Test and Evaluation Force, which is based in Norfolk, Va., to make the Aegis test program as realistic as possible, Hicks said.

The intercept, coupled with other data gleaned from the exercise, led the MDA to notify Congress that it intends to skip the next test in the planned series, which was scheduled for February, Hicks said. That will allow the program to save significant resources , he said.

MDA sources went further, saying the agency may have learned enough from the test to skip some risk-reduction activity planned for later in the program.

The overall U.S. missile defense effort is under fire from critics who charge that the Pentagon is rushing to deploy systems that have not been adequately tested. Among the critics is Philip Coyle, the former chief weapons tester at the Pentagon and now a senior advisor to the Center for Defense Information, a think tank here.

In a recent interview, Coyle said the Navy deserves credit for its recent Aegis intercept, and applauded the service’s efforts to make the test more realistic than the demonstrations of the Ground Based Midcourse Defense System.

But Coyle expressed concern over the MDA’s decision to skip February’s Aegis test. Missile defense is sufficiently difficult that the MDA should not grow overly confident in its abilities based on limited testing results, he said. “It’s very tough work,” Coyle said.

The MDA has scored six hits in seven attempts with the Aegis system, Hicks noted. The previous testing successes led the Navy to field an initial batch of interceptors that could be deployed for action in an emergency , the MDA sources said.

Meanwhile, the MDA is moving ahead with upgrades to the Standard Missile-3, which is based on an antiaircraft missile. The new Block 1B variant, expected to be ready in 2008, will feature a two-color seeker that enables the interceptor to better discriminate between warheads and decoys , Hicks said.

Other Block 1B improvements include a more capable divert and attitude control system — which steers the interceptor kill vehicle toward its target — that also is less expensive to produce than the existing model, Hicks said. Bringing down the cost of the rockets makes it easier to have more interceptors available, he said.

The Standard Missile-3 upgrade program also features close cooperation with Japan. The MDA and Japan hope to produce a faster interceptor known as Block 2 around 2012, Hicks said. The increased speed will allow the United States and Japan to defend larger areas using fewer ships , he said.

Three Aegis-equipped ships today are needed to defend Japan’s territory against short- and medium-range missiles, but with the Block 2 interceptor , one ship could do the job , Hicks said. He did not provide corresponding numbers for defending the U.S. homeland, and the MDA officials said that information is classified.

The MDA is open to working with other countries on the Aegis program as well, Hicks said. While Japan is the only country to contribute funding this far, others have expressed interest in doing so, he said.

The Aegis system is designed to knock down missiles in their middle phase of flight. The Pentagon previously had a sea-based program known as the Navy Area Missile Defense Program that was intended to intercept missiles in their terminal phase, or as they near their intended target.

The Pentagon canceled the terminal-phase program in 2001 after its projected cost increased by more than 50 percent. The MDA still needs to develop a terminal capability, but will likely defer that effort at least until 2008, Hicks said.

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