Engineering and Integrating the Ballistic Missile Defense System

David S. Eccles

Since the early 1980s, The Aerospace Corporation has helped develop different elements of what is now being integrated as the nation's Ballistic Missile Defense System. More recently, Aerospace has been leading a research team supporting systems engineering for this complex system.

Today, for the first time, the United States has in its arsenal a system capable of defending against a limited ballistic missile attack. The system is complex, and consists of many components or elements, as well as an extensive infrastructure that ties the far-flung pieces together. Some have compared the effort to build this system with earlier U.S. efforts to construct the first atomic weapon or land a man on the moon. While such comparisons are perhaps overdrawn, it is true that no such system existed before President George W. Bush directed the partial deployment of a Ballistic Missile Defense System (BMDS) by 2004.

At the time, the United States possessed a set of autonomous weapon and sensor systems, each with its own set of requirements and funding, and each being acquired independently by different branches of the armed services. But there was no integrating framework to bring the various elements together. Still, an extensive legacy of research and development to explore the feasibility of building such a defense system had begun during the Reagan administration, so this new effort was not starting from scratch. In 1983, the Strategic Defense Initiative Office (SDIO) was formed, and had begun to assemble existing capabilities and to develop ways of flight testing many of these elements.

In 2002, the various missile defense efforts were assembled under the newly formed Missile Defense Agency (MDA). This included the Army's ground-based missile defense and Theater High-Altitude Area Defense programs, the Navy's Aegis ballistic missile defense program, and the Air Force's Space Tracking and Surveillance System and Airborne Laser program. The Army's Patriot program was also brought under the MDA for program management and integration.

independent launch-readiness verification process

The MDA has taken the classic systems engineering "V" and modified it to support capabilities-based acquisition. The colors represent major stakeholder organizations and cover those portions of the "V" in which they play a major role. The systems engineering organization (in blue) is involved throughout the process, and leads the first three phases of plan, define, and system design. The Command and Control, Battle Management, and Communications (C2BMC) program (in magenta) is the integrating element and provides communication and networking infrastructure. The program elements (in yellow) participate throughout the process, but have responsibility for the element design, build, and fielding phases. The testing and assessment organizations (in green) lead during the test, verify, and assess phases. The integrate phase involves everyone. Warfighter feedback can occur at any point in the process. The BMDS roadmap (upper left corner) provides key input to the systems engineering "V." The roadmap is based on input from many sources, including the U.S. President and Secretary of Defense's national security strategy, the intent of the MDA director, and those capabilities set as priority by U.S. Strategic Command. The MDA is revising this diagram to reflect increased warfighter participation, and a new version is expected shortly.

The Systems Engineering Challenge

The MDA was directed to deploy an initial capability to defend against ballistic missile threats to the homeland, deployed forces, allies, and friends. Aerospace personnel had been assigned to assist the agency as it faced the formidable task of integrating and delivering a system capable of responding to real threats, and perhaps even more importantly, of adapting to evolving threats.

The basic premise of integration for the BMDS is the idea of a layered defense, one in which the various components of the system whittle away at an incoming raid. Ballistic missiles have a boost, midcourse, and terminal phase, so defensive capabilities that address these phases can be combined to produce a much more effective total system than one in which the various components stand alone. The system would come to be defined by an approach of capabilities-based acquisition, spiral development, two-year delivery blocks, knowledge points, and an MDA dedicated testing infrastructure. Aerospace led a team of laboratory experts that assisted in defining this approach for integrating the BMDS.

Competition among organizations for funding, talent, roles, and responsibilities developed as the various program offices and elements were integrated into the newly formed MDA. Each of these offices and elements faced their own technical and programmatic challenges. Each had a unique culture and view of how its mission should be executed, and each faced political, technical, and programmatic constraints. Each program office had stakeholders with equities to be defended, and each was used to working autonomously, pursuing a clearly defined mission.

BMDO (Ballistic Missile Defense Organization) had largely been a research and development organization prior to its becoming the MDA. The assignment of a set of missions and a goal for delivery changed the priority of the group from research to acquisition, which presented a major challenge for staff used to a research and development environment. Meanwhile, the processes for overall systems engineering and integration of such a complex system did not exist, and had to be quickly defined.

The Aerospace "Space Vehicle Systems Engineering Handbook" defines systems engineering as an effort "to ensure that a desired system is designed, built, and operated so that the system accomplishes its mission in the most cost-effective manner possible, considering performance, cost, and schedule risk." This definition assumes that the systems engineer has significant control over system components and can either control or strongly influence the allocation of resources to solve system issues. This ended up being only partially true at the MDA.

Deploying an Initial Capability

How would an initial BMDS capability become functional in two years under these circumstances? First off, Congress and President Bush agreed (at least initially) to establish a fairly stable funding stream of $8 billion to $10 billion a year. Additionally, although the national security directive gave a somewhat broad description of the BMDS mission (to defend the homeland, deployed forces, allies, and friends against ballistic missiles), a clear, near-term priority was set to defend against threats from North Korea, along with a schedule-get it done by December 2004. Another key aspect of setting the stage for a functional system was the withdrawal of the United States from the Anti-Ballistic Missile Treaty in 2002. Finally, national leadership has kept agency directors at the helm of the MDA for long tenures (at least four years) to ensure accountability.

The Office of the Secretary of Defense also agreed to make significant changes to enable the MDA to do its job. Federal acquisition regulations were relaxed. Operational and existing requirements documents were canceled, and the associated Joint Requirements Oversight Council participation was removed. The director of the MDA began reporting directly to the Office of the Secretary of Defense, Acquisition, Technology, and Logistics. The defense office also provided written guidance to the MDA, directing that a capabilities-based acquisition approach be used because of the rapidity with which the system had to be deployed.

The next factor that influenced the deployment of an initial system was the formation of a national team of government, industry, federally funded research and development centers and SETA personnel who could provide a central, systems engineering and integration function within the MDA. The industry portion of this team is headed up by Boeing and is made of experts in missile defense. The Command and Control, Battle Management, and Communications element is led by Lockheed-Martin.

The laboratory team led by Aerospace assisted in developing an initial defense operations plan that outlined what elements could be developed and deployed between 2004 and 2005. The selected components were loosely integrated with a basic command and control network and communication links. These capabilities were organized around a set of sensor, network, and weapon interactions called engagement sequences. Engagement sequences that shared common weapon systems were formed into groups of capabilities. Delivered in two-year blocks, these groups began to characterize new additions to the BMDS.

The initial defense operations plan focused on what elements were ready to be fielded. Corresponding specifications and interface documents recorded the requirements and characteristics of the system as built rather than directing various elements to do something new. Initially, there was no attempt to produce an overall architecture description of the BMDS. Because the threats were rapidly changing and there was uncertainty about what the new system would actually be able to do, any grand design might hinder spiral development. Spiral development is an iterative process that allows program objectives to be refined as technology matures. The BMDS needed to be flexible so that it could acquire and field new capabilities as they became operational.

Remarkably, an initial defensive capability was available for operations by the summer of 2005. In July 2006, the continuously augmented system was placed on alert and was available to President Bush during the infamous North Korean test launches.

During its first three years, the MDA made significant progress and was able to field an initial system of existing capabilities. However, major problems remained. The system was loosely coupled, not truly integrated, and adding capabilities required major new development activities that were hard to achieve within cost and schedule constraints.

For example, the Command and Control, Battle Management, and Communications system, which originally focused primarily on situational awareness, was now responsible for tasks involving sensor management, targeting, and weapon system assignment. Integration of the elements and the capability-based acquisition approach that allowed for the evolution of functionality had become vitally important to the future development of the system.

Capabilities-Based Acquisition

Traditional, threat-based acquisition assumes precise knowledge of a future threat. For example, during the Cold War, the United States had a good idea of how the Soviet threat was evolving, and could predict, years in advance, what requirements would need to be fulfilled by a particular system to neutralize the threat.

Today, the BMDS is aimed at a much more fluid and uncertain set of adversaries. Although intelligence sources can provide specific details about threats, most of what is known is only overall, general characteristics of the missile threats the United States might face. Nor can the United States predict which nations or nonstate actors might threaten its interests or those of its friends and allies. A capabilities-based acquisition strategy provides flexibility for introducing new, incremental capabilities to rapidly meet these uncertainties.

A capabilities-based acquisition strategy also allows for new technological advances and systems that have been demonstrated as useful to the military to be added as soon as they are ready, even if they do not pass a previously established performance threshold that might now be outdated. The point of this strategy is to get what is available out into the field and then improve it gradually over time to meet changing threats. The approach emphasizes using existing technology over hoped-for future developments. Hence, spiral development becomes a natural way to implement capabilities- based acquisition because the emphasis is on improving and developing the system over time as resources allow.

Three constraints come together to define capabilities-based acquisition requirements: what can industry do for certain, what can the threat do beyond current capability, and what can be afforded. These capabilities are organized into blocks of functionality that will then be developed and fielded. Each block has well defined capability increments or "spirals" for which the cost and schedule is considered well known. The contents of a particular block are related to either a specific mission (e.g., defense against Iran) or to a set of closely related capabilities, like near-term discrimination. Future capabilities with lower technology readiness levels or significant development risks remain in the capability development phase rather than a specific block. For example, the Multiple Kill Vehicle and Space Tracking and Surveillance System are program elements in the capability development category.

The BMDS Test Bed

The MDA has an extensive test program that includes complex system-level integration tests, ground tests, and flight tests. These tests are facilitated by a vast infrastructure of launch sites, including those at Kodiak Island, Alaska; Vandenberg Air Force Base, California; Barking Sands, Kauai, Hawaii; and Kwajalein Atoll, Marshall Islands. The tests also include the integration of ship-, land-, and space-based sensors, communication links, and integration/simulation facilities in Colorado Springs, Colorado, and Huntsville, Alabama. This BMDS test bed allows for new capabilities to be thoroughly exercised and evaluated before they are fielded.

In the past, before there was an attempt to integrate components, many of these tests focused on particular program elements. But the MDA makes each element flight test into a system test event by including additional test objectives that involve other supporting sensors, weapon systems, and communication and battle management systems. These integration tests often include hardware-in-the-loop components along with simulated components to expand the reach of each test event. The test bed also supports experimental activities and even war games that look at various potential future timeframes for capability deployment.

The purpose of the test bed is to support the evolution and maturing of ballistic missile defense capabilities. Potential capabilities can be developed and entered into the testing process, gradually becoming more mature over time. Promising capabilities can continue to be developed, while capabilities that fail to show promise are weeded out. Eventually, a capability deemed sufficiently mature enters development as part of a block.

test of the Ground-Based Midcourse Defense

Sept. 28, 2007: A ground-based interceptor is shown shortly after liftoff from Vandenberg Air Force Base. The launch was a test of the Ground-Based Midcourse Defense element of the Ballistic Missile Defense System. The missile intercepted a long-range target that had been launched from Kodiak, Alaska, several minutes earlier (courtesy of US Air Force).

Knowledge Points

Preplanned events that lead to critical program decisions are considered knowledge points. These key test events or demonstrations offer decision-makers current information that helps them make incremental financial commitments to a program, make schedule adjustments, set performance requirements, or even decide to stop a program and take an alternative path.

Knowledge points are not routine ground or flight tests, design reviews, war-game results, or asset deliveries, but are tailored to a program's critical risks and are usually unique to each program. Examples of knowledge points might be the first full-duration burn of a new rocket engine, or the first successful full-power test of a new laser. These are usually events that have never before been demonstrated.

Knowledge points are crucial to the maturity of ballistic missile defense capabilities. The promotion of new capabilities from development to block status relies on their successful execution. Knowledge points are not always related to technical pass-or-fail events, but can also be related to political or congressional funding events.

Conclusion

The MDA might be considered a fleet of ships steaming in the same direction towards the goal of an integrated national missile defense system. Like a fleet, the MDA has many different types of ships, aircraft, and sensors that perform specific missions. New capabilities, like new ships, aircraft, or sensors, are under continuous development, and with proven military utility, can be added to the existing flotilla. All of these systems must be integrated for effective use so they can take advantage of a common infrastructure.

The key to successfully integrating these formerly independent elements and programs will be consistent implementation of capabilities-based acquisition and the associated systems engineering processes, as well as the development of architectural options for future development. The architecture options need to become the framework used by each ship to determine where it fits in the fleet and in which direction it should turn. The effective application of knowledge points provides the navigation necessary to the fleet.