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Introduction and Background

Cruise missiles and ballistic missiles exist in large numbers in the tactical inventories of many potentially hostile nations. These weapons vary in their ability to evade detection by the military forces' defensive systems and in the accuracy with which they deliver warheads. In any case, however, they have a demonstrated ability to sink or seriously damage ships and to deliver warheads with high precision against stationary land targets. Among the more troubling aspects of the missile threat is the fact that almost all such weapons may be modified to transport nuclear, chemical, or biological warheads.

Since the development of guided missile systems in the 1950s, the Navy has had vigorous programs to protect itself against air threats. Shipboard antiair warfare (AAW) systems have been deployed for both ship self-defense and for area defense. The Navy developed air-to-air weapon systems to protect its tactical aircraft and to serve as an outer layer of ship defense. The AAW systems deployed by the Marine Corps have been primarily ground-based air defense systems. The relative importance of each of these systems has waxed and waned as naval missions, operational concepts, and threats evolved.

In this report, current and planned naval capabilities for theater missile defense are divided into three broad categories:

  • Antiship cruise missile defense (ASCMD),

  • Overland cruise missile defense (OCMD), and

  • Theater ballistic missile defense (TBMD).

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Page 13 1 Introduction and Background Cruise missiles and ballistic missiles exist in large numbers in the tactical inventories of many potentially hostile nations. These weapons vary in their ability to evade detection by the military forces' defensive systems and in the accuracy with which they deliver warheads. In any case, however, they have a demonstrated ability to sink or seriously damage ships and to deliver warheads with high precision against stationary land targets. Among the more troubling aspects of the missile threat is the fact that almost all such weapons may be modified to transport nuclear, chemical, or biological warheads. Since the development of guided missile systems in the 1950s, the Navy has had vigorous programs to protect itself against air threats. Shipboard antiair warfare (AAW) systems have been deployed for both ship self-defense and for area defense. The Navy developed air-to-air weapon systems to protect its tactical aircraft and to serve as an outer layer of ship defense. The AAW systems deployed by the Marine Corps have been primarily ground-based air defense systems. The relative importance of each of these systems has waxed and waned as naval missions, operational concepts, and threats evolved. In this report, current and planned naval capabilities for theater missile defense are divided into three broad categories: Antiship cruise missile defense (ASCMD), Overland cruise missile defense (OCMD), and Theater ballistic missile defense (TBMD).

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Page 14 The Navy's TBMD capabilities are further subdivided into the Navy area defense (NAD) and Navy theater wide (NTW) systems. If successful, NAD systems are designed to engage reentry vehicles (RVs) delivered by ballistic missiles after they have reentered the atmosphere. NTW systems are designed to engage threats at exo-atmospheric altitudes. This subdivision reflects the fact that the Navy is planning to use different weapon systems for endo-atmospheric and exo-atmospheric engagements. The issues mentioned in this introduction are discussed in more detail in Chapter 2, Chapter 3, and Chapter 4. Chapter 5 presents the committee's conclusions and recommendations. 1.1 CRUISE AND BALLISTIC MISSILE THREATS Through their evolving strategies Forward...From the Sea1 and Operational Maneuver From the Sea (OMFTS),2 the Navy and Marine Corps have acknowledged a shift in warfare from operations on the open seas to operations in and adjacent to littoral areas. This shift in warfare location presents many technical and operational challenges to naval forces in power projection, the most notable of which may be an increase in the land-based threat to the forces engaged in such operations. Both TBMD and cruise missile defense (CMD)—including OCMD and ASCMD—are important emerging military capabilities that will be needed if naval forces are to execute missions in and near littoral areas. Today, there are large numbers and varieties of cruise and ballistic missiles in the operational inventories of many potential future adversaries of the United States. Although high-performance ballistic missiles exist and could become available to potential future adversaries, most of the ballistic missiles that are currently available to such adversaries are of rather unsophisticated design. Many have limited accuracy of delivery and are ineffective for hitting tactical targets. As currently configured, many are nonseparating, single-stage rockets that are less stressing to defense systems than multistage missiles. Many others are not able to deploy penetration aids. In a military sense, these threats will have limited tactical value unless they carry nuclear, chemical, and/or biological warheads. However, even as currently configured, they pose a serious threat to deployed forces and assets, as well as to the political stability of neighboring or allied countries. 1 Department of the Navy. 1994. “Forward...From the Sea, Continuing the Preparation of the Naval Services for the 21st Century,” U.S. Government Printing Office, Washington, D.C., September 19. 2 Headquarters, U.S. Marine Corps. 1996. "Operational Maneuver From the Sea," U.S. Government Printing Office, Washington, D.C., January 4. Available online at <http://www.>

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Page 15 As was evident from the information presented to the committee, there are many reasons to expect that in the near future (5 to 20 years) more sophisticated variants of these ballistic missiles will proliferate. The committee observed that a number of design improvements to ballistic missiles had shown up earlier than expected, portending a significant increase in the effectiveness as well as the number of missile threats that will be faced. It anticipates that these variants will be characterized by an ability to be employed against tactical targets, an ability to deploy sophisticated penetration aids to counter defensive systems, and an ability to maneuver to evade defensive interceptors. Thus, any TBMD system that the Department of the Navy develops and fields must be considered in the context of such plausible future threats. The sophistication of cruise missiles that are currently available to potential adversaries can also stress our military forces' defensive systems seriously. Cruise missiles that can be purchased from France, Russia, and China (or indigenously manufactured) may be characterized by their low-altitude trajectories, their high velocity, their low nose-on radar cross section (RCS) values, and sensors that are robust against many forms of electronic countermeasures (ECMs). Alternatively, adversaries may elect to attack our military forces in the littorals with a large number of relatively inexpensive, low-technology cruise missiles in an attempt to overwhelm our defenses by the sheer numbers. Given these factors, the committee believes that the antiship cruise missile (ASCM) threat will intensify, especially as naval operations shift to the littorals. Defense against current state-of-the-art antiship cruise missiles (ASCMs) and overland cruise missiles (OCMs) represents a serious challenge for both existing shipboard and expeditionary warfare defensive systems and the new generation of systems now under development. 1.2 EXISTING THEATER MISSILE DEFENSE CAPABILITIES 1.2.1 Antiship Cruise Missile Defense Issues In evaluating the effectiveness of an ASCMD system, the threat cruise missile's velocity, RCS, and altitude above sea level must be considered. When these parameters are combined in a three-dimensional plot, it can be seen that there are some regions in this parameter space where the incoming missile could not be shot at and other regions where only one or two shots would be possible. The combinations of missile velocity, RCS, and altitude where current defensive systems can exercise a shoot-look-shoot (SLS) doctrine are limited. Some current threat cruise missiles are designed to operate in the regime where only one defensive interceptor launch is possible. In certain circumstances, when high-Mach-number, low-RCS, and low-trajectory cruise missiles are fired from a high-clutter land mass, it may not be feasible to launch any current defensive interceptors. Unless the Navy's currently deployed sensor systems, interceptors, and

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Page 16 weapon control systems are improved, postulated and technically realizable ASCM improvements will enable ASCMs to operate in speed, altitude, and RCS regimes where they cannot be engaged. The committee believes that the Navy has a number of important developments under way to improve its ASCMD capabilities. These include the multifunction radar (MFR), which will provide a much better X-band horizon search capability, the ship self-defense system (SSDS), which will provide non-Aegis ships with rapid response weapon control, and the evolved sea sparrow missile (ESSM), which will greatly improve engagement with advanced threats. These capabilities need to be deployed as soon as possible. 1.2.2 Overland Cruise Missile Defense Issues The current U.S. Marine Corps operational strategy, Expeditionary Maneuver Warfare 21 (EMW 21),3 envisages the use of light and highly mobile forces that are largely unencumbered by large, heavy air defense and artillery systems. The Marine Corps is looking to forces at sea to provide OCMD and fire support. Current Marine Corps concepts of operations for OCMD are based on an elevated air moving target indication (AMTI) radar with overland clutter rejection capabilities as an essential feature. The radar system that is currently available in the Navy's E-2C aircraft is inadequate for such purposes. The E-2C Radar Modernization Program (RMP) was intended to develop and deploy a suitable AMTI radar. If deployed, this radar would be the first Navy AMTI radar with significant overland detection capability. The E-2C RMP, in conjunction with the cooperative engagement capability (CEC) data link and a postulated dual-mode active/semiactive variant of the standard missile (SM)-2, would provide the Department of the Navy with an expensive (and possibly vulnerable) but respectable OCMD capability. Funding constraints are currently jeopardizing the RMP and casting doubt on the achievement of a credible OCMD capability. If funding limitations preclude the development of a sea-based AMTI capability, alternatives must be 3 Expeditionary Maneuver Warfare 21 is the Marine Corps' overarching strategy for conducting 21st century Marine Corps operations such as those described in “Operational Maneuver From the Sea”; “Ship to Objective Maneuver” (Van Riper, LtGen Paul K., USMC, 1997, “Ship to Objective Maneuver (STOM),” Marine Corps Combat Development Command, Quantico, Va., July 25, available online at <>); “Maritime Prepositioning Force 2010 and Beyond” (Krulak, Gen C.C., USMC, 1997, “Marine Prepositioning Force 2010 and Beyond,” Headquarters, U.S. Marine Corps, Washington, D.C., December 30, available online at <>); “Sustained Operations Ashore” (Krulak, Gen C.C., USMC, 1998, “The Marine Air Ground Task Force in Sustained Operations Ashore,” U.S. Marine Corps, Washington, D.C., June 10, available online at <>); and “Other Expeditionary Operations” (Warfighting Requirements Division, to be published, “Other Expeditionary Operations, Draft Concept Paper,” Marine Corps Combat Development Command, Quantico, Va.).

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Page 17 explored. The committee believes that the Navy and Marine Corps should explore alternative concepts of operations such as the coordinated use of the Air Force airborne warning and control system (AWACS) aircraft, use of the Army's joint land attack cruise missile defense elevated netted sensors (JLENS) system, the deployment of a multiple unmanned aerial vehicle (UAV) surveillance system, and/or the use of National sensors.4 Even if the RMP funding problems are resolved, projected progress in cruise missile capabilities indicates that the Navy will eventually need to provide performance beyond that of the RMP AMTI radar operating monostatically with the ADS-18 antenna. A network of distributed, multistatic sensors could provide a reliable capability to negate low-observable cruise missiles. The committee believes that the Navy should put more emphasis on advanced R&D in support of improvements to the Department of the Navy's OCMD capabilities. In keeping with its commitments to the concepts of OMFTS and Ship-to-Objective Maneuver (STOM),5 the Marine Corps has already decommissioned its Hawk6 capabilities. It has embarked on a program to develop a lightweight, mobile missile defense system utilizing an advanced medium-range air-to-air missile (AMRAAM) mounted on a high-mobility, multipurpose wheeled vehicle (HMMWV). The resulting system, called the complementary low altitude weapon system (CLAWS), should provide the Marine Corps with a limited forward-deployed air defense capability. The major problem with CLAWS is that the Marine Corps TPS-59 (V3) radar may be the only sensor (in the near term) available to provide it with target information. Although the TPS-59 (V3) is an excellent long-range air surveillance radar, it is large and difficult to transport in current amphibious shipping. Under current concepts of operations (CONOPS), the TPS-59 (V3) is unlikely to be available in the execution of OMFTS or STOM missions to support forces deployed ashore or Navy ships operating offshore. The committee believes that in such situations, the Marine Corps will need to depend on either an elevated radar with good overland performance (e.g., the E-2C RMP AMTI radar with the ADS-18 antenna) or a compact, high-performance, mobile, ground-based air surveillance radar. The committee further believes that in the years before a high-performance elevated AMTI radar—AWACS or a sea-based system—is routinely available for forward-deployed forces, the Marine Corps should rethink its concept of operations and consider placing the TPS-59 in its maritime preposition force (MPF) squadrons for a rapid response capability in support of OMFTS or STOM missions. 4 The term “National” refers to those systems, resources, and assets controlled by the U.S. government but not limited to the Department of Defense (DOD). 5 Van Riper, LtGen Paul K., USMC. 1997. “Ship-to-Objective Maneuver,” Marine Corps Combat Development Command, Quantico, Va., July 25. Available online at < http://192.156.102/stom.htm>. 6 Originally named for the predatory bird, but later the name was turned into an acronym for "homing all the way killer."

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Page 18 The Office of Naval Research (ONR), the Marine Corps, and the Army have expressed interest in the development of an air surveillance radar system called the multirole radar system (MRRS) mounted on an HMMWV. At the time this study was carried out, the MRRS was not a funded program. The committee believes that if MRRS can perform in accordance with its postulated nominal specifications, it would be suitable for the operations in which the Marine Corps envisions becoming involved. 1.2.3 Navy Area Defense and Navy Theater Wide Issues In recognition of the importance of ballistic missile defense (BMD), the Navy is developing the NAD and the NTW systems. The NAD system will employ the SM-2 Block IVA, and the NTW system will employ the SM-3. Both missiles are derivatives of the mature SM-2. Upgrades appear warranted to extend the sensitivity, discrimination capabilities, and target acquisition range of the infrared (IR) seekers proposed for the SM-2 Block IVA and the SM-3, especially to contend with future threats. Currently, the limited target acquisition range of the interceptor missile's seeker results in a very compressed end-game time line that might cause the performance of these weapons to be degraded by signature-reducing IR countermeasures such as warhead coatings or shrouds. Such countermeasures would further reduce the target acquisition range of the seekers. As currently programmed, all indications are that the NAD system is progressing through its test program successfully. The committee found the NAD system to be reasonably structured and to have manageable risks. However, it was concerned that the current system is not supported by a robust R&D program that will provide for preplanned product improvement (P3I) to allow for matching the upgrades of defensive capabilities to the upgrades of future threat ballistic missile capabilities. The committee notes that the NTW system is not as mature as the NAD system. The Achilles' heel of this program is the SPY-1 radar, which is an excellent air defense radar but a marginal radar for the full range of NTW mission requirements. As currently configured, it is not adequate to support the capabilities required of a theater-wide ballistic missile defensive interceptor. For ascent-phase engagements, which may be an important function for NTW, the large RCS of the target booster may support adequate fly-out of the interceptor; however, this engagement mode cannot be counted upon for all scenarios. In many situations, the SPY-1 will require external cueing by overhead sensors such as the space-based infrared sensor-low (SBIRS-low). Unfortunately, SBIRS-low is not progressing at a pace that can inspire confidence that it will be available in time to assume the cueing function for the NTW system. Future ballistic missiles that the NTW is likely to be called upon to negate may be sophisticated enough to launch decoys and penetration aides and to

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Page 19 maneuver. A system that is designed to perform in a robust manner against such missiles should have capabilities that are considerably more advanced than those that will be available with the Block-I NTW system as it is presently designed. Ideally, the exo-atmospheric hit-to-kill (HTK) warhead should have a multi-color IR sensor to help distinguish an incoming warhead from decoys and debris. In addition, radar that distinguishes a spinning body from a nonspinning body would be an important capability, as would laser identification and ranging (LIDAR) that permitted incoming warheads, decoys, and debris fields to be imaged. Certainly there would be other important capabilities for an HTK vehicle: greater agility, divert capability, and lethal radius that would allow it to engage tumbling but connected warheads and decoys. Should the HTK strategy prove inadequate, some thought has been given to a “kill enhancement” device to be added to the kill vehicle, but no alternatives for improved lethality are funded at present. Perhaps the greatest shortcoming of the Block-I NTW system is the lack of a high-resolution X-band adjunct to the S-band SPY-1 radar. Ultimately, a radar will be needed that will allow discrimination among warheads, decoys, and debris at ranges that support earlier interceptor engagement. Without such a discrimination capability, the defending system is required to fire a salvo at the ensemble of incoming targets rather than only at warheads. Against the small RV cross sections of the more advanced threats that exist today, there may not be any shot opportunities. The committee is concerned that no R&D programs are planned to address these issues. The plan for the Block-II phase of NTW does not appear to be completely developed. The advanced technology programs in support of NTW do not appear to be tied to requirements for improved performance or meeting advanced threats. As an example, the information presented to the committee concerning NTW technologies that are under development cited “advanced seekers” but did not say what sensitivity or resolution would be achieved or which advanced threats the improved seekers could meet. The committee recognizes that in the area of R&D to support new BMD capabilities, the Navy cannot proceed in a completely autonomous manner. R&D programs must be coordinated with and supported by the Ballistic Missile Defense Organization (BMDO). Since the Gulf War, BMDO programs have emphasized the acquisition of theater missile defense (TMD) systems and National missile defense rather than R&D. BMDO advanced technology programs have decreased in numbers and funding. As a result, the systems that are now being acquired do not have credible plans or resources for future block upgrades to correct deficiencies or meet advanced threats. Most of the technologies needed to achieve baseline capabilities against the near-term TBM threat appear to be in hand or nearly so. However, there is a dangerous lack of the technology development programs that are necessary if the Navy is to achieve the defensive capabilities that will negate plausible future threats. Forward...From the Sea and OMFTS will not be viable strategies if the

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Page 20 Department of the Navy is unable to adequately protect itself (and joint forces) against the ballistic and cruise missiles threat projected for that era. BMDO is coordinating the advanced technology program for the TMD systems programs that are being executed by the Services. Although there is certainly room for improvement in the execution of this program—for example, the committee believes that better traceability between postulated future threats and the technological responses to those threats would make better use of available resources—as previously noted, the fundamental problem faced here is inadequate resources. The committee believes that the NTW program has an extremely aggressive schedule that postpones the hard problems to future upgrades. Unfortunately, there is no attendant R&D program dedicated to the solution of these problems. As an example, the earliest versions of the NTW will have inadequate detection capabilities; moreover, no development program is in place that will eventually alleviate these inadequacies. As currently funded, the program is heavily reliant on congressional appropriations that go beyond Service requests. 1.2.4 Concepts of Operations in Combined Offensive-Defensive Environments Central to the effective utilization of these technologies are concepts for executing the missile defense missions in an operational theater. The committee sought, during several of the Navy and Marine Corps briefings, to understand the concept of operations that would be used for expeditionary operations. In particular, the committee wished to learn how the theater missile defense operations might be coordinated with other operations that take place at the same time and in the same area. Various presentations indicated that aircraft would be delivering ordnance and providing logistical support to Marine Corps units ashore. Simultaneously, ships would execute fire missions by launching extended-range guided missiles (ERGMs) and other land attack weapons as called for by the Marine Corps. The committee believes that it is necessary to formulate a concept of operations that does everything to ensure that theater missile defense can be undertaken in coordination with offensive operations. Both offensive and defensive activities must succeed without confliction or danger to friendly forces. Joint doctrine7 has been promulgated to guide the conduct of air and missile defense in a theater; however, the doctrine appears to presume that the theater 7 Fulford, LtGen C.W., Jr., USMC, Director, Joint Staff. 1999. “Joint Doctrine for Countering Air and Missile Threats,” Joint Publication 3-01, The Pentagon, Washington, D.C., October 19. Available online at <>; Ross, Lt Gen Walter K., USAF, Director, Joint Staff. 1996. “Doctrine for Joint Theater Missile Defense,” Joint Publication 3-01.5, The Pentagon, Washington, D.C., February 22. Available online at <>.

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Page 21 has already been developed and that joint forces are in place. Other than to note that the same functions must be performed in undeveloped theaters, the joint doctrine does not give guidance for expeditionary warfare. Although the doctrine is being evolved at JTAMDO8 and “early entry” operations are mentioned in the draft 2010 Operational Concept, the doctrine for offense/defense coordination is developed only to the point where the two functions are said to be synchronized. Pending the development of joint doctrine to guide initial operations in an undeveloped theater, it falls to the Navy and Marine Corps to develop the appropriate CONOPS. A CONOPS for expeditionary warfare in the littorals must address conflicting requirements for the employment of operational assets and the control of offensive and defensive operations. Concepts for conduct of the offense are amenable to preplanning to avoid conflict yet must remain flexible enough to support operations ashore by Marine Corps units whose plans may have to be changed because of real-time events. At the same time, and in the same area, defensive measures must be taken to defeat ballistic missile, cruise missile, and aircraft threats to forces afloat and ashore. The conduct of effective theater missile defense without disrupting or conflicting with offensive measures is very difficult but necessary. Several briefers9 informed the committee that concepts for coordinating offensive and defensive operations have not been worked out. Such coordination concepts deserve considerable effort, since they are critical to the conduct of expeditionary warfare and necessary for evaluating the adequacy of theater missile defense programs. 1.2.5 Battle Management Command, Control, and Communications (BMC3) Issues BMC3 must support joint as well as purely naval operations. Underlying BMC3 is the exchange of information among the missile defense sensor, command, and weapon nodes. The primary vehicle planned for this is the Link 16 networking and messaging scheme, as realized in the joint tactical information distribution system (JTIDS) radio terminals. These terminals will be installed on a variety of aircraft, surface ships, and submarines over the next several years, as well as in Patriot and theater high altitude air defense (THAAD) forces. JTIDS was first developed at least 30 years ago; thus, even though JTIDS is just now being deployed, it is very much a legacy capability. 8 Joint Theater Air and Missile Defense Organization and Ballistic Missile Defense Organization. To be published. “Annex G: GTAMD 2010 Operational Concept (Draft Version 5 (Unclassified—For Official Use Only)),” from 1999 Theater Air and Missile Defense (TAMD) Master Plan (U), The Pentagon, Washington, D.C., December 2 (Classified). 9 A listing of presentations to the committee is provided in Appendix F of this report.

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Page 22 The legacy nature of Link 16 is manifested by its lack of operational flexibility and its limited bandwidth. That is, the time division multiple-access networking scheme used by Link 16 is very complex to arrange and taxes operator skills. It can take a week or two to develop and test the scheme used in actual operation. Thus, Link 16 does not currently support flexible, rapidly conceived operations. The current maximum bandwidth of the JTIDS radio in antijam mode is 115 kbps, and it is often much less in practice—very low figures by today's information transfer standards. A more modern approach based on commercial technology would allow much greater bandwidth. Commercial wireless technology is advancing rapidly, and capacities of at least a few megabits per second are currently possible. The commercial technology appears to have the necessary quality of service for military applications, although jam resistance is not a significant factor in commercial developments. Still, the commercial technology would offer a good base upon which to build a jam-resistant capability. Several improvements are currently planned for Link 16. The joint interface control officer (JICO) position has been established to facilitate the difficult network management involved in Link 16 and the other tactical data links. Furthermore, the Space and Naval Warfare Systems Command (SPAWAR) is working to enhance Link 16 flexibility and bandwidth, among other things. These improvements have merit, and the committee supports them. However, they are best viewed as late-life upgrades to a system that is nearing the end of its technical life cycle. Link 16 passes radar track (and other) data, as do all tactical data links. The CEC, by contrast, passes, combines, and produces measurement-level data from multiple radars and other available sensors to form a composite track picture in near-real time. Low-rate initial production of CEC components began in 1998, and operational evaluation is planned for the spring of 2001. The Navy's intent is to deploy CEC widely—on cruisers and carriers and on some destroyers, amphibious ships, and surveillance aircraft—although funding difficulties may limit the realization of this objective. The composite track picture provides each CEC participant with a better track picture than that which the participant could generate alone, including higher-quality tracks and greater geographic coverage. This greater coverage will allow a given participant to launch its defensive missiles before its radar acquires a target—the so-called engage-on-remote and forward-pass concepts. Control of the defensive missiles being fired using CEC data lies in the command and decision module, which uses CEC data to control the firing of the defensive missiles. Thus, CEC does not form a complete BMC3 system nor was it intended to; loosely speaking, it is a “distributed sensor system.” The initial CEC focus is on battle group air (including cruise missile) defense. Additional uses are being considered that raise the question of whether

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Page 23 they need extensive CEC capabilities or whether lesser (and presumably less expensive) capabilities would suffice. First, CEC is being planned for use in naval and joint ballistic missile defense. However, a ballistic missile track picture is much easier to obtain than a low-altitude cruise missile picture. Second, CEC is being proposed where there is little overlap in coverage between the sensors involved—for example, coupling Aegis and Patriot in low-altitude cruise missile defense. The main benefit of CEC appears to be its ability to provide a composite track picture from overlapping sensor coverage. In both cases the question is whether exchange of track data over a (possibly modernized) tactical data link would be adequate. The committee believes a CEC capability would be valuable for battle group air defense but notes that the briefings it received did not provide analytical justification for using CEC instead of the presumably less expensive tactical data links in the cases just described. The committee cautions against use of CEC just because it is there, without adequate analysis of alternatives. Moreover, one should also be cautious about locking into CEC technology, and it must be kept in mind that it is based on an architecture first designed in the 1980s. One of the most central BMC3 capabilities—and one of the most challenging to obtain—is a complete and accurate air space picture. Such a picture is necessary, for example, to use defensive assets efficiently and to coordinate the operation of offensive and defensive forces. In realistic situations this capability is achieved today in only a small fraction of the air space. There are a number of reasons for this, both procedural and technical, including lack of a common time reference, lack of navigation capability and its integration with the tactical network, connectivity shortfalls, failure to achieve a common geodetic coordinate frame, and differences in correlation/decorrelation algorithms. In part, the problems relate to the Link-16 networking and messaging scheme, but they are much broader than that. CEC addresses some of the problems, but again they are much broader than that. To confront these problems, the Joint Requirements Oversight Council (JROC) directed in March 2000 that the Single Integrated Air Picture (SIAP) System Engineering Office be formed. The SIAP system engineer is responsible for the systems engineering necessary to develop recommendations for systems and system components that collectively enable building and maintaining a SIAP capability. Thus far, the office has identified candidate solutions to address problems such as those noted above. The near-term emphasis will be on engineering and recommending improvements to fielded systems, particularly the tactical data links. The SIAP System Engineering Office's activities thus far appear well directed. The committee believes the Navy and Marine Corps should strongly support the activities of the office and monitor those activities to make sure they are meeting naval needs. The committee further believes that the SIAP system

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Page 24 engineer should aggressively promote the development of modern alternatives that would eventually replace the current tactical data links. Obviously the Department of the Navy and the Department of Defense (DOD) cannot abandon all legacy equipment in the near term to achieve a more flexible BMC3 capability. But if they do not starting thinking soon about what that improved capability will be, they will continue to be bound to the current legacy capability.