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October 28, 2006

Aegis Ballistic Missile Defense: Target Tracking

Its electronic eyes on the skies, the Aegis destroyer USS Russell (DDG 59) detected the Aries ballistic missile as soon as it passed into the SPY-1 radar's line of sight, and sent tracking data through a tactical link to the Aegis cruiser USS Lake Erie (CG 70). The cruiser searched for the target with its SPY-1 radar, computed a fire control solution, launched a Standard Missile-3—and scored a direct hit.

This was the fourth successful intercept for the Aegis Ballistic Missile Defense System (BMDS). Named Flight Mission-6 and conducted on December 11, 2003 at the Pacific Missile Range Facility in Hawaii, the test was designed to check the long-range search-and-track as well as the ballistic missile engagement capabilities of Aegis cruisers and destroyers. And they passed.

The Laboratory played a key role in Flight Mission-6, as it had in previous flight-test missions. Work started long before December 2003 at the Pacific Missile Range. Months earlier, engineers and analysts used high-fidelity simulations to predict how SM-3 and SPY-1 would perform, and tested hardware and software in APL's Guidance System Evaluation Laboratory (GSEL). They defined mission requirements, established the test scenario, conducted debris analysis for range safety, and determined launch windows to avoid mishaps with Earth-orbiting satellites. At the test range, APL technical experts supported the Raytheon SM-3 launch team and manned consoles monitoring the target.

Success in missile defense isn't measured only by a few dramatic minutes of flight testing. Experts liken this complex engineering challenge to hitting a bullet with a bullet. APL staffers are part of the team developing and deploying a system to protect the nation from these potentially deadly weapons, and they're proving up to the task.

Command Directive. According to the DoD, more than 30 countries have ballistic missiles and more than 25 have or are developing nuclear, biological, and chemical weapons. In December 2002, President Bush directed the DoD to field an initial set of capabilities that could defend our homeland, deployed forces, and allies against near-term ballistic missile threats. The Missile Defense Agency responded by developing the BMDS to thwart ballistic missiles of any range, no matter where they are in their flight path.

The president's directive, combined with U.S. withdrawal from the Anti-Ballistic Missile Treaty, boosted the Aegis BMD program and activities at APL. Shipborne Aegis SPY-1 radar could now be used to detect and track intercontinental ballistic missiles (ICBMs) and relay that information to ground-based engagement elements. This capability is part of the Aegis BMD Block 2004 system, set for deployment on the first Aegis destroyers by the end of this year. The new system will soon be able to engage short- and medium-range ballistic missiles using SM-3, a guided missile that has clearly demonstrated its "hit-to-kill" ability.

History as Prologue. The Laboratory has been part of the Navy's BMD program since it began more than a decade ago. In 1992, the Strategic Defense Initiative Organization sponsored program to integrate SDIO-developed kinetic kill vehicle technology into an existing ship missile system. This led to the Terrier LEAP program, in which modified Terrier missiles were mated to light exoatmospheric
projectiles and launched from the (now decommissioned) USS Richmond K. Turner (CG 20).

APL was the technical direction agent for several Turner tests, built signal-processing hardware, and wrote software that enabled closure of the fire-control loop between Turner and the test facility at Wallops Island, Virginia. These initial tests provided significant advances in rocket motor technology and missile development, leading to the demonstration of an exo-atmospheric ballistic missile intercept with a new Standard Missile variant.

The Laboratory's critical contributions went far beyond Terrier LEAP. In parallel efforts, APL teams were developing a ballistic missile tracking capability for the Aegis SPY-1 radar. As early as 1993 they were conducting SPY performance predict and making ship sta recommendations fo Aegis participation the first Ballistic Mi Defense Organizatio sponsored Theater Critical Measuremen Program test.

In 1995, SDIO directed that Terrier LEAP technology be demonstrated withaninterceptandultimatelydeployedonAegis.The result was the Aegis LEAP intercept program, for which APL continued its traditional technical direction agent role for the SM-3 missile and expanded its support to other functional areas of the Aegis weapon system. The tremendous success of this program—three intercepts on the first three attempts—has opened the door to Aegis BMD becoming the sea-based component of BMDS Block 2004, the initial capability to provide a "modest" defense of the United States.

The Pace Picks Up. As the 2004–2005 deployment dates for the initial BMDS and SM-3 engagemen tcapabilities approach, the Laboratory's radar, missile, and systems engineers are supporting more than the high-visibility flight tests. They are evaluating the Aegis BMD Block 2004 design and assessing SM-3 flight performance using six-degree-of-freedom simulations, hardware-in-the-loop facilities in the GSEL, propulsion models, and analytical methods.

In addition, the Laboratory is conducting independent assessments of SPY-1 radar performance to determine its missile-tracking accuracy and acquisition times. Other APL staff are leading a multi-organizational team evaluating the ability of the Aegis BMD to transfer information and communicate with other components of the BMDS. Results of these assessments are being fed back to Lockheed Martin and Raytheon engineers in a cycle of constant system improvement.

A Continuing Partnership. The Aegis BMD program covers more than development and deployment of an effective BMDS; it lays the foundation for the next generation of Navy surface combat systems, including the development of radar, missiles, command displays, command/control/communications interfaces, and computer architecture.

APL played an important role in developing a naval BMD capability in 1992, has contributed substantially to the program since then, and now looks forward to continued success in this program that is critical to national security.

Testing Boundaries of Performance

APL conducts accurate Standard Missile-3 tests in its Guidance System Evaluation Laboratory, which contains a representative SM-3 kinetic warhead and the five onboard computers used to guide and control the missile. GSEL offers unique capabilities for testing SM-3 against realistic targets, from launch to intercept, in scenarios designed to fine-tune the system's software for deployment in 2005.

APL's test teams push the boundaries of missile performance under the stressing, simulated conditions in GSEL, giving program leaders confidence that SM-3 will perform as designed in uncertain and unfriendly environments.

Historic Hit

In December 2003, the Aegis BMD program scored its fourth successful intercept of a ballistic missile target during Flight Mission-6, but the test also marked significant firsts:

  • First flight mission to incorporate a full, lethal, aim-point shift, a function tht guides Standard missile-3's kinetic warhead toward the target
  • First flight mission to employ a reactive payloard in the Aries target, critical for gathering data
  • First shipboard use of missile telemetry to perform near-real-time kinetic warhead hit-point determination and ballistic missile kill assessment.